User:Al Climbs/sandbox: Difference between revisions

Olympic Mountains
Olympic Mountains
	Mount Olympus
Highest point
Peak	Mount Olympus
Elevation	7,962 ft (2,427 m)
Geography
Country	United States
State	Washington
Parent range	Pacific Coast Ranges

Browse history interactively

← Previous edit Next edit →

Content deleted Content added

VisualWikitext

Inline

Revision as of 22:31, 2 March 2014

This is the user sandbox of Al Climbs. A user sandbox is a subpage of the user's user page. It serves as a testing spot and page development space for the user and is not an encyclopedia article. Create or edit your own sandbox here.

Other sandboxes: Main sandbox | Template sandbox

Finished writing a draft article? Are you ready to request review of it by an experienced editor for possible inclusion in Wikipedia? Submit your draft for review!

The Olympic Mountains are a mountain range on the Olympic Peninsula of western Washington in the United States. The mountains, part of the Pacific Coast Ranges, are not especially high - Mount Olympus is the highest at 7,962 ft (2,427 m); however, the eastern slopes rise out of Puget Sound and the western slopes are separated from the Pacific Ocean by the 20 to 35 km (12 to 22 mi) wide Pacific Ocean coastal plain. The western slopes are the wettest place in the 48 contiguous states. Most of the mountains are protected within the bounds of the Olympic National Park.

Physiographically, they are a section of the larger Pacific Border province, which is in turn a part of the larger Pacific Mountain System.

Geography

The range trends from the north to southeast. Canyons cut by the rivers of the wet western slopes exist in addition to those of the northeast slopes.

Location

The range runs parallel to the Pacific coast of Mexico, from just south of the Arizona-Sonora border southeast through eastern Sonora, western Chihuahua, Sinaloa, Durango, Zacatecas, Nayarit, Jalisco, Aguascalientes to Guanajuato, where it joins with the Sierra Madre del Sur and the Eje Volcánico Transversal (Transverse Volcanic Axis) of central Mexico after crossing 1,250 km (780 mi).^[1] The mountains range from 300 km (190 mi) from the Gulf of California in the north, but begin to approach within 50 km (31 mi) of the Pacific in the south.^[2] These mountains are generally considered to be part of the much larger American cordillera, the mountains extending from Alaska down to these across Western North America.^[3]

Regions

The Sierra Tarahumara or Tarahumara range is the name for the region of the Sierra Madre beginning at the Durango border and extending north. This name comes from the Tarahumara natives.^[4] This is a dramatic landscape of steep mountains formed by a high plateau that has been cut through with canyons including Copper Canyon, larger and, in places, deeper than the Grand Canyon.^[5] This plateau has an average elevation of 2,250 m (7,380 ft) with most of the more eroded canyons on the western slope, due to the higher moisture content.^[1]

The highest elevations occur in the Tarahumara range.^[6] The exact elevations of the highest peaks are not known within accurate enough ranges to determine the relative elevation of peaks. The highest point is probably Cerro Mohinora, located at 25°57′N 107°03′W / 25.950°N 107.050°W / 25.950; -107.050. Estimates for the height of the mountain start around 3,040 m (9,970 ft)^[7] and go up to 3,300 m (10,800 ft).^[8] However, Cerro Barajas, at 26°24′N 106°5′W / 26.400°N 106.083°W / 26.400; -106.083, may be as high as 3,300 m (10,800 ft)^[9] although other sources give 3,170 m (10,400 ft) as the elevation.^[10] Cerro Gordo, at 23°12′N 104°57′W / 23.200°N 104.950°W / 23.200; -104.950, may have an elevation between 3,350 m (10,990 ft)^[11] and 3,340 m (10,960 ft).^[12]

The southern end of the mountains may be referred to as the Sierra Huichola.^[13] In this area the Sierra Madre begin to give way to the basin and range province.^[14] Subranges of this area include the Sierra de Alica and the Sierra Pajaritos both in Nayarit.^[15]

Water

The mountains act as a source of water, in an otherwise arid environment from the increased precipitation from the mountain range. As such, rivers that have headwaters in the mountains to become a source of water for irrigation in the surrounding lands. From the need of water to irrigate the mountains, dams were built, which has caused several environmental concerns in the area.

As the northern end of the mountains are more arid, the Yaqui River, which drains that area is an important source of irrigation in the state of Sonora.^[16] The Yaqui drains into the Gulf of California along with the Humaya River in Sinaloa and the more southern Fuerte River.^[17] The Río Grande de Santiago drains 100000 km² from the southern slopes of the Sierra Madre.^[18] Along the more arid eastern slopes of the mountains, the Nazas River and Aguanaval River drain the mountains in a closed basin.^[19] These mountains supply 90% of the water used for irrigation within the watershed.^[20] North of this system is the Conchos River which drains into the Rio Grande.^[17]

Along many rivers the arid conditions have caused courses to be dammed to provide water for irrigation. These dams have caused concerns along with those caused by the other activities. The Yaqui has been dammed with three large reservoirs along its course.^[17] The Río Grande de Santiago has also been dammed including the Aguamilpa dam begun in 1991^[21] and the El Cajón Dam (Mexico) upstream from it.^[22] To provide irrigation water for farming the dry basin, the Nazas river was dammed in the 1930s and 40s.^[23] This has led to the former drainage lakes in the area drying up, and soil depletion from the elimination of the river as a source of soil. Due to the continued logging in the area, erosion on the slopes of hillsides has increased.^[24]

Human

Numerous small populations live in Copper Canyon, including around old missions.^[25] Many live as single families or in small settlements near fields.^[26] Creel, Chihuahua is a town with 5000 inhabitants that is a stop along the train line.^[27] South of Copper Canyon, the town of El Salto, Durango is situated along highway 40.^[28] To the west is Copala, Sinaloa.^[29]

In the South, the Cora people still live, including in the towns of Jesús María and La Mesa del Nayar.^[30] In addition, 1000 people live in the village of Huajimic in Nayarit.^[31] In Jalisco, the Bolaños River valley is populated with mining communities, such as San Martín de Bolaños, which has a population of around 3000.^[32]

Few paved roads cross the mountains, meaning that travel times can be long, even between cities that are relatively close.^[33] In the north, Mexico Federal Highway 16 connect Hermosillo, Sonora and La Junta, Chihuahua.^[34] In the mountains the La Entrada al Pacifico Corridor is an incomplete road intended to connect Los Mochis, Sinaloa and Chihuahua.^[35] Durango and Mazatlan are connected by highway 40,^[36] around 24 degrees north latitude.^[33]

Climate

The climate varies considerably between the northern and southern extents of this long mountain range. Seasonal variations also occur due to the presence of large bodies of warm water delivering warm damp air from each side of the range. This region undergoes a seasonal variety with two wet seasons, including a summer monsoon, and two dry seasons each year.

Temperature, Pressure, and Wind

Air pressure changes in Northern Mexico and the Southwest United States are the main causes of seasonal variation in the Sierra Madre. A high pressure area that rests over the mountains in the winter begins to move north of the mountains into New Mexico during the month of June.^[37] The high pressure begins to breakdown and move south during September or October; however, the breakdown is usually at a slower pace than the movement north. This high pressure belt is associated with the mechanics that form the Bermuda High.^[38]

The climate in the mountains is mild. Summer temperatures maintain a constant level. Maximum temperatures are typically in July at around 31 C^[38] with average temperatures on the order of 16 C during this same period.^[39] Mean annual temperatures are between 55–65 °F (13–18 °C) above 6,000 feet (1,800 m).^[40] Below freezing temperatures can occur in the higher mountains, with precipitation occurring as snowfall certain times of year.^[41]

During the summer monsoon, wind patterns undergo large scale changes.^[37] In May there is very little large scale wind current through the mountains, most circulates around the mountains,^[37] although onshore flow is present.^[42] As the high pressure moves north, air is pulled off the Gulf of Mexico, bringing easterly winds aloft to the mountains.^[37] On the east slope of the mountain daytime upslope winds flow to the crest, where the flow joins westerly winds.^[43] The mountains cause convection during the following monsoon season,^[42] during which nocturnal winds at low levels in the atmosphere move moisture overnight.^[43] After the high pressure breaks down, wind patterns return to those prior to the monsoon season.

Precipitation and Humidity

Precipitation varies on both annual and seasonal scales in the Sierra Madre. Annual differences in regional climate are associated with the El Niño-Southern Oscillation with El Niño years leading to a wetter climate.^[39] Monsoon rains come to the Sierra Madre in June, as the high pressure area moves north, leading to wet summer seasons. This causes east winds bringing moisture from the Gulf of Mexico. On the western side of the mountains, which are affected by the largest change in precipitation between the dry season and monsoon season,^[42] in the monsoon season rainfall can exceed 30 cm (12 in) in a single month.^[37] The southern region receives more of the rainfall than the northern.^[42] Much of this precipitation occurs as tropical storms. As the high pressure over New Mexico breaks down, rainfall in the Sierra Madre end. Because of the monsoon, the summer accounts for the majority of rainfall in the area.^[39] The spring and fall dry season separate out a weaker wet season in the winter. In addition to increasing in the southern ranges of the mountains, rainfall increases in the higher elevations of the Sierra Madre Occidental.^[39]

Humidity in the mountains varies at wide levels as does rainfall. In the early morning before dawn, the air is almost saturated (often over 90% relative humidity) near the mountain tops with low clouds over the range. Lower in the range, air is not as near saturated in the morning.^[44] Seasonal variation in humidity is also present with average May and June relative humidity around 50%, with 25% possible during the day.^[38] Also during the day, relative humidity drops and cloud levels rise as temperatures rise.^[44] The humidity of the range is also influenced by the same seasonal changes as rainfall. In the dry season dew points are low, around −22 °C in the south of the range and −24 °C to −26 °C in the north in May. In June, dew points begin to increase from the May levels up to −20 °C in the North and −16 °C in the south. By July these dew points are at −14 °C throughout the range. The range allows higher dew points throughout these periods than the surrounding low lands. This rise in humidity accompanies the monsoon.^[42]

Geology

The Sierra Madre Occidental is a high plateau of volcanic rock that is eroded in areas to reveal a basement composed of plutonic and sedimentary rocks underlying the two groups of extrusive volcanics.^[45] The lower of these groups is a series of volcanic rocks formed by lava flows. The surface of the plateau is made up of a second series of volcanic ignimbrites, covered mostly by clay rich organic soils. Some intrusions in the area have deposited ore veins that are commercially viable.

The landscape was shaped after rock placement. Rivers cut valleys into the plateau, following folds in the rocks. Rock have been broken off of the slopes, forming rocky sides. The bedrock is covered by the clay rich soils, except in eroded areas, where water carries away deposits leaving a stony surface.

Geological history

The basement is thought to be Older North American basement, especially in the North,^[46] and a number of different accreted terranes, which are mostly covered by Cenozoic Volcanism.^[47] The northern extent of the Sierra Madre is the Cortes Terrane, although the northern extreme of this contains a small portion of the Carborca Terrane.^[47] Some of the northern end may also be underlain by a Precambrian basement placed around the same time as the Grenville Orogeny.^[48] Some of this area has a series of Paleozoic sedimentary sequences from a deep marine environment underlying it, which considered by some to be part of the Cotes Terrane and by others to be transported.^[49] In some areas distinct sedimentary rocks can be identified by shallow-water Silurian and Mississippian sedimentary rocks underlying deep-water Pennsylvanian and Permian, which are divided by Mississippian rhyolite. The Permian clastics contain some detrital rock that sit alongside low-grade metamorphosed sedimentary and volcanic rocks with serpentinite.^[50]

South of the Cortes and Carborca Terranes is the San José de Garcia Terrane, which is a combination of Cretaceous arc volcanics and volcaniclastics, which may be thrusting over the Cortes terrane.^[51] The southern part of the range is made up of the Guerrero Composite Terrane, a large body, which is actually a complex of five different subterranes, although not all of these are within the main body of the Sierra Madre.^[47] However, the terrane is mostly covered by volcanics and sedimentary deposits, so it is only visible where erosion has revealed it.^[52] The main subterranes of the Guerrero Composite Terrane that are within the Sierra Madre are the Tahue and Zihuatanejo terranes.^[47] Dividing the Guerrero Terrane from the rest of the Sierra Madre terranes is a boundary that is thought to represent the Early Cretaceous Arperos Basin,^[53] a marine basin which separated the island arc that came to form the Guerrero terrane from the accretions that came to form the Sierra Madre terrane.^[54] It contains a lower formation made up of pillow_basalts with pillow breccias, tuffs, and shales underlying a group of pelagic limestones, oozes, and turbidites.^[54]

Covering the southern basement are sedimentary and metamorphised sedimentary rocks containing argillite, limestone,^[55] volcanic schist, slate, and greywacke which were exposed in the canyon of the Santiago River.^[49] Near these sediments late Oligocene to early Miocene granite and granodiorite intrusive bodies occur. A possible cause of this is that these bodies were roof pendants which were uplifted by plutons.^[55] Mesozoic limestone also occurs in northern portion of the mountains, mostly from the Cretaceous.^[33]

Towards the end of the Cretaceous, the Laramide orogeny increased the activity of magmatism in the area, forming the first major igneous series in the area.^[56] The igneous series are made up of formations of plutonic and volcanic rock, which would later be exposed. Interbedded with these rocks are sedimentary deposit rocks. In the center of the range, some of these rock have been deformed by tectonic forcing that occurred at the same time. The southern part of the range contains none of the volcanism that is apparent in the northern range. These formations ended in the Paleocene.^[49] Eocene volcanism formed a series of andesitic and rhyolitic formations in the area, with spatial and temporal variations throughout. Most of the gold and silver deposits are also in these rocks.^[57]

In the Oligocene ash flows became the predominate deposit of the area, with interbedded lava flows between. These ash flows began the second series of high magmatism formations. The ignimbrite flare up formed a series of ignimbrite formations layered one atop another,^[56] that are sometimes broken by lava flows.^[46] The ignimbrite formations in this area cover the largest area of any known series, with ten calderas identified in the province.^[58] Three of these calderas are placed in Copper Canyon. The lava has formed a series of mafic rock that form the Southern Cordilleran Basaltic Andesite Suite.^[59] The tuffs are above a thick formation of lava rock. Around five or six units have been identified, mostly around the Copper Canyon area. These tuffs have actually allowed wide ranging correlation with formations in other geographical areas, for example Death Valley.^[60]

During the Miocene three periods of volcanism marked separate events in the Sierras. Each Period is marked by different volcanic processes.^[61] The first was a continuation of the Oligocene flare up, which lasted through the early Miocene. This may be a distinct second occurrence of the same process, placing slica rich lava above Oligocene rocks.^[49] Also in the early Miocene more intermediate Basaltic andesites occur along faults and in grabens.^[61] Beginning in the early Miocene and continuing into the middle, an arc of andesite was placed during the spreading of the Gulf of California.^[55] The basin and range style faulting of the middle-late Miocene took place at the same time as the placement of alkali basalts,^[57] In the westernmost slopes mafic dikes formed. These events have also been linked to the subduction of the Farallon Plate.^[62] Episodes of volcanism continued into the Quaternary.^[57]

Structures

The Sierras are believed to be a thick core covered by volcanics and eroded by numerous rivers. Some have suggested that the basement of the mountains have numerous intrusions made by mafic magma.^[49] The mountains are made up at the surface of large scale ignimbrite sheet which have been incised by rivers flowing from rainfall in the mountains.^[63]^[64] The surface of the plateau is almost exclusively from the second series of flows causing the rock that is most visible to be ignimbrites with lava flow layers.^[57] The region has a general strike from just west of north to just south of east.^[64]

Faults in the area tend to be younger than the upper volcanics, excluding those associated with calderas,^[57] but do occur in distinct periods.^[46] The large faults along the eastern slope^[57] have caused the slope to be made up of large escarpments that face into the interior basins.^[64] These faults are commonly covered by alluvium and basalt, making them difficult to discern, but can be found in certain fault blocks.^[57]

Grabens have formed in the north, and some of these are filled with volcanic and sedimentary floors,^[55] and long depressions have formed in the southern Sierra Madre.^[65] The faulting decreases in the center of the range where the faults are mostly small normal faults, but increases once again on the western slope.^[57] In fact, the major normal faults tend to diverge around the center of the core and join at either end.^[46] Some of these faults may have allowed ignimbrites to erupt from the surface, and so there may be some association between the ignimbrite occurrence and faults;^[65] this can be used to find out information about different kinds of basement rock present.^[49]

There are two faults dividing the Sierra Madre from the central Mexican Plateau. The more southern one is the north–south Aguascalientes fault extending 150 kilometres (93 mi) from Altos de Jalisco to near Zacatecas, where it joins the more northern northwest–southeast trending San Luis–Tepehuanes fault extending from Guanajuato to Durango.^[66] The southern boundary of the Sierra Madre Occidental with the Jalisco block is a series of folds, thrust, and left lateral faults date from the middle Miocene. This may be evidence for a left transpressional shear zone.^[49] The area between this boundary and the Aguascalientes fault is filled with numerous grabens and half-grabens, as well an east west left shear zone, the El Roble shear zone. At the west end of these grabens and half-grabens are the Pochotitan and the more northerly San Pedro fault systems, which form the western boundary of the faults in the southern mountains.^[62] In the north there is an unknown boundary between the Cortes Terrane and the Guerrero Composite Terrane. Some theorize that this is a section of the Mojave–Sonora Megashear, but this theory is not universally accepted; however, the Megashear is important, and, in fact, is necessary for reconstructions of the opening of the Gulf of California, as of 2003.^[67]

Mineral deposits

On a smaller scale, mineral deposits are distributed in formations of the Sierra Madre, although the events that placed these deposits vary throughout the mountains. The Guerrero composite terrane contains many of the economic deposits, often found in ore bodies younger than the Cretaceous.^[52]

Gold and silver deposits most commonly occur in the altered andesites of the early volcanics,^[57] typically these deposits are between 30 and 50 million years old.^[68] These are believed to be caused by later intrusions into the early flows. Fissure-vein deposits have been divided into two groups of fissure vein deposits, which are divided geographically into an eastern and western series.^[68] In the east, the gold and silver are accompanied by lead and zinc. In the south, the Bolaños mine district is contained with the Bolaños Graben.^[69] Some also occur as epithermal deposits. Also, some gold occurs along with copper in Cenozoic iron-oxide skarn and replacement deposits along the Pacific.^[52]

In addition to gold and silver and their related deposits, tin, iron, and mercury occur, sometimes in later units,^[68] mostly in later volcanics, and Molybdenum occurs in the mountains, often along with older copper deposits^[57] or in oligocene deposits in the east.^[68] The belt of tin deposits resides mostly within the eastern slopes from Durango to Guanajuato.^[68] In these areas, tin occurs in rhyolitic ignimbrites in many, possibly over 1000,^[70] small deposits^[57] of cassiterite. Typically these deposits are divided from overlying ignimbrites by breccia, which may also contain ore. Many of these are thought to be hydrothermal deposits^[70] To the east of these units is a belt of more mercury deposits, followed by another belt of manganese deposits, although these deposits are mostly limited to Chihuahua and Hidalgo.^[68] Iron occurs in three different regions placed by different mechanisms. Along the Pacific there the numerous skarn and replacement deposits mentioned above with relation to gold.^[68] Iron occurs in Durango in the form of magnetite lava flows, which are often surrounded by smaller hematite deposits, thought to be ash flows.^[57] There is also a belt of iron deposits further east.^[68]

Soil

Most soil in the mountains is covered by an organic rich layer over layers rich in clay.^[71] Soils are commonly phaeozems that are up to 100 centimetres (39 in).^[71] Some soils are cambisols that are less than 2 metres (6.6 ft) deep and well drained.^[20] Due to the high clay contents, which block water from being absorbed into the soil, larger rock particles in the soil help reduce runoff and soil losses from erosion. Areas that are covered in stone are known as lithosols and make up most of the remaining surface in the mountains,^[71] especially on upper slopes.^[20] The last major soil type are vertisols which are thin mineral poor soils. Soils at higher elevations experience more leaching, due to increased rainfall.^[72] Acidic soils may have lower calcium content, leading to lower plant soil quality. Soils along the eastern slopes have increased organic content and a clay heavy layer that is developed more than those of the more arid eastern lands.^[64] The thickness of soil layers also increases.

Problems with soil degradation have been aggravated by the cultivation of drug crops, leading to deforestation of many areas.^[73] Other problems include overgrazing, which has led to terracing from cattle paths and the formation of a soil crust, and soil acidification, which poses a risk to some grasslands as of 2002.^[20]

Ecology

The mountains support a variety of different ecosystems, varying by elevation and relative east-west location, which influences the local climate, primarily precipitation.

Flora

Olympic forests are coniferous forests, unique among mesic temerpate forests in their almost complete dominance by conifers rather than by hardwoods.^[74] The hardwood:conifer timber volume ratio is 1:1,000 in the maritime Pacific Northwest. Another unique feature of Olympic forests is the size and longevity of the dominant tree species. Every coniferous genus represented here is represented by its largest and longest-lived species, and some of its second and third ranked species as well.^[74] Biomass accumulations are among the highest in the temperate forest zones. Dominance of conifers is thought to be a result of the amount and timing of precipitation.^[74] The dry summers limit the growth of deciduous trees, such as most hardwoods. Evergreens, such as most conifers, are able to take advantage of the winter precipitation by continuing to photosynthesize through fall, winter and early spring, when deciduous trees are not able to photosynthesize. No deciduous conifers occur in the Olympics; larch trees occur in the much-drier eastern Cascades, but not in the Olympics or western Cascades. There is only one species of evergreen hardwood, the madrone.^[75] The great size and age of conifers here is thought to be a result of the relative lack of frequent windstorms compared to Asian cyclones and typhoons, or eastern American hurricanes.^[74]

Along the western flanks of the mountains the increased orographic precipitation supports temperate rain forests in the Quinault, Queets, Hoh, and Bogachiel river valleys at low elevations.^[76] Protection by Olympic National Park, has allowed these rain forests to retain old growth trees, which supports a varied ecosystem.^[77] The Olympic rain forests are composed primarily of Sitka Spruce and Western Hemlock, as are the surrounding lowland Sitka Spruce forests, but are distinct in having a relative abundance of groves of Bigleaf maple and Vine maple, which support large epiphytic communities of mosses, lichens, ferns, and clubmosses; an abundance of nurse logs on the forest floor; a relatively open forest canopy and sparse shrub layer; and a dense moss layer on the forest floor. The rain forests are the wintering grounds for herds of Roosevelt elk and it is thought that browsing by the elk is responsible for the open shrub layer and the dominance of Sitka spruce over Western hemlock.^[74]

The rain forests are just one type of forest found in the Olympic Mountains. Franklin and Dyrness ^[74] set out 5 forest zones: Sitka spruce, Western hemlock, Silver fir, Mountain hemlock, and Subalpine parkland. Other authors include a sixth, Douglas-fir zone.^[78] Different plant associations are typical of one or more forest zones. For instance, the rain forest plant association described above is a member of the Sitka spruce forest zone.

The Sitka spruce zone is a lowland zone dominated by Sitka spruce and Western hemlock. Precipitation is high, winters are mild, elevations are low. This forest zone is typically found at very low elevations on the western coastal plain and not in mountainous areas, although it can be found as high as 1,900 feet (580 m).^[74]^[79]

The lower elevations of the Olympic mountains, from roughly 480 feet (150 m) up to 1,800 feet (550 m) - 3,700 feet (1,100 m), feature the Western hemlock zone, so-called because in most of the zone, the climax tree species would be Western hemlock, even though much of the area is dominated by Douglas-fir.^[74] The reason for this is that Douglas-fir is an early seral species, and reproduces primarily after disturbances such as fire, logging, landslides, and windstorms. Western hemlock does not reproduce well on disturbed, exposed soil but germinates under the canopy of Douglas-fir, eventually overtaking the forest by shading out the Douglas-fir, which cannot reproduce in shade. In this zone, despite the high annual precipitation, drought stress in summer is sufficiently severe to limit growth of many species, such as Sitka spruce. Hardwoods such as Bigleaf maple, willows, and Red alder are limited to disturbed sites and riparian areas. Red-cedar grows in the wettest sites.^[74] A very small area of the northeastern rain shadow contains the limited Douglas-fir zone, where it is too dry for Western hemlock.^[78]

Moving up in elevation and moisture availability is the Silver fir zone, up to about 3,900 feet (1,200 m). This zone gets more precipitation, and more of it as snow, than the lower, warmer, drier Western hemlock zone.^[74] The cold and the snowpack combine to limit growth of lower-elevation plants. On the other hand, Silver fir is less drought tolerant and less fire tolerant than either Douglas-fir or Western hemlock. Slide alder (Alnus viridis sinuata) grows in snow-creep areas and avalanche chutes, along with Yellow-cedar. Meadows of Thimbleberry also grow in this zone, often intergrading between the Slide alder chutes and the Silver fir forest.^[74]

The next higher forest zone is the Mountain hemlock zone, the highest forest zone in the Olympic mountains.^[74] In this zone most precipitation falls as snow and the snow-free growing season is very short. In the drier rainshadow side of the mountains, Mountain hemlock is largely replaced by Subalpine fir. At the higher elevations of the Mountain hemlock/Subalpine fir zone, tree cover is reduced to isolated stands of trees called tree islands, surrounded by subalpine meadows, in the Subalpine Parkland zone. Variations in substrate, topography, moisture, and snowpack depth and duration determine the vegetation community. Tree islands form on convex topography, which tends to gather less snow and shed it sooner than surrounding level or concave topography.^[74]

In the West, the subalpine zone is dominated by mountain hemlock.^[77] It occurs along with subalpine fir from 1,100 to 1,650 metres (3,610 to 5,410 ft) in the Bailey Range; however, the range of this forest type is not extensive and does not extend much west of Mount Olympus, nor is it common in the East. Chamaecyparis nootkatensis|Yellow-cedar is sometimes found in relation to these plants.^[80] In the East and other drier areas, the subalpine zone is dominated by Subalpine fir.^[77] It can occur with other trees, including Mountain hemlock, Silver fir, and Yellow-cedar, but what characterizes these zones is the dominance of Subalpine fir. These forests occur on the eastern ridges from 1,300 to 1,800 metres (4,300 to 5,900 ft).^[80]

In the Olympics, the treeline is between 5,000 feet (1,500 m) and 6,000 feet (1,800 m)^[81] but can be as low as under 4,000 feet (1,200 m) in some places.^[82] Treeline is a function of both elevation and precipitation, particularly the amount of snow that falls each winter.^[75] The growing season for trees is relatively short in the higher elevations of the windward Olympics, compared to similar elevations in other mountain ranges, due to the large accumulations of snow that take a long time to melt each year.

Subalpine meadows in the Olympic mountains are of 5 types. Heath shrub meadows are dominated by ericaceous huckleberries and heathers. Lush herbaceous meadows are typified by Sitka valerian and Showy sedge. Drier areas or those with longer snow cover grow dwarf sedge (Carex nigricans) or grass (Festuca viridis) meadows. Phlox diffusa typifies the low herbaceous meadows of pumice, talus and scree slopes and other rocky areas.^[74] American saw-wort is common in both mountain meadows and lower subalpine parklands in the Olympics.^[74]

Above timberline is the Alpine zone, not a forest zone since no trees can grow this high. The alpine zone in the Olympics is much more limited in size than in other temperate mountain ranges, from 1,800 metres (5,900 ft) to 2,250 metres (7,380 ft).^[74] The high precipitation of the Olympics creates permanent snow and ice at lower elevations than is typical for other mountain ranges, cutting off the alpine vegetation zone. Most of the alpine vegetation is on the rain shadow side, in the northeastern Olympics, where there is less permanent snow and ice. Alpine vegetation is low herbaceous, typified by Phlox diffusa and species of Carex. Many of the Olympic Mountain’s endemic plants occur here, such as Piper’s bellflower (Campanula piperi) and Flett’s violet (Viola flettii).^[75]

Endemic Plants

Olympic Mountain milkvetch Astragalus australis var. olympicus
Piper's bellflower Campanula piperi
Spotted coralroot Corallorhiza maculata var. ozettensis
Flett's fleabane Erigeron flettii
Thompson's wandering fleabane Erigeron peregrinus ssp. peregrinus var. thompsonii
Quinault fawn lily Erythronium quinaultensis
Olympic rockmat Petrophylum hendersonii
Olympic Mountain groundsel Senecio neowebsteri
Olympic cut-leaf synthyris Synthyris pinnatifida var. lanuginosa
Olympic Mountain dandelion Taraxacum olympicum
Flett's violet Viola flettii^[75]

Fauna

Mammals extirpated from the Olympic Mountains are the Fisher Martes pennanti and the Gray Wolf Canis lupus. The Fisher was declared extirpated from Washington State when no Fishers were detected during state-wide carnivore surveys in the 1990s and 2000s. A reintroduction project was initiated in 2007, in partnership with Olympic National Park.^[83] The Gray Wolf was extirpated from Washington State in the early 20th Century. The last wolf documented in the Olympics was trapped in 1920.^[75] In the early 21st Century, wolves are naturally migrating back into eastern and north-central Washington State, but there is no evidence of wolf migration into the Olympics and no plan to translocate wolves to the Olympics.^[84]

The Gray Wolf is listed as Endangered by the US Fish and Wildlife Service ^[84] and the Fisher is listed as State Endangered by the Washington Fish and Wildlife Commission.^[83]

Previous to the extirpation of the Gray Wolf, Coyotes (Canis latrans) occurred in the lowlands of the Olympic peninsula but not in the mountains.^[75] With the absence of wolves, coyotes have been moving up into the higher elevations of the mountains and may be responsible for population declines in the Olympic marmot.

The Mountain Goat Oreamnos americanus is not native to the Olympic Mountains but was introduced for hunting in the 1920s^[85] by a coalition of the Forest Service, the Clallam County Game Warden, and the State Game Commission.^[86] Mountain Goats in the Olympics have been associated with damage to alpine vegetation and soil erosion,^[75] and have shown aggression towards people. In 1999, a Mountain Goat gored a hiker at the summit of Mt. Ellinor in Olympic National Forest, and in 2010, a Mountain Goat fatally gored a hiker on the Klahane Ridge trail in Olympic National Park.^[87] In 2012, the trail to Mt. Ellinor was closed in summer due to aggressive goats, re-opening in the fall.^[88]

Roosevelt elk Cervus canadensis roosevelti range along the Pacific coast from the Russian River to Vancouver Island.^[75] Olympic and Vancouver Island elk are some of the last pure Roosevelt elk herds left; those in the Cascades have mixed with Rocky Mountain elk. Olympic National Park has the largest population of Roosevelt elk in the world. Some herds spend winter in lowland valleys, summer in high country, in subalpine meadows. Other herds live year round in lowland forests and meadows. Elk prefer more humid areas, the Sitka Spruce, wet Western Hemlock, and Mountain Hemlock zones.^[78] Elk browsing is believed to be responsible for the open park-like structure of the Olympic rainforests; the elk graze on hemlock and shrubs, leaving the Sitka spruce to grow. Elk browsing also increases diversity of grasses and forbs. Elk exclosure experiments in rainforest valleys show more species of vegetation growing outside the exclosures, where elk browse, than inside; while there are more brush and saplings inside exclosures, there are more grasses and forbs outside.^[75] Elk browsing improves forage for other herbivores like deer, voles and snowshoe hares. Elk prefer old growth forest and young alder groves over the large, even-aged plantations common on commercial timber land, although they will use small, recent clearcuts where they mimic natural forest openings.^[75]

Both the Press and O’Neil expeditions were impressed by the quantity and tameness of the elk.^[89]^[90] Both expedition leaders prohibited shooting the elk and deer except when the expedition was in need of meat. The Olympic National Monument was formed to protect the elk after the herds were reduced to less than 2000 animals. The population rebounded, and in 1937 a hunting season for elk was opened in the Hoh River valley. 2000^[86] to 4000^[75] hunters came, several times as many as expected.^[86] One hunter was accidentally shot and died. A second hunter drowned in the Hoh River. A pack horse was shot. The Hoh River flooded, stranding hunters and washing away their camps. Forest Service and State Game personnel were overwhelmed with rescue efforts (lost, stranded, or injured hunters) and dispute resolution. Over 800 elk were killed, some left lying in the forest.^[75] Proponents of a National Park used the 1937 elk hunt as an argument in favor of permanent protection for Olympic’s elk herds. Not all the elk herds are protected inside the National Park. Some migrate in and out of the Park, and others live entirely outside the Park; these are subject to regulated hunting when not in the National Park.

Blacktail deer Odocoileus hemionus columbianus prefer drier areas than elk, such as the dry Western Hemlock, Douglas-fir, and Subalpine fir zones.^[78] Similar to the elk, blacktail deer winter in lowlands, or along south-facing ridges, and summer in the high country meadows.^[82]

American black bear Ursus americanus are numerous in the Olympics.^[82] Olympic bears eat salmon, rodents, huckleberries, tree bark, insects, and deer or elk carcasses.

Cougar Felis concolor is the largest carnivore in the Olympics. Their main prey are deer and elk but they also hunt porcupines and insects. They are rarely seen in the Olympics but are thought to be widespread and relatively common.^[82]^[75]

Mountain beaver Aplodontia rufa is a large primitive rodent endemic to the Pacific Northwest. They are common in the Olympics, preferring wet scrubby thickets and second growth timber.^[82]

Banana slug Ariolimax columbianus is another Pacific Northwest endemic. Slugs are abundant in the Olympic forests, outweighing mammals and birds combined.^[79] They thrive in the cool damp shade of the forests. The banana slug is the largest and most conspicuous of Olympic slugs.

Northern spotted owl Strix occidentalis caurina is an old-growth dependent species and is listed as Threatened under the Endangered Species Act. The majority of spotted owls on the Olympic peninsula, along with the largest preserve of temperate old-growth forest, live in the National Park.^[75] Spotted owls prey on flying squirrels and snowshoe hares, and are themselves preyed on by great horned owls Bubo virginianus. The density of the canopy of an old-growth forest gives the spotted owls some protection from the larger, less agile great horned owls.

Rufous hummingbird Selasphorus rufus is the only hummingbird in the Olympics. They overwinter in Mexico and southern California, arriving in the Olympics in February or March with the flowering of the Indian plum Oemleria cerasifera.

Harlequin duck Histrionicus histrionicus breeds in fast-moving mountain streams in the Olympics. They spend the rest of the year in coastal waters.^[82]

Osprey Pandion haliaetus and bald eagle Haliaeetus leucocephalus fish in Olympic rivers, nesting in large old trees. Both are relatively common, the bald eagle more so along the coast than in the mountains.^[82]

Olympic rivers are dominated by Pacific salmonids, the Oncorhynchus.^[82] Chinook, coho, pink, rainbow and steelhead, and cutthroat all spawn in Olympic rivers. Chum and sockeye also live in coastal Olympic peninsula rivers but do not reach into the mountains. Bull trout Salvelinus confluentus and Dolly Varden trout S. malma also live in Olympic rivers.^[82]^[75]

Endemic fauna

There are at least 16 endemic animal species.^[91]

Mammals

Olympic marmot Marmota olympus
Olympic chipmunk Tamius amoenus caurinus
Olympic snow mole Scapanus townsendii olympicus
Mazama pocket gopher Thomomys mazama melanops
Olympic ermine Mustela erminea olympica

Amphibians

Olympic torrent salamander Rhyacotriton olympicus

Fish

Olympic mudminnow Novumbra hubbsi
Beardslee rainbow trout Oncorhynchus mykiss irideus
Crescenti cutthroat trout Oncorhynchus clarki clarki

Insects

Hulbert's Skipper butterfly Hesperia comma hulbirti
Olympic grasshopper Nisquallia olympica
Mann's gazelle beetle Nebria dammanni
Quileute gazelle beetle Nebria acuta quileute
Tiger beetle Cicindela bellissima frechini

Molluscs

Arionid slug Hemphillia dromedarius
Arionid jumping slug Hemphillia burringtoni^[75]

Near-endemics, those that occur in the Olympics as well as other parts of a limited range, include the Cope's Giant Salamander (Dicamptodon copei), and the Van Dyke's Salamander (Plethodon vandykei,) both found primarily in the Olympics and other mountainous areas of western Washington; the Tailed Frog (Ascaphus truei), of Pacific Northwest mountain streams, and the Mountain Beaver (Aplodontia rufa) of the coastal Pacific Northwest.^[75]

History

Prehistory

For the original inhabitants of the Olympic Peninsula, the highest peaks of the mountains were the only refuges during the Great Floods at the beginning of time.^[92] For the Elwha Klallam people, that peak was Mount Carrie; for the Skokomish, it was a peak west of Mt. Ellinor. The Thunderbird figure of the Hoh tribe lived on Mt. Olympus, in a den under Blue Glacier. People in the Skokomish, Quinault, and Elwha watersheds regularly traveled into the high country to hunt elk, gather huckleberries and beargrass, and perform spirit quests. Trails across the mountains allowed members of the various tribes to visit and trade with each other.^[75]^[92] The cross-Olympic expeditions of the 1890s found tree blazes that they took to mark Indian trails.^[89]^[90]

Archeological evidence shows that the Olympic Mountains were inhabited by Paleolithic hunters after the retreat of the Cordilleran Ice Sheet.^[75] Stone tools in the Deer Park area date to 7600 years ago, prior to the volcanic eruption of Mount Mazama. Similar tools have been found near Lake Cushman and throughout the Olympic subalpine meadows and ridges, as well as in coastal areas. In addition, a fragment of a woven basket found in the Olympic subalpine of Obstruction Point was radiocarbon dated to nearly 3000 years ago.^[75]^[92]

The mountains were originally called "Sun-a-do" by the Duwamish Indians,^[93] while the first European to see them, the Spanish navigator Juan Perez, named Mount Olympus "Santa Rosalia", in 1774.^[94] But the English captain John Meares, seeing them in 1788, thought them beautiful enough for the gods to dwell there, and named the highest point "Mount Olympus" after the mountain in Greece. Various names for the mountains were used based on the name Mount Olympus, including the Olympic Range, the Olympian Mountains, and the Olympus Range.^[93] Alternate proposals never caught on, and in 1864 the Seattle Weekly Gazette persuaded the government to make the present-day name official,^[95] although other names continued to be used.^[93]

First O'Neil Expedition, 1885

Though readily visible from many parts of western Washington, especially Seattle, the interior was almost entirely unexplored until 1885, when 2nd Lt. Joseph P. O'Neil of the 14th Infantry, stationed at Fort Vancouver, led a small expedition into the northern Olympics from Port Angeles.^[90] O’Neil led an expedition of 3 enlisted men, 2 civilian engineers, and 8 mules out of Port Angeles in July 1885. The expedition cut a mule trail from Port Angeles up to Hurricane Ridge and camped near the current site of the National Park visitor center. From there, they explored and built trail to the east and south, exploring the upper Dungeness and Dosewallips River watersheds, and to Cameron Basin near Mt. Anderson. O’Neil was recalled by the Army in August to be transferred to Fort Leavenworth in Kansas, and the expedition had to return to Fort Townsend. The Obstruction Peak Road and portions of the Hurricane Ridge Road and the Klahane Ridge, Grand Pass and Lost Pass trails in Olympic National Park originated with the mule trails built by this expedition.^[96]^[90]

In late 1889, Charles A. Gilman and his son Samuel explored the East Fork Quinault up to its headwaters, but chose to return the way they came rather than cross over the mountains.^[90]

Press Expedition 1889-90

The first crossing of the Olympic Mountains was done from November 1889 through May 1890 by the Press Expedition, a group of 5 men lead by Canadian James H. Christie, sponsored by the Seattle newspaper Press, which ascended the Elwha River and descended the North Fork Quinault River. The Press party included 2 mules, which both died in separate incidents, and 4 dogs, 1 of which was killed by an elk.^[89] The Press Expedition crossed in winter, in order to beat O'Neil's planned expedition for the summer of 1890. Initially the expedition built a boat on the Elwha to tow their cargo upriver, but the icy water and deep snow covering boulders and fallen trees made this mode of transportation very slow – after 2 weeks, the men had towed the boat 4 miles (6.4 km). It did, however, carry cargo where the mules could not. Christie and his men abandoned the boat and switched to the mules when they reached the head of navigation on the Elwha, but the mules both died in separate incidents fairly early in the expedition. Deep snow, steep slopes, and fallen trees made travel extremely difficult for the mules, along with lack of forage.^[89]

The expedition carried minimal food, expecting to find game.^[89] In the lowlands, game and fish were plentiful, but the heavy snow that winter drove game out of the mountains and for long stretches in the high mountains, the men were reduced to eating ‘flour soup’. Unlike O’Neil’s military expeditions, the Press Expedition had no resupply line. Once into the high mountains and the deep snow, with no game, they went weeks with no meat and little to eat besides flour and beans. The men carried all the cargo on their own backs through one of the roughest and most labyrinthine sections of the high mountains, through snow 10 to 15 feet (3.0 to 4.6 m) deep. On climbing a peak to get a view of the area, Christie estimated the snow at the peak to be 25 feet (7.6 m) deep. Avalanches occurred on a daily basis. Crossing Low Divide between the upper Elwha and the headwaters of the North Fork Quinault, the men climbed a vertical cliff, requiring Christie to climb to a ledge and then lower a rope to the men below. Packs, dogs, and men were hauled up the cliff by rope. Once on the Quinault side of the divide, the men shot and ate a bear, the first meat they had had for several weeks of strenuous winter mountain travel.^[89]

Deep snow prevented proper trail building for much of their route, although they did cut a rough trail along the lower reach of the Elwha River, and blazed trees along their route.^[89] They used elk trails wherever possible, and walked in the river when there was no other way through due to steep terrain or dense brush. It took the expedition four months of slogging through dense brush and windthrows, swamps, steep canyons and deep, wet, slushy snow just to reach the inner mountains. Once in the high mountains, the relief was so precipitous that the men estimated they traveled up and down as much as 6 miles (9.7 km) to cover 2 miles (3.2 km) horizontal miles.^[89]

Once on the mainstem Quinault River, the men built a raft, but it wrecked on a logjam.^[89] The men saved the dogs and the one pack that contained their maps, photographs, and records made along the route, but lost all their food, armaments, utensils, fishing tackle, shelter, and the few mineral and plant specimens and animal skins they had collected; and the men were split on opposite sides of the river, unable to reach each other. They continued walking down the river, eating salmonberry shoots and spruce bark, until a settler and a Quinault Indian guide canoeing to Lake Quinault rescued them.^[89] When the O’Neil expedition of 1890 reached the mainstem Quinault River a few months later, they found some of the items the Press Expedition had lost in the wreck.^[90] The settler and neighboring Indians took the expedition across Lake Quinault and down the lower river to the coast in mid May, nearly six months after they left Port Angeles.^[89] From the mouth of the Quinault they traveled to Aberdeen and then to Seattle. Their account of their expedition, along with photographs and a full-page map, was printed in a special edition of the Press on July 16, 1890. The Elwha River and North Fork Quinault trails in Olympic National Park follow the route of the Press Expedition, with a detour through the highest mountains and around the vertical cliff at Low Divide.^[96]

Second O'Neil Expedition, 1890

O'Neil returned to Washington in 1887 and started planning another expedition.^[90] The Olympic Exploring Expedition, led by O’Neil, crossed the southern Olympics in the summer of 1890, ascending the North Fork Skokomish River and descending the East Fork Quinault River, building a mule trail the entire distance.^[90] This expedition was larger than the 1885 expedition, and would be resupplied by mule train from Hoodsport on Hood Canal, allowing time for scientific exploration of the area. The expedition consisted of 10 soldiers, 1 civilian mule packer, 4 civilian scientists from the Oregon Alpine Club, 11 mules, 1 bell mare to lead the mule train, and up to 4 dogs. The scientists collected specimens of plants, animals, and minerals, which they shipped back to Portland by way of the mule train to Hoodsport. The majority of the party was assigned to cutting the mule trail, while 2 or 3 man exploring parties fanned out and scouts went ahead. The scouts and side exploring parties scrambled up slopes on all fours, pulling themselves up by grabbing onto vegetation; descended similar slopes by sliding, deliberately or inadvertently; hacked and crawled through dense brush and windthrow; waded up rivers and streams when there was no other way through; felled trees to bridge ravines and rivers; and traversed narrow ridges of crumbling vertically-oriented shale. Hornet and yellow jacket wasp attacks were a daily occurrence, sending men scrambling and mules stampeding, one over a cliff to her death. Where the men crossed swamps, devils club thorns impaled the men and broke off in their skin, creating painful inflammations.^[90]

Once camped in the central mountains, O’Neil sent out small exploring parties to the Duckabush, Dosewallips, South Fork Skokomish, Wynoochee and Humptulips rivers, and to Mount Olympus and the Queets River. One party of 3 men climbed what they thought was Mount Olympus but was in reality one of the neighboring peaks, Athena II. A fourth member of the summit party became separated on the climb and ended up descending the Queets River alone, and was taken in by a Quinault Indian family. They were reluctant to believe that he had crossed the Olympics, not believing it was possible to do so; but they accepted his story when he was able to point out reference points on a map. (Many members of this expedition spoke Chinook jargon.) From their settlement, he was able to rejoin the expedition in Hoquiam. O'Neil's reports on his explorations resulted in his recommendation that the region be declared a national park.^[90]^[97]

20th Century

Mount Olympus itself was not ascended until 1907, one of the first successes of The Mountaineers, which had been organized in Seattle just a few years earlier.^[98] A number of the more obscure and least-accessible peaks in the range were not ascended until the 1970s.

President Grover Cleveland protected the forests of the Olympic Peninsula with the Olympic Forest Reserve in 1897.^[97] Initially the Reserve consisted of over 2 million acres, nearly the entire peninsula.^[75] Forest Service surveyors Dodwell and Rixon spent three years surveying, timber cruising, and mapping the new reserve. Their report, published in 1902, reported that most of the land was not suited to agriculture, but local politicians had already convinced President William McKinley to remove the most valuable lowland timber from the reserve, claiming it should be open to homesteading. Private timber companies paid ‘homesteaders’ to file claims on land that they then sold to the timber company.^[75] At the same time, commercial hunters reduced the Olympic elk herds to fewer than 2000 animals, prompting the state legislature to impose a temporary moratorium on elk hunting in the Olympics. The Forest Reserve was reorganized under Gifford Pinchot as the Olympic National Forest in 1905, with an emphasis on commercial utilization of timber and minerals and fire protection, as well as hunting and trapping.^[86] With the passing of the Antiquities Act in 1906, which allowed the president to designate national monuments, Mount Olympus National Monument, administered by the Forest Service, was proclaimed by Theodore Roosevelt in 1909 in order to protect the elk herds. In 1914, the new supervisor of the Forest Service, Henry Graves, made a trip to the Olympics to determine if commercial timber and minerals were being tied up in the National Monument.^[86] As a result of Grave’s report, President Woodrow Wilson removed a third of a million acres from the Monument.

The Elwha River was dammed in 1910 with construction of the Elwha Dam.^[99] A second dam was built a few miles upstream in 1927. Neither dam had any fish passage for the salmonid runs, completely eliminating salmonids from over 70 miles of river.^[100] Congress authorized removal of these dams in 1992, and work began in 2011.^[101]

The North Fork Skokomish River was dammed in the 1920s by the city of Tacoma, enlarging the original Lake Cushman by 600%.^[96]^[102] A settlement was reached in 2009 with the Skokomish Indian Tribe over damages to fisheries and game habitat, damages to tribal lands through flooding, and trespass on tribal lands for the power transmission line. As part of the settlement, migrating salmon will be trucked around the dam.^[103]

The Wynoochee River was dammed in the late 1960s by the Army Corps of Engineers for flood control, but in 1994 the dam was taken over by the city of Tacoma for power generation.^[96]^[104] Migrating salmon are trucked around the dam, and Tacoma Public Utilities funds mitigation for Roosevelt elk wintering habitat that was lost under the reservoir.^[105]

With the building of the Spruce Railroad during World War I and the completion of the Olympic Highway in 1931, logging in the Olympics intensified, along with demand for recreational facilities.^[86] During this period the Forest Service built roads and campgrounds and encouraged private businesses with special use permits to build tourist facilities such as a winter sports facility at Deer Park and the chalets in Enchanted Valley and at Low Divide. Special use permits were also issued for private summer cabins at Lakes Cushman and Quinault, and the Olympic Hot Springs resort. During the Great Depression, the Olympic National Forest used the Civilian Conservation Corps to build logging roads and railroads, bridges, campgrounds, shelters, fire lookouts, ranger stations, and a fish hatchery. They also fought fires and planted tree seedlings.^[86]

Pressure for a National Park built with the acceleration of logging and road building.^[75] The Forest Service campaigned in peninsula logging and mill towns against the National Park, and both the Forest Service and the Park Service jockeyed for public support and endorsement from various conservation groups for administration of the Monument.^[86] In 1935, a special committee was convened on the National Park proposal. The majority reported that the Olympics fully rated protection as a National Park, but one member issued a minority report stating that public pressure for recreational facilities would require the Park Service to build roads, campgrounds, and chalets, thus negating any benefit from National Park status.^[86] Both the Forest Service and the Park Service sponsored backcountry trips through the high Olympics that summer to promote their stewardship of the mountains.

In 1937, President Franklin D. Roosevelt visited the Olympics to determine their suitability as a National Park, and was greeted in Port Angeles by more than 3000 local school children asking him to ‘give us our Olympic National Park’.^[75] He signed Olympic National Park into law in 1938. In 1953, the park was enlarged with the addition of the coastal strip,^[97] and more coastal areas along Lake Ozette were added in 1976.^[75] Also that year, UNESCO named the Park an International Biosphere Reserve, and a World Heritage Site in 1981. In 1984, Congress designated 5 wilderness areas in the Olympic National Forest,^[75] and declared 95% of Olympic National Park a wilderness area in 1988.^[97]

^ ^a ^b Toledo, Victor. "Mexico Regional Overview". Retrieved 16 March 2012.
^ "Topogrpahy and Drainage". Retrieved 16 March 2012.
^ Hildebrand, Robert. "Did westward subduction cause Cretaceous – Tertiary orogeny in the North American Cordillera" (PDF). Retrieved 13 March 2012.
^ Gajdusek (January 1953). "Sierra Tarahumara". Geographical Review. 43 (1). JSTOR 211536.
^ "Mexico's Copper Canyon". 2012. Retrieved 15 March 2012.
^ Standish, Peter (2009). The states of Mexico: a reference guide to history and culture. Greenwood Publishing Group. ISBN 978-0-313-34223-3.
^ Mathiasen (2010). "First Report of White Fir Dwarf Mistletoe (Arceuthobium abietinum f. sp. concoloris) on Mexican Spruce (Picea mexicana) in Northern Mexico". Retrieved 15 March 2012.
^ Valenzuela, Luis. "Going back to my roots". Retrieved 15 March 2012.
^ "Cerro Barajas, Mexico". Retrieved 21 March 2012.
^ González-Elizondo, Martha; Jurado, Enrique; Návar, José; González-Elizondo, Socorro; Villanueva, José; Aguirre, Oscar; Jiménez, Javier (2005). "Tree-rings and climate relationships for Douglas-fir chronologies from the SierraMadreOccidental, Mexico: A 1681–2001 rain reconstruction". Forest Ecology and Management. 213: 39–53. doi:10.1016/j.foreco.2005.03.012. Retrieved 21 March 2012.
^ "Cerro Gordo, Mexico". Retrieved 21 March 2012.
^ "Relieve, Durango". Retrieved 21 March 2012.
^ Stephens, Michele. "As long as the have their land". Retrieved 10 February 2013.
^ Henry, Christopher; Aranda-Gomez, Jorge (2000). "Plate interactions control middle-late Miocene, proto-Gulf and Basin and Range extension in the southern Basin and Range" (PDF). Tectonophysics. 318: 1–26. doi:10.1016/S0040-1951(99)00304-2. Retrieved 10 February 2013.
^ Canseco-Marquez, L.; Smith, Eric; Ponce-Campos, P.; Flores-Villela, O.; Campbell, Jonathan (2007). "A New Species of Tantilla (Squamata: Colubridae) of the calamarina Group from Volcan Ceboruco, Nayarit, Mexico" (PDF). Journal of Herpetology. 41 (2): 220–224. doi:10.1670/0022-1511(2007)41[220:ANSOTS]2.0.CO;2. Retrieved 10 February 2013.
^ Addams, Lee (2005). "Evaluating Increased Groundwater Use in the Yaqui Valley, Mexico" (PDF). Southwest Hydrology. Retrieved 17 March 2012.
^ ^a ^b ^c Benke, Arthur; Cushing, Colbert (2005). Rivers of North America. Academic Press. p. 1036. ISBN 978-0-08-045418-4.
^ Cisneros, Ruben (2011). "Provenance and Origin of Holocene Beach Ridge and Modern Beach Sands from the Costa de Nayarit, Western Mexico" (PDF). Retrieved 15 March 2012.
^ Gutierrez-Garcia; Villanueve-Diaz; Stahle; Therrell; Cleaveland; Estrada-Avalos; Jasso-Ibarra (2005). Hydroclimatic variability of the upper Nazas basin: Water management implications for the irrigated area of the Comarca Lagunera, Mexico. Retrieved 19 March 2012.
^ ^a ^b ^c ^d Gonzales-Barrios; Descroix; Viramontes; Anaya (2002). Soil degradation and desertification in the Western Sierra Madre of Mexico. 17th WCSS 14–21 August. Thailand.
^ Fuentes; Mena (2006). Seals for Aguamilpa, el Cajon y La Parota concrete face dams, in Mexico. Taylor & Francis. p. 573. ISBN 978-0-415-40423-5.
^ Velasquez, Aleman; Mogollon, Marengo (2006). Studies and geotechnical design of the El Cajon Dam. Taylor & Francis. p. 153. ISBN 978-0-415-40423-5.
^ Wolfe, "Mikael" (2010). "Mining Water for the Revolution: Marte R. Gomez And the Business of Agrarian REform in "La Laguna," Mexico, 1920s to 1960s" (PDF). The Helen Kellogg Institute for International Studies. Retrieved 19 March 2012.
^ "Mexican Deforestation in the Sierra Madre". 1996. Retrieved 15 March 2012.
^ Smith, Jeffrey (Winter 2008). "Barrance del Cobre" (PDF). Retrieved 9 February 2013.
^ Merril, William. "Tarahumara" (PDF).
^ Let's Go Mexico. Macmillan. 27 November 2007. ISBN 978-0-312-37452-5.
^ "El Salto". Retrieved 9 February 2013.
^ "Copala". 2001. Retrieved 9 February 2013.
^ Warner, Rick (September 2001). Jesuits and Coras in Colonial Nayarit (PDF). Latin American Studies Association. Retrieved 16 February 2013.
^ "Huajimic". Retrieved 16 February 2013.
^ Lopez, Leonel (8 May 2007). "Technical Report for the San Martín de Bolaños Silver Mine, State of Jalisco, México" (PDF). Retrieved 16 February 2013.
^ ^a ^b ^c McDowell, Fred (2007). "Geologic transect across the northern Sierra Madre Occidental volcanic field, Chihuahua and Sonora, Mexico" (PDF). GSA.
^ Roalson, Eric; Devender, Thomas; Reina G., Ana (2002). "Additions to the Cyperaceae and Juncaceae Flora of the Rio Mayo Region, Sonora, Mexico" (PDF). SIDA. 1: 339–347.
^ "Road Improvements Continue in Mexico".
^ Swanson, Eric; Keizer, Richard; Lyons, James; Clabaugh (1978). "Tertiary Volcanism and Caldera Development near Durango City, Sierra Madre Occidental, Mexico" (PDF). 1978. 89: 1000–1012. Retrieved 21 October 2012.
^ ^a ^b ^c ^d ^e "The North American Monsoon" (PDF). National Weather Service. Retrieved 7 January 2012.
^ ^a ^b ^c Garatuza-Payan, Jaime; Pinker, Rachel; Watts, Christopher (December 2001). "Solar radiation and évapotranspiration in northern Mexico estimated from remotely sensed measurements of cloudiness" (PDF). Retrieved 15 March 2012.
^ ^a ^b ^c ^d Heyerdahl, Emily; Alvarado, Ernesto (2003). "Influence of Climate and Land Use on Historical Surface Fires in Pine-Oak Forests, Sierra Madre Occidental, Mexico" (PDF).
^ "Integrated Environmental Plan for the Mexican-U.S. Border Area" (PDF). 1992. Retrieved 21 October 2012.
^ "Sierra Madre Occidental pine-oak forests". 1 December 2006. Retrieved 15 March 2012.
^ ^a ^b ^c ^d ^e Douglas, Michael; Maddox, Robert; Howard, Kenneth; Reyes, Sergio (1992). "The Mexican Monsoon" (PDF). Journal of Climate. 6 (8): 1665. doi:10.1175/1520-0442(1993)006<1665:TMM>2.0.CO;2. Retrieved 19 March 2012.
^ ^a ^b Fawcett, Peter; Stalker, James; Gutzler, David (2002). "Multistage moisture transport into the interior of northern Mexico during the North American summer monsoon". Geophysical Research Letters. 29 (23). doi:10.1029/2002GL015693.
^ ^a ^b Nesbitt, Stephen; Gochis, David; Lang, Timothy (2007). "The Diurnal Cycle of Clouds and Precipitation along the Sierra Madre Occidental Observed during NAME-2004: Implications for Warm Season Precipitation Estimation in Complex Terrain". Journal of Hydrometeorology. 9 (4): 728. doi:10.1175/2008JHM939.1. Retrieved 19 March 2012.
^ "Geology". Bronco Gold and Silver. Retrieved 15 March 2012.
^ ^a ^b ^c ^d Swanson, Eric; Kempter, Kirt; McDowell, Fred; McIntosh, William (7 March 2006). "Major ignimbrites and volcanic centers of the Copper Canyon area: a view into the core of Mexico's Sierra Madre Occidental". Geological Society of America. {{cite web}}: Missing or empty |url= (help)
^ ^a ^b ^c ^d Centeno-Garcia; Guerrero-Suastegui; Talavera-Mendoza (2008). "The Guerrero Composite Terrane of western Mexico: Collision and subsequent rifting in a supra-subduction zone" (PDF).
^ Albrecht, Achim; Goldstein, Steven (1 July 2000). "Effects of basement composition and age on silicic magmas across an accreted terrane-Precambrian crust boundary, Sierra Madre Occidental, Mexico". Journal of South American Earth Sciences. 13 (3): 255–273. doi:10.1016/S0895-9811(00)00014-6.
^ ^a ^b ^c ^d ^e ^f ^g Ferrari, Luca; Valencia-Moreno, Martin; Bryan, Scott (2007). "Magmatism and tectonics of the Sierra Madre Occidental and its relation with the evolution of the western margin of North America" (PDF). Geological Society of America. Retrieved (7 January 2012). {{cite web}}: Check date values in: |accessdate= (help)
^ Davis, J.S.; Roeske, S.M.; McClelland, W.C.; Snee, L.W. (2000). "Closing the ocean between the Precordillera terrane and Chilenia: Early Devonian ophiolite emplacement and deformation in the SW Precordillera". {{cite journal}}: Cite journal requires |journal= (help)
^ Centeno-Garcia, Elena; Corona-Chavez, Pedro; Talavera-Mendoza, Oscar; Iriondo, Alex (2003). "Geology and Tectonic Evolution of the Western Guerrero Terrane—a Transect from Puerto Vallarta to Zihuatanejo, Mexico" (PDF).
^ ^a ^b ^c Potra, Adriana (2011). "Isotopic Studies of the Guerrero Composite Terrane, West-Central Mexico: Implications for Provenance of Crustal Rocks and Genesis of Ore Metals".
^ Keppie, J. (2004). "Terranes of Mexico Revisited: A 1.3 Billion Year Odyssey" (PDF). International Geology Review. 46 (9): 765–794. doi:10.2747/0020-6814.46.9.765.
^ ^a ^b Freydier, C.; Lapierra, H.; Ruiz, J.; Tardy, M.; Martinez, J.; Coulon, C. (2000). "The Early Cretaceous Arperos basin: an oceanic domain dividing the Guerrero arc from nuclear Mexico evidenced by the geochemistry of the lavas and sediments" (PDF). Journal of South American Earth Sciences. 13 (4–5): 325–336. doi:10.1016/S0895-9811(00)00027-4.
^ ^a ^b ^c ^d Ferrari, Luca; Pasquare, Giorgio; Venegas-Salgado, Saul; Romero-Rios, Francisco (1999). "Geology of the western Mexican Volcanic Belt and adjacent Sierra Madre Occidental and Jalisco Block". "Geological Society of America". {{cite web}}: Missing or empty |url= (help)
^ ^a ^b Cosca, Michael; Cardellach, Esteve; Canals, Angels; Cardellach, E.; Canals, A. (2003). "Ages of Epithermal Deposits in Mexico: Regional Significande and Links with the Evolution of Tertiary Volcanism". Economic Geology. 98 (5): 1029–1037. doi:10.2113/gsecongeo.98.5.1029.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l McDowell, Fred; Clabaugh, Stephen (1981). "Igneous History of the Sierra Madre Occidental" (PDF). Revista Mexicana de Ciencias Geológicas. 5 (2): 195–206. ISSN 1026-8774. Retrieved 15 March 2012.
^ Aguirre-Diaz, Gerardo; Labarthe-Hernandez, Guillermo; Torres, Ramon (2002). "Basin and Range Fissure-Source Origin for Voluminous Ignimbrites of the Sierra Madre Ocidental, Mexico". Retrieved 15 March 2012.
^ Swanson, Eric (2002). "Correlation between the Tomochic and Copper Canyon Areas, the Sierra Madre Occidental, Chihuahua, Mexico". Retrieved 15 March 2012.
^ Knott, J.R.; Sarna-Wojcicki, A.M.; Machette, M.N.; Klinger, R.E. (2005). "Upper Neogene Stratigraphy and Tectonics of Death Valley – a review" (PDF). Retrieved 15 March 2012.
^ ^a ^b Nieto-Samaniego, Ángel; Ferrari, Luca; Alaniz-Alvarez, Susana; Labarthe-Henández, Guillermo; Rosas-Elguera, José (1999). "Variation of Cenozoic Extension and Volcanism across the Southern Sierra Madre Occidental Volcanic Province, Mexico" (PDF). Geological Society of America Bulletin. 111 (3): 347–363. doi:10.1130/0016-7606(1999)111<0347:VOCEAV>2.3.CO;2. Retrieved 17 February 2013.
^ ^a ^b Ferrari, Luca; Lopez-Martınez, Margarita; Rosas-Elguera, Jose (2002). "Ignimbrite flare-up and deformation in the southern Sierra Madre Occidental, western Mexico: Implications for the late subduction history of the Farallon plate" (PDF). Tectonics. 21 (4): 17–1. doi:10.1029/2001TC001302.
^ Montgomery, David; Lopez-Blanco, Jorge (2003). "Post-Oligocene river incision, Southern Sierra Madre Occidental" (PDF). Geomorphology. 55 (1–4): 235–247. doi:10.1016/S0169-555X(03)00142-9. Retrieved 20 March 2012.
^ ^a ^b ^c ^d Hawley, John (1969). Notes on the Geomorphology and Late Cenozoic Geology of Northwestern Chihuahau (PDF). 20th Field Conference, New Mexico Geological Society. Retrieved 20 March 2012.
^ ^a ^b Aguirre-Diaz, Gerardo; Labarthe-Hernandez, Guillermo (2003). "Fissure ignimbrites: Fissure-source origin for voluminous ignimbrites of the Sierra Madre Occidental and its relationship with Basin and Range faulting". Geology. 31 (9): 773–776. doi:10.1130/G19665.1.
^ Nieto-Samaniego, Angel; Alaniz-Álvarez, Susana; Camprubi, Antoni (2007). "Mesa Central of México: Stratigraphy, structure, and Cenozoic tectonic evolution" (PDF).
^ Campbell, Patricia; Anderson, Thomas (2003). "Structure and kinematics along a segment of the Mojave-Sonora megashear: A strike-slip fault that truncates the Jurassic continental magmatic arc of southwestern North America". Tectonics. 22 (7): n/a. doi:10.1029/2002TC001367.
^ ^a ^b ^c ^d ^e ^f ^g ^h Damon, Paul; Foster, C. Thomas; Damon, Paul E. (June 1982). "Cenozoic mineral deposits and subduction-related magmatic arcs in Mexico" (PDF). GSA Bulletin. 93 (6): 533–544. doi:10.1130/0016-7606(1982)93<533:CMDASM>2.0.CO;2.{{cite journal}}: CS1 maint: date and year (link)
^ Scheubel, Frank; Clark, Kenneth; Porter, Elise (1988). "Geology, Tectonic Environment, and Structural Controls in the San Martin de Bolafios District, Jalisco, Mexico". Economic Geology. 83 (8): 1703–1720. doi:10.2113/gsecongeo.83.8.1703. Retrieved 23 October 2012.
^ ^a ^b Huspeni, Jeffrey; Kesler, Stephen; Ruiz, Joaquin; Tuta, Zane; Sutter, John; Jones, Lois (1984). "Petrology and geochemistry of rhyolites associated with tin mineralization in northern Mexico". Economic Geology. 79 (1): 87–105. doi:10.2113/gsecongeo.79.1.87.
^ ^a ^b ^c Descroix, L; Viramontes, D; Vauclin, M; Gonzalez Barrios, J.L; Esteves, M (2000). "Influence of soil surface features and vegetation on runoff and erosion in the Western Sierra Madre (Durango, Northwest Mexico)". CATENA. 43 (2): 115. doi:10.1016/S0341-8162(00)00124-7.
^ Goldberg, Deborah (1982). "The Distribution of Evergreen and Deciduous Trees Relative to Soil Type: An Example from the Sierra Madre, Mexico, and a General Model". Ecological Society of America. 63: 942–951. JSTOR 1937234.
^ Pajares, Pedro (2011). "Highlands and Drylands: Mountains a source of resilience in arid regions" (PDF). Retrieved 18 October 2012.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p Franklin and Dyrness (1988). Natural Vegetation of Oregon and Washington. Corvallis, Oregon: Oregon State University Press.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z McNulty, Tim (1999). Olympic National Park: A Natural History. Seattle, Washington: University of Washington Press. ISBN 978-0-295-98887-0.
^ "Temperate Rain Forests". National Park Service. Retrieved 16 Feb 2013.
^ ^a ^b ^c "Olympic Coast Rainforest". Olympic Coast Alliance. 2005. Retrieved 17 Feb 2013.
^ ^a ^b ^c ^d Henderson, Jan A. (1989). Forested Plant Associations of the Olympic National Forest. Olympia, Washington: United States Department of Agriculture Forest Service Pacific Northwest Region.
^ ^a ^b Schultz (1990). The Northwest Coast: A Natural History. Portland, Oregon: Timber Press. ISBN 0-88192-418-0.
^ ^a ^b Fonda; Bliss (1969). "Forest Vegetation of the Montane and Subalpine Zones, Olympic Mountains, Washington". Ecological Monographs. 39 (3): 271–301. Retrieved 17 Feb 2013.
^ "Subalpine Forests". National Park Service. Retrieved 17 Feb 2013.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Cite error: The named reference mathews was invoked but never defined (see the help page).
^ ^a ^b Lewis, Jeffrey (2010). Olympic Fisher Reintroduction Project: 2010 Progress Report. Olympia, Washington: Washington Department of Fish and Wildlife.
^ ^a ^b Washington Department of Fish and Wildlife. "Washington Gray Wolf Conservation and Management". Washington Department of Fish and Wildlife. Retrieved 16 November 2013.
^ Washington Department of Fish and Wildlife. "Mountain Goats - Living with Wildlife". Washington Department of Fish and Wildlife. Retrieved 16 November 2013.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Rooney, J. R. (2007). Frontier Legacy: History of the Olympic National Forest 1897 to 1960. Seattle, Washington: Northwest Interpretive Association. ISBN 978-0-914019-58-9. Cite error: The named reference "rooney" was defined multiple times with different content (see the help page).
^ Olympic National Park (2011). Mountain Goat Action Plan (PDF). National Park Service.
^ "Trail closed by aggressive goats reopens to hikers". KOMO News (Seattle, Washington). Retrieved 23 November 2013.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k Wood, Robert (1976). Across the Olympic Mountains; the Press Expedition, 1889-1890. Seattle, WA: The Mountaineers Press. ISBN 0-916890-11-2.
^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Wood, Robert (1976). Men, Mules and Mountains: Lieutenant O'Neil's Olympic Expeditions. Seattle, Washington: The Mountaineers Press. ISBN 0-916890-43-0.
^ Cite error: The named reference ONPFisher2007 was invoked but never defined (see the help page).
^ ^a ^b ^c Olympic Peninsula Intertribal Cultural Advisory Committee (2002). Wray, Jacilee (ed.). Native Peoples of the Olympic Peninsula: Who We Are. Norman, Oklahoma: University of Oklahoma Press. ISBN 0-8061-3552-2.
^ ^a ^b ^c Meany, Edmond (1923). Origin of Washington Geographic names.
^ Meany, Edmund (1927). The Pacific Northwest.
^ Mary Metz; Kris Fulsaas, eds. (2006). Olympic Mountains: A Climbing Guide. The Mountaineers Books. Retrieved 28 Feb 2013.
^ ^a ^b ^c ^d Cite error: The named reference wood was invoked but never defined (see the help page).
^ ^a ^b ^c ^d "Mount Olympus National Monument". National Park Service. 12 Sep 2007. Retrieved 28 Feb 2013.
^ Nelson, L.A. (1907). "The Ascent of Mount Olympus". Retrieved 28 Feb 2013.
^ Department of the Interior, Olympic National Park. "History of the Elwha". National Park Service. Retrieved 11 December 2013.
^ Department of the Interior, Olympic National Park. "Elwha Fisheries". National Park Service. Retrieved 11 December 2013.
^ Department of the Interior, Olympic National Park. "Elwha River Restoration". National Park Service. Retrieved 11 December 2013.
^ "Cushman Hydro Project". Tacoma Public Utilities. Retrieved 11 December 2013.
^ "Cushman Hydro Project". Tacoma Public Utilities. Retrieved 11 December 2013.
^ "Wynoochee River Project". Tacoma Public Utilities. Retrieved 11 December 2013.
^ "Wynoochee River Project". Tacoma Public Utilities. Retrieved 11 December 2013.

[Centres_of_Plant_Diversity-1] Toledo, Victor. "Mexico Regional Overview". Retrieved 16 March 2012.

[Topography_and_Drainage-2] "Topogrpahy and Drainage". Retrieved 16 March 2012.

[HildebrandKTOro-3] Hildebrand, Robert. "Did westward subduction cause Cretaceous – Tertiary orogeny in the North American Cordillera" (PDF). Retrieved 13 March 2012.

[Gajdusek1953-4] Gajdusek (January 1953). "Sierra Tarahumara". Geographical Review. 43 (1). JSTOR 211536.

[WildInqCopCan-5] "Mexico's Copper Canyon". 2012. Retrieved 15 March 2012.

[Standish2009-6] Standish, Peter (2009). The states of Mexico: a reference guide to history and culture. Greenwood Publishing Group. ISBN 978-0-313-34223-3.

[Mathiasen2010-7] Mathiasen (2010). "First Report of White Fir Dwarf Mistletoe (Arceuthobium abietinum f. sp. concoloris) on Mexican Spruce (Picea mexicana) in Northern Mexico". Retrieved 15 March 2012.

[Valenzuela-8] Valenzuela, Luis. "Going back to my roots". Retrieved 15 March 2012.

[PBBarajas-9] "Cerro Barajas, Mexico". Retrieved 21 March 2012.

[Jurado2005-10] González-Elizondo, Martha; Jurado, Enrique; Návar, José; González-Elizondo, Socorro; Villanueva, José; Aguirre, Oscar; Jiménez, Javier (2005). "Tree-rings and climate relationships for Douglas-fir chronologies from the SierraMadreOccidental, Mexico: A 1681–2001 rain reconstruction". Forest Ecology and Management. 213: 39–53. doi:10.1016/j.foreco.2005.03.012. Retrieved 21 March 2012.

[PBGordo-11] "Cerro Gordo, Mexico". Retrieved 21 March 2012.

[12] "Relieve, Durango". Retrieved 21 March 2012.

[StephensLand-13] Stephens, Michele. "As long as the have their land". Retrieved 10 February 2013.

[Henry2000-14] Henry, Christopher; Aranda-Gomez, Jorge (2000). "Plate interactions control middle-late Miocene, proto-Gulf and Basin and Range extension in the southern Basin and Range" (PDF). Tectonophysics. 318: 1–26. doi:10.1016/S0040-1951(99)00304-2. Retrieved 10 February 2013.

[Canseco2007-15] Canseco-Marquez, L.; Smith, Eric; Ponce-Campos, P.; Flores-Villela, O.; Campbell, Jonathan (2007). "A New Species of Tantilla (Squamata: Colubridae) of the calamarina Group from Volcan Ceboruco, Nayarit, Mexico" (PDF). Journal of Herpetology. 41 (2): 220–224. doi:10.1670/0022-1511(2007)41[220:ANSOTS]2.0.CO;2. Retrieved 10 February 2013.

[Adams2005-16] Addams, Lee (2005). "Evaluating Increased Groundwater Use in the Yaqui Valley, Mexico" (PDF). Southwest Hydrology. Retrieved 17 March 2012.

[Benke2005-17] Benke, Arthur; Cushing, Colbert (2005). Rivers of North America. Academic Press. p. 1036. ISBN 978-0-08-045418-4.

[Cisneros2011-18] Cisneros, Ruben (2011). "Provenance and Origin of Holocene Beach Ridge and Modern Beach Sands from the Costa de Nayarit, Western Mexico" (PDF). Retrieved 15 March 2012.

[Gutierrez2005-19] Gutierrez-Garcia; Villanueve-Diaz; Stahle; Therrell; Cleaveland; Estrada-Avalos; Jasso-Ibarra (2005). Hydroclimatic variability of the upper Nazas basin: Water management implications for the irrigated area of the Comarca Lagunera, Mexico. Retrieved 19 March 2012.

[Gonzales2002-20] Gonzales-Barrios; Descroix; Viramontes; Anaya (2002). Soil degradation and desertification in the Western Sierra Madre of Mexico. 17th WCSS 14–21 August. Thailand.

[Fuentes2006-21] Fuentes; Mena (2006). Seals for Aguamilpa, el Cajon y La Parota concrete face dams, in Mexico. Taylor & Francis. p. 573. ISBN 978-0-415-40423-5.

[Velasquez2006-22] Velasquez, Aleman; Mogollon, Marengo (2006). Studies and geotechnical design of the El Cajon Dam. Taylor & Francis. p. 153. ISBN 978-0-415-40423-5.

[Wolfe2010-23] Wolfe, "Mikael" (2010). "Mining Water for the Revolution: Marte R. Gomez And the Business of Agrarian REform in "La Laguna," Mexico, 1920s to 1960s" (PDF). The Helen Kellogg Institute for International Studies. Retrieved 19 March 2012.

[MexDefAU1996-24] "Mexican Deforestation in the Sierra Madre". 1996. Retrieved 15 March 2012.

[Smith2008-25] Smith, Jeffrey (Winter 2008). "Barrance del Cobre" (PDF). Retrieved 9 February 2013.

[26] Merril, William. "Tarahumara" (PDF).

[27] Let's Go Mexico. Macmillan. 27 November 2007. ISBN 978-0-312-37452-5.

[28] "El Salto". Retrieved 9 February 2013.

[29] "Copala". 2001. Retrieved 9 February 2013.

[30] Warner, Rick (September 2001). Jesuits and Coras in Colonial Nayarit (PDF). Latin American Studies Association. Retrieved 16 February 2013.

[31] "Huajimic". Retrieved 16 February 2013.

[32] Lopez, Leonel (8 May 2007). "Technical Report for the San Martín de Bolaños Silver Mine, State of Jalisco, México" (PDF). Retrieved 16 February 2013.

[McDowell2007-33] McDowell, Fred (2007). "Geologic transect across the northern Sierra Madre Occidental volcanic field, Chihuahua and Sonora, Mexico" (PDF). GSA.

[Roalson2002-34] Roalson, Eric; Devender, Thomas; Reina G., Ana (2002). "Additions to the Cyperaceae and Juncaceae Flora of the Rio Mayo Region, Sonora, Mexico" (PDF). SIDA. 1: 339–347.

[35] "Road Improvements Continue in Mexico".

[Swanson1978-36] Swanson, Eric; Keizer, Richard; Lyons, James; Clabaugh (1978). "Tertiary Volcanism and Caldera Development near Durango City, Sierra Madre Occidental, Mexico" (PDF). 1978. 89: 1000–1012. Retrieved 21 October 2012.

[NOAANAM-37] "The North American Monsoon" (PDF). National Weather Service. Retrieved 7 January 2012.

[Garatuza2001-38] Garatuza-Payan, Jaime; Pinker, Rachel; Watts, Christopher (December 2001). "Solar radiation and évapotranspiration in northern Mexico estimated from remotely sensed measurements of cloudiness" (PDF). Retrieved 15 March 2012.

[Heyerdahl2003-39] Heyerdahl, Emily; Alvarado, Ernesto (2003). "Influence of Climate and Land Use on Historical Surface Fires in Pine-Oak Forests, Sierra Madre Occidental, Mexico" (PDF).

[USPO1992-40] "Integrated Environmental Plan for the Mexican-U.S. Border Area" (PDF). 1992. Retrieved 21 October 2012.

[eoearth-41] "Sierra Madre Occidental pine-oak forests". 1 December 2006. Retrieved 15 March 2012.

[Douglas1992-42] Douglas, Michael; Maddox, Robert; Howard, Kenneth; Reyes, Sergio (1992). "The Mexican Monsoon" (PDF). Journal of Climate. 6 (8): 1665. doi:10.1175/1520-0442(1993)006<1665:TMM>2.0.CO;2. Retrieved 19 March 2012.

[Fawcett2002-43] Fawcett, Peter; Stalker, James; Gutzler, David (2002). "Multistage moisture transport into the interior of northern Mexico during the North American summer monsoon". Geophysical Research Letters. 29 (23). doi:10.1029/2002GL015693.

[Nesbitt2007-44] Nesbitt, Stephen; Gochis, David; Lang, Timothy (2007). "The Diurnal Cycle of Clouds and Precipitation along the Sierra Madre Occidental Observed during NAME-2004: Implications for Warm Season Precipitation Estimation in Complex Terrain". Journal of Hydrometeorology. 9 (4): 728. doi:10.1175/2008JHM939.1. Retrieved 19 March 2012.

[BroncoGold-45] "Geology". Bronco Gold and Silver. Retrieved 15 March 2012.

[Swanson2006-46] Swanson, Eric; Kempter, Kirt; McDowell, Fred; McIntosh, William (7 March 2006). "Major ignimbrites and volcanic centers of the Copper Canyon area: a view into the core of Mexico's Sierra Madre Occidental". Geological Society of America. {{cite web}}: Missing or empty |url= (help)

[Centeno2008-47] Centeno-Garcia; Guerrero-Suastegui; Talavera-Mendoza (2008). "The Guerrero Composite Terrane of western Mexico: Collision and subsequent rifting in a supra-subduction zone" (PDF).

[Albrecht2000-48] Albrecht, Achim; Goldstein, Steven (1 July 2000). "Effects of basement composition and age on silicic magmas across an accreted terrane-Precambrian crust boundary, Sierra Madre Occidental, Mexico". Journal of South American Earth Sciences. 13 (3): 255–273. doi:10.1016/S0895-9811(00)00014-6.

[Ferrari2007-49] ^ ^a ^b ^c ^d ^e ^f ^g Ferrari, Luca; Valencia-Moreno, Martin; Bryan, Scott (2007). "Magmatism and tectonics of the Sierra Madre Occidental and its relation with the evolution of the western margin of North America" (PDF). Geological Society of America. Retrieved (7 January 2012). {{cite web}}: Check date values in: |accessdate= (help)

[50] Davis, J.S.; Roeske, S.M.; McClelland, W.C.; Snee, L.W. (2000). "Closing the ocean between the Precordillera terrane and Chilenia: Early Devonian ophiolite emplacement and deformation in the SW Precordillera". {{cite journal}}: Cite journal requires |journal= (help)

[Centeneo2003-51] Centeno-Garcia, Elena; Corona-Chavez, Pedro; Talavera-Mendoza, Oscar; Iriondo, Alex (2003). "Geology and Tectonic Evolution of the Western Guerrero Terrane—a Transect from Puerto Vallarta to Zihuatanejo, Mexico" (PDF).

[Potra2011-52] Potra, Adriana (2011). "Isotopic Studies of the Guerrero Composite Terrane, West-Central Mexico: Implications for Provenance of Crustal Rocks and Genesis of Ore Metals".

[Keppie-53] Keppie, J. (2004). "Terranes of Mexico Revisited: A 1.3 Billion Year Odyssey" (PDF). International Geology Review. 46 (9): 765–794. doi:10.2747/0020-6814.46.9.765.

[Freydier2000-54] Freydier, C.; Lapierra, H.; Ruiz, J.; Tardy, M.; Martinez, J.; Coulon, C. (2000). "The Early Cretaceous Arperos basin: an oceanic domain dividing the Guerrero arc from nuclear Mexico evidenced by the geochemistry of the lavas and sediments" (PDF). Journal of South American Earth Sciences. 13 (4–5): 325–336. doi:10.1016/S0895-9811(00)00027-4.

[Ferrari1999-55] Ferrari, Luca; Pasquare, Giorgio; Venegas-Salgado, Saul; Romero-Rios, Francisco (1999). "Geology of the western Mexican Volcanic Belt and adjacent Sierra Madre Occidental and Jalisco Block". "Geological Society of America". {{cite web}}: Missing or empty |url= (help)

[Cosca2003-56] Cosca, Michael; Cardellach, Esteve; Canals, Angels; Cardellach, E.; Canals, A. (2003). "Ages of Epithermal Deposits in Mexico: Regional Significande and Links with the Evolution of Tertiary Volcanism". Economic Geology. 98 (5): 1029–1037. doi:10.2113/gsecongeo.98.5.1029.

[McDowell1981-57] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l McDowell, Fred; Clabaugh, Stephen (1981). "Igneous History of the Sierra Madre Occidental" (PDF). Revista Mexicana de Ciencias Geológicas. 5 (2): 195–206. ISSN 1026-8774. Retrieved 15 March 2012.

[Aguirra2002-58] Aguirre-Diaz, Gerardo; Labarthe-Hernandez, Guillermo; Torres, Ramon (2002). "Basin and Range Fissure-Source Origin for Voluminous Ignimbrites of the Sierra Madre Ocidental, Mexico". Retrieved 15 March 2012.

[Swanson2002-59] Swanson, Eric (2002). "Correlation between the Tomochic and Copper Canyon Areas, the Sierra Madre Occidental, Chihuahua, Mexico". Retrieved 15 March 2012.

[Knott2005-60] Knott, J.R.; Sarna-Wojcicki, A.M.; Machette, M.N.; Klinger, R.E. (2005). "Upper Neogene Stratigraphy and Tectonics of Death Valley – a review" (PDF). Retrieved 15 March 2012.

[NietoSam1999-61] Nieto-Samaniego, Ángel; Ferrari, Luca; Alaniz-Alvarez, Susana; Labarthe-Henández, Guillermo; Rosas-Elguera, José (1999). "Variation of Cenozoic Extension and Volcanism across the Southern Sierra Madre Occidental Volcanic Province, Mexico" (PDF). Geological Society of America Bulletin. 111 (3): 347–363. doi:10.1130/0016-7606(1999)111<0347:VOCEAV>2.3.CO;2. Retrieved 17 February 2013.

[Ferrari2002-62] Ferrari, Luca; Lopez-Martınez, Margarita; Rosas-Elguera, Jose (2002). "Ignimbrite flare-up and deformation in the southern Sierra Madre Occidental, western Mexico: Implications for the late subduction history of the Farallon plate" (PDF). Tectonics. 21 (4): 17–1. doi:10.1029/2001TC001302.

[Montgomery2001-63] Montgomery, David; Lopez-Blanco, Jorge (2003). "Post-Oligocene river incision, Southern Sierra Madre Occidental" (PDF). Geomorphology. 55 (1–4): 235–247. doi:10.1016/S0169-555X(03)00142-9. Retrieved 20 March 2012.

[Hawley1969-64] Hawley, John (1969). Notes on the Geomorphology and Late Cenozoic Geology of Northwestern Chihuahau (PDF). 20th Field Conference, New Mexico Geological Society. Retrieved 20 March 2012.

[Aguirre2003-65] Aguirre-Diaz, Gerardo; Labarthe-Hernandez, Guillermo (2003). "Fissure ignimbrites: Fissure-source origin for voluminous ignimbrites of the Sierra Madre Occidental and its relationship with Basin and Range faulting". Geology. 31 (9): 773–776. doi:10.1130/G19665.1.

[66] Nieto-Samaniego, Angel; Alaniz-Álvarez, Susana; Camprubi, Antoni (2007). "Mesa Central of México: Stratigraphy, structure, and Cenozoic tectonic evolution" (PDF).

[67] Campbell, Patricia; Anderson, Thomas (2003). "Structure and kinematics along a segment of the Mojave-Sonora megashear: A strike-slip fault that truncates the Jurassic continental magmatic arc of southwestern North America". Tectonics. 22 (7): n/a. doi:10.1029/2002TC001367.

[Clark1982-68] ^ ^a ^b ^c ^d ^e ^f ^g ^h Damon, Paul; Foster, C. Thomas; Damon, Paul E. (June 1982). "Cenozoic mineral deposits and subduction-related magmatic arcs in Mexico" (PDF). GSA Bulletin. 93 (6): 533–544. doi:10.1130/0016-7606(1982)93<533:CMDASM>2.0.CO;2.{{cite journal}}: CS1 maint: date and year (link)

[69] Scheubel, Frank; Clark, Kenneth; Porter, Elise (1988). "Geology, Tectonic Environment, and Structural Controls in the San Martin de Bolafios District, Jalisco, Mexico". Economic Geology. 83 (8): 1703–1720. doi:10.2113/gsecongeo.83.8.1703. Retrieved 23 October 2012.

[Huspeni1984-70] Huspeni, Jeffrey; Kesler, Stephen; Ruiz, Joaquin; Tuta, Zane; Sutter, John; Jones, Lois (1984). "Petrology and geochemistry of rhyolites associated with tin mineralization in northern Mexico". Economic Geology. 79 (1): 87–105. doi:10.2113/gsecongeo.79.1.87.

[Descroix2000-71] Descroix, L; Viramontes, D; Vauclin, M; Gonzalez Barrios, J.L; Esteves, M (2000). "Influence of soil surface features and vegetation on runoff and erosion in the Western Sierra Madre (Durango, Northwest Mexico)". CATENA. 43 (2): 115. doi:10.1016/S0341-8162(00)00124-7.

[Goldberg1982-72] Goldberg, Deborah (1982). "The Distribution of Evergreen and Deciduous Trees Relative to Soil Type: An Example from the Sierra Madre, Mexico, and a General Model". Ecological Society of America. 63: 942–951. JSTOR 1937234.

[Pajares2011-73] Pajares, Pedro (2011). "Highlands and Drylands: Mountains a source of resilience in arid regions" (PDF). Retrieved 18 October 2012.

[franklin-74] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p Franklin and Dyrness (1988). Natural Vegetation of Oregon and Washington. Corvallis, Oregon: Oregon State University Press.

[mcnulty-75] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k ^l ^m ⁿ ^o ^p ^q ^r ^s ^t ^u ^v ^w ^x ^y ^z McNulty, Tim (1999). Olympic National Park: A Natural History. Seattle, Washington: University of Washington Press. ISBN 978-0-295-98887-0.

[NPSTempRainFor-76] "Temperate Rain Forests". National Park Service. Retrieved 16 Feb 2013.

[Gavin2001-77] "Olympic Coast Rainforest". Olympic Coast Alliance. 2005. Retrieved 17 Feb 2013.

[henderson-78] Henderson, Jan A. (1989). Forested Plant Associations of the Olympic National Forest. Olympia, Washington: United States Department of Agriculture Forest Service Pacific Northwest Region.

[schultz-79] Schultz (1990). The Northwest Coast: A Natural History. Portland, Oregon: Timber Press. ISBN 0-88192-418-0.

[Fonda1969-80] Fonda; Bliss (1969). "Forest Vegetation of the Montane and Subalpine Zones, Olympic Mountains, Washington". Ecological Monographs. 39 (3): 271–301. Retrieved 17 Feb 2013.

[NPSSubalpFor-81] "Subalpine Forests". National Park Service. Retrieved 17 Feb 2013.

[mathews-82] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Cite error: The named reference mathews was invoked but never defined (see the help page).

[fisher-83] Lewis, Jeffrey (2010). Olympic Fisher Reintroduction Project: 2010 Progress Report. Olympia, Washington: Washington Department of Fish and Wildlife.

[Washington_Department_of_Fish_and_Wildlife-84] Washington Department of Fish and Wildlife. "Washington Gray Wolf Conservation and Management". Washington Department of Fish and Wildlife. Retrieved 16 November 2013.

[85] Washington Department of Fish and Wildlife. "Mountain Goats - Living with Wildlife". Washington Department of Fish and Wildlife. Retrieved 16 November 2013.

[rooney-86] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ Rooney, J. R. (2007). Frontier Legacy: History of the Olympic National Forest 1897 to 1960. Seattle, Washington: Northwest Interpretive Association. ISBN 978-0-914019-58-9. Cite error: The named reference "rooney" was defined multiple times with different content (see the help page).

[87] Olympic National Park (2011). Mountain Goat Action Plan (PDF). National Park Service.

[88] "Trail closed by aggressive goats reopens to hikers". KOMO News (Seattle, Washington). Retrieved 23 November 2013.

[press-89] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j ^k Wood, Robert (1976). Across the Olympic Mountains; the Press Expedition, 1889-1890. Seattle, WA: The Mountaineers Press. ISBN 0-916890-11-2.

[oneil-90] ^ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j Wood, Robert (1976). Men, Mules and Mountains: Lieutenant O'Neil's Olympic Expeditions. Seattle, Washington: The Mountaineers Press. ISBN 0-916890-43-0.

[ONPFisher2007-91] Cite error: The named reference ONPFisher2007 was invoked but never defined (see the help page).

[wray-92] Olympic Peninsula Intertribal Cultural Advisory Committee (2002). Wray, Jacilee (ed.). Native Peoples of the Olympic Peninsula: Who We Are. Norman, Oklahoma: University of Oklahoma Press. ISBN 0-8061-3552-2.

[Meany1923-93] Meany, Edmond (1923). Origin of Washington Geographic names.

[Meany1927-94] Meany, Edmund (1927). The Pacific Northwest.

[95] Mary Metz; Kris Fulsaas, eds. (2006). Olympic Mountains: A Climbing Guide. The Mountaineers Books. Retrieved 28 Feb 2013.

[wood-96] Cite error: The named reference wood was invoked but never defined (see the help page).

[NPS2007-97] "Mount Olympus National Monument". National Park Service. 12 Sep 2007. Retrieved 28 Feb 2013.

[Nelson1907-98] Nelson, L.A. (1907). "The Ascent of Mount Olympus". Retrieved 28 Feb 2013.

[99] Department of the Interior, Olympic National Park. "History of the Elwha". National Park Service. Retrieved 11 December 2013.

[100] Department of the Interior, Olympic National Park. "Elwha Fisheries". National Park Service. Retrieved 11 December 2013.

[101] Department of the Interior, Olympic National Park. "Elwha River Restoration". National Park Service. Retrieved 11 December 2013.

[102] "Cushman Hydro Project". Tacoma Public Utilities. Retrieved 11 December 2013.

[103] "Cushman Hydro Project". Tacoma Public Utilities. Retrieved 11 December 2013.

[104] "Wynoochee River Project". Tacoma Public Utilities. Retrieved 11 December 2013.

[105] "Wynoochee River Project". Tacoma Public Utilities. Retrieved 11 December 2013.

[1]

[2]

[3]

[4]

[5]

[6]

[7]

[8]

[9]

[10]

[11]

[12]

[13]

[14]

[15]

[16]

[17]

[18]

[19]

[20]

[21]

[22]

[23]

[24]

[25]

[26]

[27]

[28]

[29]

[30]

[31]

[32]

[33]

[34]

[35]

[36]

[37]

[38]

[39]

[40]

[41]

[42]

[43]

[44]

[45]

[46]

[47]

[48]

[49]

[50]

[51]

[52]

[53]

[54]

[55]

[56]

[57]

[58]

[59]

[60]

[61]

[62]

[63]

[64]

[65]

[66]

[67]

[68]

[69]

[70]

[71]

[72]

[73]

[74]

[75]

[76]

[77]

[78]

[79]

[80]

[81]

[82]

[83]

[84]

[85]

[86]

[87]

[88]

[89]

[90]

[91]

[92]

[93]

[94]

[95]

[96]

[97]

[98]

[99]

[100]

@@ Line 60: / Line 60: @@
 ===Climate===
+The climate varies considerably between the northern and southern extents of this long mountain range. Seasonal variations also occur due to the presence of large bodies of warm water delivering warm damp air from each side of the range. This region undergoes a seasonal variety with two wet seasons, including a summer [[monsoon]], and two dry seasons each year.
-Precipitation varies greatly throughout the range, from the wet western slopes to the arid eastern ridges.  Mount Olympus, nearly {{convert|8,000|ft|m}} tall, is a mere {{convert|35|mi|km}} from the Pacific Ocean, one of the steepest reliefs globally and accounting for the high precipitation of the area, as much as {{convert|240|in|mm}} of snow and rain on Mount Olympus.<ref name=mcnulty>{{cite book|last=McNulty|first=Tim|title=Olympic National Park:  A Natural History|year=2009|publisher=University of Washington Press|location=Seattle, Washington|isbn=978-0-295-98887-0}}</ref>  {{convert|140|and|170|in|mm}} of rain falls on the [[Hoh Rainforest]] annually,<ref>{{cite web|url=http://www.nps.gov/olym/planyourvisit/visiting-the-hoh.htm|title=Visiting the Hoh Rainforest|publisher=U.S. National Park Service|accessdate=2011-01-27}}</ref> receiving the most precipitation of anywhere in the continental United States.<ref name = WRCC>{{cite web|title=Climate of Washington|publisher=Western Regional Climate Center|url = http://www.wrcc.dri.edu/narratives/WASHINGTON.htm|accessdate = 18 Feb 2013}}</ref> Areas to the northeast of the mountains are located in a [[rain shadow]] and receive as little as {{convert|16|in|mm|abbr=on}} of precipitation.<ref>{{cite web| url=http://www.wrcc.dri.edu/cgi-bin/cliMAIN.pl?wa7544| title=SEQUIM 2 E, WASHINGTON Climate Summary| publisher=Western Regional Climate Center| accessdate=2011-01-27}}</ref> Annual precipitation increases to about {{convert|30|in|mm|abbr=on}} on the edges of the rain shadow around Port Townsend, the San Juan Islands, and Everett.<ref name = WRCC/> 80% of precipitation falls during the winter. On the coastal plain, the winter temperature stays between {{convert|-2|to|7|C|F}}. During the summer it warms up to stay between {{convert|10|and|24|C|F}}.<ref name = Hellwig2010>{{cite thesis|title=The Interaction of Climate, Tectonics, and Topography in the Olympic Mountains of Washing State|last=Hellwig|first=Jessica|type=Masters|date=2010|url=https://www.ideals.illinois.edu/bitstream/handle/2142/16163/Hellwig_Jessica.pdf|accessdate=18 Feb 2013}}</ref>
+===Temperature, Pressure, and Wind===
-As a consequence of the high precipitation is the large number of snowfields and [[glacier]]s, reaching down to 1,500 m (5,000&nbsp;ft) above sea level. There are about 266 glaciers crowning the Olympics peaks. The most prominent glaciers are those on [[Mount Olympus (Washington)|Mount Olympus]] covering approximately {{convert|10|sqmi|km2}}. Beyond the Olympic complex are the glaciers of [[Carrie Glacier|Mount Carrie]], the Bailey Range, [[Mount Christie (Washington)|Mount Christie]], and [[Mount Anderson (Washington)|Mount Anderson]].<ref name=usgs>{{cite web|url=http://vulcan.wr.usgs.gov/Volcanoes/Washington/OlympicMountains/description_olympic_mountains.html|title=Olympic Mountains|publisher=[[USGS]]|accessdate=2009-03-01}}</ref>
+Air pressure changes in [[Northern Mexico]] and the [[Southwest United States]] are the main causes of seasonal variation in the Sierra Madre. A [[high pressure area]] that rests over the mountains in the winter begins to move north of the mountains into [[New Mexico]] during the month of June.<ref name = "NOAANAM">{{cite web | title = The North American Monsoon | publisher = National Weather Service | url = http://www.cpc.ncep.noaa.gov/products/outreach/Report-to-the-Nation-Monsoon_aug04.pdf | accessdate =7 January 2012}}</ref> The high pressure begins to breakdown and move south during September or October; however, the breakdown is usually at a slower pace than the movement north. This high pressure belt is associated with the mechanics that form the [[Bermuda High]].<ref name = "Garatuza2001">{{cite web | title = Solar radiation and évapotranspiration in northern Mexico estimated from remotely sensed measurements of cloudiness | last = Garatuza-Payan | first = Jaime | last2 = Pinker | first2 = Rachel | last3 = Watts | first3 = Christopher | date = December 2001 | url = http://iahs.info/hsj/460/hysj_46_03_0465.pdf | accessdate =15 March 2012 }}</ref>
+The climate in the mountains is mild. Summer temperatures maintain a constant level. Maximum temperatures are typically in July at around 31&nbsp;C<ref name = "Garatuza2001"/> with average temperatures on the order of 16&nbsp;C during this same period.<ref name = "Heyerdahl2003"/> Mean annual temperatures are between {{convert|55|-|65|F|C}} above {{convert|6000|ft|m}}.<ref name = USPO1992>{{cite web|title = Integrated Environmental Plan for the Mexican-U.S. Border Area|year = 1992|url = http://pdf.usaid.gov/pdf_docs/PNABM228.pdf|accessdate = 21 October 2012}}</ref> Below freezing temperatures can occur in the higher mountains, with [[precipitation (meteorology)|precipitation]] occurring as snowfall certain times of year.<ref name = "eoearth">{{cite web | title = Sierra Madre Occidental pine-oak forests | date = 1 December 2006 | url = http://www.eoearth.org/article/Sierra_Madre_Occidental_p | accessdate =15 March 2012}}</ref>
+During the summer monsoon, [[wind]] patterns undergo large scale changes.<ref name = "NOAANAM"/> In May there is very little large scale wind current through the mountains, most circulates around the mountains,<ref name = "NOAANAM"/> although [[Sea breeze|onshore flow]] is present.<ref name = "Douglas1992">{{Cite journal | title = The Mexican Monsoon | last = Douglas | first = Michael | last2 = Maddox | first2 = Robert | last3 = Howard | first3 = Kenneth | last4 = Reyes | first4 = Sergio | year = 1992 | url = http://climateknowledge.org/NA_precipitation/Douglas_Mexican_Monsoon_JClim_1993.pdf | accessdate =19 March 2012 |doi=10.1175/1520-0442(1993)006<1665:TMM>2.0.CO;2 | volume = 6 | pages = 1665 | journal = Journal of Climate | issue = 8}}</ref> As the high pressure moves north, air is pulled off the Gulf of Mexico, bringing easterly winds aloft to the mountains.<ref name = "NOAANAM"/> On the east slope of the mountain daytime upslope winds flow to the crest, where the flow joins westerly winds.<ref name = "Fawcett2002">{{Cite journal| title = Multistage moisture transport into the interior of northern Mexico during the North American summer monsoon | last = Fawcett | first = Peter | last2 = Stalker | first2 = James | last3 = Gutzler | first3 = David | year = 2002 | doi=10.1029/2002GL015693| journal = Geophysical Research Letters| volume = 29| issue = 23}}</ref> The mountains cause convection during the following monsoon season,<ref name = "Douglas1992"/> during which nocturnal winds at low levels in the atmosphere move moisture overnight.<ref name = "Fawcett2002"/> After the high pressure breaks down, wind patterns return to those prior to the monsoon season.
+=== Precipitation and Humidity===
+Precipitation varies on both annual and seasonal scales in the Sierra Madre. Annual differences in regional climate are associated with the [[El Niño-Southern Oscillation]] with El Niño years leading to a wetter climate.<ref name = "Heyerdahl2003">{{cite web | title =  Influence of Climate and Land Use on Historical Surface Fires in Pine-Oak Forests, Sierra Madre Occidental, Mexico | last = Heyerdahl | first = Emily | last2 = Alvarado | first2 = Ernesto | url = http://www.fs.fed.us/rm/pubs_other/rmrs_2003_heyerdahl_e001.pdf | year = 2003 }}</ref> Monsoon rains come to the Sierra Madre in June, as the high pressure area moves north, leading to wet summer seasons. This causes east winds bringing [[moisture]] from the [[Gulf of Mexico]]. On the western side of the mountains, which are affected by the largest change in precipitation between the [[dry season]] and monsoon season,<ref name = "Douglas1992"/> in the monsoon season rainfall can exceed {{convert|30|cm|in|abbr = on}} in a single month.<ref name = "NOAANAM"/> The southern region receives more of the rainfall than the northern.<ref name = "Douglas1992"/> Much of this precipitation occurs as [[tropical storms]]. As the high pressure over New Mexico breaks down, rainfall in the Sierra Madre end. Because of the monsoon, the summer accounts for the majority of rainfall in the area.<ref name = "Heyerdahl2003"/> The spring and fall dry season separate out a weaker wet season in the winter. In addition to increasing in the southern ranges of the mountains, rainfall increases in the higher elevations of the Sierra Madre Occidental.<ref name = "Heyerdahl2003"/>
+[[Humidity]] in the mountains varies at wide levels as does rainfall. In the early morning before dawn, the air is almost saturated (often over 90% [[relative humidity]]) near the mountain tops with low clouds over the range. Lower in the range, air is not as near saturated in the morning.<ref name = "Nesbitt2007">{{cite journal | title = The Diurnal Cycle of Clouds and Precipitation along the Sierra Madre Occidental Observed during NAME-2004: Implications for Warm Season Precipitation Estimation in Complex Terrain | last = Nesbitt | first = Stephen | last2 = Gochis | first2 = David | last3 = Lang | first3 = Timothy | year = 2007 | url = http://journals.ametsoc.org/doi/pdf/10.1175/2008JHM939.1 | accessdate =19 March 2012 | doi=10.1175/2008JHM939.1 | journal = Journal of Hydrometeorology | volume = 9 | issue = 4 | pages = 728}}</ref> Seasonal variation in humidity is also present with average May and June relative humidity around 50%, with 25% possible during the day.<ref name = "Garatuza2001"/> Also during the day, relative humidity drops and cloud levels rise as temperatures rise.<ref name="Nesbitt2007"/> The humidity of the range is also influenced by the same seasonal changes as rainfall. In the dry season [[dew point]]s are low, around −22 °C in the south of the range and −24 °C to −26 °C in the north in May. In June, dew points begin to increase from the May levels up to −20 °C in the North and −16 °C in the south. By July these dew points are at −14 °C throughout the range. The range allows higher dew points throughout these periods than the surrounding low lands. This rise in humidity accompanies the monsoon.<ref name = "Douglas1992"/>
 ==Geology==