Super Dual Auroral Radar Network

From Wikipedia, the free encyclopedia
Jump to: navigation, search
SuperDARN site in Holmwood SDA, Saskatoon

The Super Dual Auroral Radar Network (SuperDARN) is an international scientific radar network[1][2] consisting of 35[3] high frequency (HF) radars located in both the Northern and Southern Hemispheres. SuperDARN radars are primarily used to map high-latitude plasma convection in the F region of the ionosphere, but the radars are also used to study a wider range of geospace phenomena including field aligned currents, magnetic reconnection, geomagnetic storms and substorms, magnetospheric MHD waves, mesospheric winds via meteor ionization trails, and interhemispheric plasma convection asymmetries.[2] The SuperDARN collaboration is composed of radars operated by JHU/APL, Virginia Tech, Dartmouth College, the Geophysical Institute at the University of Alaska Fairbanks, the Institute of Space and Atmospheric Studies at the University of Saskatchewan, the University of Leicester, La Trobe University, and the Solar-Terrestrial Environment Laboratory at Nagoya University.

History[edit]

In the 1970s and 1980s, the Scandinavian Twin Auroral Radar Experiment (STARE) very high frequency (VHF) coherent scatter radars were used to study field aligned E region ionospheric irregularities. Using two radars with overlapping fields of view, it was possible to determine the 2D velocity vector of E region ionospheric plasma flow.[2] However, irregularities were only observed when the radar wavevector was perpendicular to the magnetic field in the scattering region. This meant that there was a problem with operating at VHF since VHF frequencies don't allow for very much refraction of the transmitted radar wave vector; thus, the perpendicularity requirement could not be easily met at high latitudes. At HF frequencies, however, refraction of the radar wavevector is greater, and this allows for the perpendicularity requirement to be met at high latitudes. Refraction of radio waves in the ionosphere is a complicated non-linear phenomenon governed by the Appleton–Hartree equation.

In 1983, a steerable-beam HF radar with 16 log-periodic antennas began operations at Goose Bay, Labrador, Canada.[1] Comparing measurements of F region ionopheric plasma velocity from the Goose Bay radar with the Sondestrom Incoherent Scatter Radar revealed that the Goose Bay radar was capable of measuring the F region plasma convection velocity. A magnetically conjugate radar was constructed in Antarctica at Halley Research Station in 1988 as part of the Polar Anglo–American Conjugate Experiment (PACE). PACE provided simultaneous conjugate studies of ionospheric and magnetospheric phenomena.[2]

From PACE, which was only able to determine a single component of the 2D ionospheric velocity, it became apparent that determining the 2D ionospheric velocity would be advantageous. Combining velocity measurements from Goose Bay with a second coherent-scatter radar in Schefferville in 1989 allowed for a 2D determination of the F region ionospheric velocity.

This work led to SuperDARN, a network of HF radars with pairs of radars having overlapping fields of view. This arrangement allowed for the detemination of the full 2D ionospheric plasma convection velocity. Due to the advancement of data assimilation models, radars recently added to the network do not necessarily have overlapping fields of view. Using data from all SuperDARN radars in the northern or southern hemisphere, an ionospheric plasma convection pattern—a map of high-latitude plasma velocity at F region altitudes (300 km)—can be determined.[2]

Primary Goals[edit]

The primary goals of SuperDARN are to determine or study:

  • Structure of global convection—to provide a global-scale view of the configuration of plasma convection in the high-latitude ionosphere;
  • Dynamics of global convection—to provide a global-scale view of the dynamics of plasma convection in the high-latitude ionosphere. (Previous studies of high-latitude convection had largely been statistical and time-averaged);
  • Dynamics of global convection—to provide a global-scale view of the dynamics of plasma convection in the high-latitude ionosphere. (Previous studies of high-latitude convection had largely been statistical and time-averaged);
  • Substorms—to test various theories of polar cap expansion and contraction under changing IMF conditions and observe the large-scale response of the nightside; convection pattern to substorms:
  • Gravity waves,
  • High-latitude plasma structures, and
  • Ionospheric irregularities

Operations[edit]

SuperDARN radars operate in the HF band between 8.0 MHz (37m) and 22.0 MHz (14m).[2] In the standard operating mode each radar scans through 16 beams of azimuthal separation of ~3.24°, with a scan taking 1 min to complete (~3 seconds inegration per beam). Each beam is divided into 75 (or 100) range gates each 45 km in distance, and so in each full scan the radars each cover 52° in azimuth and over 3000 km in range; an area encompassing the order of 1 millon square km.

The radars measure the Doppler velocity (and other related characteristics) of plasma density irregularities in the ionosphere.

Since Linux became popular, it has become the default operating system for the SuperDARN network. The operating system (superdarn-ros.3.6) is currently licensed under the LGPL). [1]

SuperDARN sites[edit]

The following is a list of SuperDARN sites, based on a list maintained by Virginia Tech College of Engineering.[4] As of 2009, an expansion project was underway for expanding the network into the middle latitudes, including the addition of sites in Hays, Kansas (near Fort Hays State University), Oregon, and the Azores, in order to support mapping outside of the auroral regions during large magnetic storms.[5]


Name Code Location Coordinates Boresight
Heading
Institute (website) Nationality
Northern Hemisphere
King Salmon ksr King Salmon, Alaska, United States 58°41′30″N 156°39′32″W / 58.6918°N 156.6588°W / 58.6918; -156.6588 −20.0° National Institute of Information and Communications Technology Japan
Adak Island East ade Adak Island, Alaska, United States 51°53′34″N 176°37′43″W / 51.8929°N 176.6285°W / 51.8929; -176.6285 46.0° University of Alaska Fairbanks United States
Adak Island West adw 51°53′35″N 176°37′52″W / 51.8931°N 176.6310°W / 51.8931; -176.6310 −28.0°
Kodiak kod Kodiak, Alaska, United States 57°36′43″N 152°11′29″W / 57.6119°N 152.1914°W / 57.6119; -152.1914 30.0°
Prince George pgr Prince George, British Columbia, Canada 53°58′52″N 122°35′31″W / 53.9812°N 122.5920°W / 53.9812; -122.5920 −5.0° University of Saskatchewan Canada
Saskatoon sas Saskatoon, Saskatchewan, Canada 52°09′26″N 106°31′50″W / 52.1572°N 106.5305°W / 52.1572; -106.5305 23.1°
Rankin Inlet rkn Rankin Inlet, Nunavut, Canada 62°49′41″N 92°06′47″W / 62.8281°N 92.1130°W / 62.8281; -92.1130 5.7°
Inuvik inv Inuvik, Northwest Territories, Canada 68°24′46″N 133°46′08″W / 68.4129°N 133.7690°W / 68.4129; -133.7690 26.4°
Clyde River cly Clyde River, Nunavut, Canada 70°29′N 68°30′W / 70.49°N 68.50°W / 70.49; -68.50 −55.6°
Blackstone bks Blackstone, Virginia, USA 37°06′07″N 77°57′01″W / 37.1019°N 77.9502°W / 37.1019; -77.9502 -40.0° Virginia Polytechnic Institute and State University United States
Fort Hays East fhe Hays, Kansas, United States 38°51′31″N 99°23′19″W / 38.8585°N 99.3886°W / 38.8585; -99.3886 45.0°
Fort Hays West fhw 38°51′32″N 99°23′25″W / 38.8588°N 99.3904°W / 38.8588; -99.3904 −25.0°
Goose Bay gbr Happy Valley-Goose Bay,
Newfoundland and Labrador, Canada
53°19′04″N 60°27′51″W / 53.3179°N 60.4642°W / 53.3179; -60.4642 5.0°
Kapuskasing kap Kapuskasing, Ontario, Canada 49°23′34″N 82°19′19″W / 49.3929°N 82.3219°W / 49.3929; -82.3219 −12.0°
Wallops Island wal Wallops Island, Virginia, United States 37°51′27″N 75°30′36″W / 37.8576°N 75.5099°W / 37.8576; -75.5099 35.9° Johns Hopkins University Applied Physics Laboratory United States
Stokkseyri sto Stokkseyri, Iceland 63°51′37″N 21°01′52″W / 63.8603°N 21.0310°W / 63.8603; -21.0310 −59.0° University of Leicester United Kingdom
Þykkvibær
Cutlass/Iceland
pyk Þykkvibær, Iceland 63°46′22″N 20°32′40″W / 63.7728°N 20.5445°W / 63.7728; -20.5445 30.0°
Hankasalmi
Cutlass/Finland
han Hankasalmi, Finland 62°18′50″N 26°36′19″E / 62.3140°N 26.6054°E / 62.3140; 26.6054 −12.0°
Hokkaido hok Hokkaido, Japan 43°31′54″N 143°36′52″E / 43.5318°N 143.6144°E / 43.5318; 143.6144 25.0° Nagoya University Japan
Christmas
Valley East
cve Christmas Valley, Oregon, United States 43°16′13″N 120°21′24″W / 43.2703°N 120.3567°W / 43.2703; -120.3567 54.0° Dartmouth College United States
Christmas
Valley West
cvw 43°16′15″N 120°21′31″W / 43.2707°N 120.3585°W / 43.2707; -120.3585 −20.0°
Southern Hemisphere
Name Code Location Coordinates Boresight
Heading
Institute (website) Nationality
Dome C dce Concordia Station, Antarctica 75°05′24″S 123°21′00″E / 75.090°S 123.350°E / -75.090; 123.350 115.0° Institute for Space Astrophysics and Planetology Italy
Halley* hal Halley Research Station, Antarctica 75°37′12″S 26°13′09″W / 75.6200°S 26.2192°W / -75.6200; -26.2192 165.0° British Antarctic Survey United Kingdom
McMurdo mcm McMurdo Station, Antarctica 77°50′15″S 166°39′21″E / 77.8376°S 166.6559°E / -77.8376; 166.6559 300.0° University of Alaska Fairbanks United States
South Pole sps South Pole Station, Antarctica 89°59′42″S 118°17′28″E / 89.995°S 118.291°E / -89.995; 118.291 75.7°
SANAE* san SANAE IV, Vesleskarvet, Antarctica 71°40′37″S 2°49′42″W / 71.6769°S 2.8282°W / -71.6769; -2.8282 173.2° South African National Space Agency South Africa
Syowa South* sys Showa Station, Antarctica 69°00′39″S 39°35′24″E / 69.0108°S 39.5900°E / -69.0108; 39.5900 159.0° National Institute of Polar Research Japan
Syowa East* sye 69°00′31″S 39°36′01″E / 69.0085°S 39.6003°E / -69.0085; 39.6003 106.5°
Kerguelen ker Kerguelen Islands 49°21′02″S 70°15′59″E / 49.3505°S 70.2664°E / -49.3505; 70.2664 168.0° French National Centre for Scientific Research France
TIGER tig Bruny Island, Tasmania, Australia 43°23′59″S 147°12′58″E / 43.3998°S 147.2162°E / -43.3998; 147.2162 180.0° La Trobe University Australia
TIGER-Unwin unw Awarua, near Invercargill, New Zealand 46°30′47″S 168°22′34″E / 46.5131°S 168.3762°E / -46.5131; 168.3762 227.9°
Zhongshan zho Zhongshan Station, Antarctica 69°22′36″S 76°22′05″E / 69.3766°S 76.3681°E / -69.3766; 76.3681 72.5° Polar Research Institute of China China

*: Part of the Southern Hemisphere Auroral Radar Experiment

Coverage[edit]

Northern Hemisphere

  • Because the SuperDARN network evolved in the west during the late Cold War, coverage of Russia's arctic regions is poor.
  • Although there is no shortage of possible sites to cover Russia's arctic regions from Northern Europe and Alaska, the coverage would probably not be of high quality.
  • So far there has been no movement within those managing the SuperDARN network to do joint ventures with Russian universities to build the Russian part of the network.

Southern Hemisphere

  • Although Antarctica is covered reasonably well, the Sub-Antarctic regions do not have uniform coverage.
  • Java VM real time display software interoperability (where both poles could be observed at the same time) is still a work in progress.


SuperDARN in action
Real Time Java applet display of SuperDARN network for the Americas 
The Unwin Radar is a scientific radar array at Awarua Plain near Invercargill, New Zealand 

References[edit]

  1. ^ a b Greenwald, R.A. (February 1, 1995). "DARN/SuperDARN". Space Science Reviews 71 (1-4): 761–796. doi:10.1007/BF00751350. 
  2. ^ a b c d e f Chisham, G. (January 1, 2007). "A decade of the Super Dual Auroral Radar Network (SuperDARN): scientific achievements, new techniques and future directions". Surveys in Geophysics 28 (1): 33–109. doi:10.1007/s10712-007-9017-8. 
  3. ^ Ruohoniemi, M.J. "VT SuperDARN Home: Virginia Tech SuperDARN". Retrieved February 23, 2015. 
  4. ^ "SuperDARN". Virginia Tech. Retrieved 2015-01-07. 
  5. ^ "APL Part of International Team Expanding Space Weather Radar Network". Johns Hopkins Applied Physics Laboratory. 2009-08-30. Retrieved 2015-01-07. 

Research papers[edit]

Research papers related to SuperDARN and related technologies

Real time display of SuperDarn radar

External links[edit]

Each participating university should be listed here. As these are ongoing research sites, these links are subject to change.

Northern Hemisphere Stations

Southern Hemisphere Stations


Media related to Unwin Radar at Wikimedia Commons