Talk:Paleocene–Eocene Thermal Maximum

From Wikipedia, the free encyclopedia
Jump to: navigation, search
WikiProject Environment (Rated B-class)
WikiProject icon This environment-related article is part of the WikiProject Environment to improve Wikipedia's coverage of the environment. The aim is to write neutral and well-referenced articles on environment-related topics, as well as to ensure that environment articles are properly categorized.
Read Wikipedia:Contributing FAQ and leave any messages at the project talk page.
B-Class article B  This article has been rated as B-Class on the project's quality scale.
 ???  This article has not yet received a rating on the project's importance scale.
WikiProject Geology (Rated Start-class, Mid-importance)
WikiProject icon Paleocene–Eocene Thermal Maximum is part of WikiProject Geology, an attempt at creating a standardized, informative, comprehensive and easy-to-use geology resource. If you would like to participate, you can choose to edit this article, or visit the project page for more information.
Start-Class article Start  This article has been rated as Start-Class on the project's quality scale.
 Mid  This article has been rated as Mid-importance on the project's importance scale.


"as far north as 80°N."[edit]

Could somebody give a realistic idea of how far north this is? Like give the name of a country at that level? Robinoke 10:31, 25 Feb 2005 (UTC)

After the five years that have elapsed since this question, we now have a nice article about 80th parallel north. --Teratornis (talk) 01:42, 2 October 2010 (UTC)

Global Warming[edit]


Did Paleocene-Eocene Thermal Maximum cause any notable transgression of oceans onto the continents? It is very a interesting question with respect to global warming and the rising of oceans. Stepanovas 10:42, 17 December 2005 (UTC) The Cretaceous and the Paleocene did not have polar ice caps, so there were no ice reserves to melt and raise sea levels worldwide. Warmer oceans do expand somewhat. --Wetman 05:51, 27 July 2006 (UTC)

What is the Antarctic Ocean? I assume they meant Arctic.

I think you are right too, although I am not an expert, but I do recall (see my note below) Tim Flannery's preoccupation with the Arctic - not the Antarctic - when discussing this same PETM event so I have changed it myself. It has been a long time since you posted and no one else has been around to respond or do so. Finally, all of the links similarly seem to refer to the north pole i.e. northern oceans also! Mattjs 04:35, 21 February 2007 (UTC)


I guess this could represent the runaway greenhouse effect ? 07:40, 31 August 2007 (UTC)

I guess it couldn't, because the greenhouse effect did not, in fact, run away. -- Zimriel (talk) 02:32, 16 May 2008 (UTC)
Depends what you mean by 'runaway' - a runaway train eventually stops after all. — Preceding unsigned comment added by (talk) 22:51, 5 April 2012 (UTC)

And furthermore[edit]

That "1,500 to 2,000 gigatons of carbon released into the ocean/atmosphere system over the course of 1,000 years" -- could that not be related to the warming of the oceans, easily releasing that volume of CO2 over that span? Is it not a violation of NPOV to throw that particular cart in front of the horse, comparing it to human CO2 production?

All the CO2 we've produced in the last 300 years has resulted in an increase from 0.03% (preindustrial) to 0.04% of atmospheric gases. We're currently producing a little over 3% of all CO2 production in the world. [1] We could be responsible for a bit more, by killing things that then decay. —Preceding unsigned comment added by Oiler99 (talkcontribs) 06:53, 5 November 2009 (UTC)

You seem to be confusing net CO2 production with gross. The natural carbon cycle moves huge amounts of CO2 between sources and sinks each year, but the natural sources and sinks have been much closer to equilibrium for most of geological history than they are now, as human additions of CO2 are not being fully taken out by natural sinks. For example, each year in the northern hemisphere the autumn leaf drop releases an amount of carbon exceeding man's current annual fossil fuel budget - but most of this carbon is taken back up during the next growing season, giving little net change from year to year. The analogy is to consider a bank account from which someone withdraws large amounts of money repeatedly but then deposits it all back. Over time, the account balance would remain stable despite the meaningless churning of the account. However, if the account holder then began depositing just a little extra, while keeping the large withdrawals and deposits the same as before, the account balance would begin steadily ticking up. That's how humans have managed to increase the atmospheric concentration of CO2 to a higher level than has existed in the past 800,000 years and probably for the last 20 million years. A seemingly small change from 0.026% to 0.04% can have quite substantial long-term impact, as similar magnitude changes in the opposite direction correlated with the site of present-day Chicago being under a mile of ice. --Teratornis (talk) 00:51, 2 October 2010 (UTC)


Asteroid Impact(s)[edit]

Tim Flannery mentions this extinction event early in his book on global warming The Weather Makers refering to evidence/research that suggests a nothern hemishpere (north atlantic i believe) oceanic impact or impacts that heated the ocean and/or directly heated oceanic/coastal methane and methane hydrate reserviors. Yet nowhere is this evidence/theory however briefly mentioned in the article? Maybe I will come back and do so when I have a hardcopy to cite with the reference (I currently only have an audiobook). If anyone knows anything or has it also then please include it. Interestingly Image:Extinction Intensity.png doesn't include a -55M peak either. Regards, Mattjs 04:15, 21 February 2007 (UTC)

Looks like someone else agreed with me but this time a comet. Would be a nice addition if it came with a supportable reference - guess I will just have to find it in The Weather Makers again and then add and/or amend this users edit. Mattjs 17:13, 22 February 2007 (UTC)

Methane release[edit]

Found a reference to this nature published study that apparently proves the cause of the event was a massive methane release. The origin of the methane release is still not proven, also the author favor the hypothesis of a surface source : the microbes' sudden switch to methane for their diet indicates they were swamped by a local source of the gas. The explanation for this is a snap release from terrestrial sources, rather than a longer release of methane from the sea or underground, according to Pancost.

Nature : Increased terrestrial methane cycling at the Palaeocene–Eocene thermal maximum

AFP Greenhouse Earth: Methane powered runaway global warming — Preceding unsigned comment added by (talk) 18:03, 25 October 2011 (UTC)

Would the Nature (journal) article be useful at Tipping point (climatology)? (talk) 03:32, 29 October 2011 (UTC)

The claim that 'careful examination of the Thomas et al. data set shows that there is not a single intermediate planktonic foram value, implying that the perturbation and attendant δ13C anomaly happened over the lifespan of a single foram' appears to be original research by synthesis of data from a published paper.

Volcanic Activity[edit]

Official excerpt from the book "Waking the Giant" (Bill McGuire 2009) "Accompanying the event, wholesale melting in the Earth’s mantle underlying the waking the giant region fed vast outpourings of lava across Canada’s Baffin Island, Greenland, the Faeroes, and north-west Britain. In places, lavas were piled more than seven kilometres thick, while elsewhere magma intruded en masse into the local rock and sediments. Estimates suggest that the total volume of magma involved was staggering, ranging between 5 and 10 million cubic kilometres. Impressive, undoubtedly, but what has this to do with the PETM? According to Mike Storey of Roskilde University in Denmark, and colleagues, quite a lot. Storey and his fellow researchers propose that the puzzle of the initial PETM warming can be explained by the release of prodigious volumes of carbon-12 enriched methane as magma associated with the splitting of Greenland from Europe heated and baked carbon-rich sediments that floored much of the region prior to the tectonic upheaval. The timing is just about right, with the start of the PETM occurring a little after the beginning of the great, magmatic outburst."–giant.pdf Prokaryotes (talk) 04:35, 2 January 2014 (UTC)


Terrestrial extinctions or not?[edit]

Intro: "Many benthic foraminifera and terrestrial mammals became extinct"

4.5 Life: "There is no evidence of any increased extinction rate among the terrestrial biota."

Surely these are contradictory statements?

The "Norwegian Blue"[edit]

During a hot period at 55 mya there is, now, in Denmark of all places, a wingbone of the first parrot.[1] Any chance of seeing this in the article? Seems to me to be topical - unless we are assuming two warming periods within 800,000 years of each other, one of which affected only Denmark. I posted it a mite too fast and perhaps in the wrong section of this article. I was going to wikify my primary source but someone edited it out faster than I could fix it. Anyway, my link here is the better-formatted version I'd posted in the parrot page... -- Zimriel (talk) 02:32, 16 May 2008 (UTC)

  1. ^ Waterhouse, D.W. (2008). "Two new fossil parrots (Psittaciformes) from the Lower Eocene Fur Formation of Denmark". Palaeontology 51: 575-582. 51: 575–582.  Unknown parameter |coauthors= ignored (|author= suggested) (help)


maths or unit wrong[edit]

>At this location, the PETM CIE, from start to end, spans about 2 m.[6] Long-term age constraints, through biostratigraphy and magnetostratigraphy, suggest an average Paleogene sedimentation rate of about 1.2 cm/yr. Assuming a constant sedimentation rate, the entire event, from onset though termination, was therefore estimated at about 200,000 years

I make that 200 years. I think the sedimentation rate may be per century. — Preceding unsigned comment added by (talk) 20:50, 12 June 2014 (UTC)

Dead link[edit]

During several automated bot runs the following external link was found to be unavailable. Please check if the link is in fact down and fix or remove it in that case!

maru (talk) contribs 05:00, 27 July 2006 (UTC)

I deleted the broken link and added two functioning ones --Wetman 05:49, 27 July 2006 (UTC)

AKA: LPTM[edit]

Late Paleocene thermal maximum (LPTM), as per [2]
~ender 2007-07-07 23:00:PM MST

Comparison with current anthropogenic carbon emissions[edit]

Paleocene–Eocene Thermal Maximum#Evidence for carbon addition mentions a carbon addition range from about 2500 to over 6800 gigatons. The lead section calls the PETM "perhaps the best past analog in which to understand the fate and consequences of current fossil fuel emissions on an intermediate time-scale (>1000 years)." I think it be useful, then, to list the current annual, cumulative to date, and projected carbon emissions from fossil fuel combustion, for comparison. Does anyone else have opinions about whether and how to work this information in to the article? --Teratornis (talk) 00:30, 2 October 2010 (UTC)

Lysocline or CCD?[edit]

Is it not the CCD that is reflected explicitly in geological records and not the Lysocline? Whilst you're at it, if you are in the know about these things could you please have a look at a related question of mine using the link below:



--Andrew F. (talk) 23:06, 26 April 2011 (UTC)

Another link on CO2 withdrawal and sequestration following PETM onset[edit]

See here: Earth Recovered from Prehistoric Global Warming Faster Than Previously Thought. ~AH1 (discuss!) 01:46, 7 May 2011 (UTC)



World Without Ice; 56 million years ago a mysterious surge of carbon into the atmosphere sent global temperatures soaring. In a geologic eyeblink life was forever changed. by Robert Kunzig National Geographic October 2011 publishing. (talk) 23:12, 20 September 2011 (UTC)

Excerpt ... <extensive excerpt removed, per WP:NFC>
See Carbon cycle within Planetary boundaries. (talk) 01:18, 6 October 2011 (UTC)
Here is a list of wikilinks from the Quotation deleted by Special:Contributions/Arthur Rubin (see View History) ... global warming, Atlantic Ocean, primate, human beings burned, coal, oil, natural gas, fossil fuels, carbon, drought, flood, insect plagues, extinction, Life, Earth. (talk) 05:45, 9 October 2011 (UTC)

Zuni sequence reference ?[edit]

The PETM c.55Ma is associated with a marine transgression over much of North America, the Zuni sequence from 55-25Ma. Also, is not the PETM associated with the rifting open of the North Atlantic, and the final severing of North America from Europe? (talk) 19:26, 1 November 2012 (UTC)

Possible useful reference.[edit]

I've come across this paper related to this subject which might be of use in the article

To quote Calcium carbonate and carbon isotope records from the rhythmically bedded Marlboro Clay, deposited during the onset of the PETM CIE, show that the massive release of isotopically light carbon was instantaneous, providing important constraints for the magnitude of carbon released and potential mechanisms.

G-13114 (talk) 17:48, 6 October 2013 (UTC)

Here's an article about that study G-13114 (talk) 23:28, 9 October 2013 (UTC)
Someone added the study to the article, today. Prokaryotes (talk) 23:54, 9 October 2013 (UTC)
Hi! "Someone" was me :-) --Hg6996 (talk) 04:36, 10 October 2013 (UTC)


Perhaps someone could look into the research at Rutgers University. It seems to contradict this article regarding the duration of CO2 release. Or perhaps I missed something. In any case, shouldn't this recent finding be added. ? Here's the link, (talk) 03:27, 18 August 2014 (UTC)

Thanks, added. prokaryotes (talk) 12:08, 18 August 2014 (UTC)
Read a follow up study, prokaryotes (talk) 23:55, 18 August 2014 (UTC)

Possible confusing edits[edit]

A recent editor of the article, made in part wrong and confusing edits, see for instance It is unclear if the edits were made by mistake, references are lacking too. prokaryotes (talk) 13:04, 18 August 2014 (UTC) In this edit the user clearly modified a figure wrong - see the study paper which states 6800, he changed the article figure to 7000. The same edit div has him changed, quote = This model was improved using the assumption that 3He flux is constant; this cosmogenic nuclide is produced at a (roughly) constant rate by the sun, and there is little reason to assume large fluctuations in the solar wind across this short time period. TO quote = This age model was independently examined using 3He contents, assuming the flux of this cosmogenic nuclide is roughly constant over short time periods END Thus, he changed the content (added independent) and made the part about the sun influence more confusing, by removing keywords, such as the mention of the sun entirely. prokaryotes (talk) 13:21, 18 August 2014 (UTC)

Article needs more updates[edit]

There are several conclusions in the article, based on studies which can be considered out of date and need to be updated with our current understanding of the events. --prokaryotes (talk) 00:36, 19 August 2014 (UTC)

A positive spin on PETM?[edit]

"The increase in mammalian abundance is intriguing. There is no evidence of any increased extinction rate among the terrestrial biota. Increased CO2 levels may have promoted dwarfing[34][35] – which may have encouraged speciation. Many major mammalian orders – including the Artiodactyla, horses, and primates – appeared and spread around the globe 13,000 to 22,000 years after the initiation of the PETM.[34]"

Why not state how many species that died out instead. Putting that way makes it seem as if PETM is something good, something to strive for? Makes for a really sick idea to me. And I think it should be it for most educated people? Someone takes the 'positive aspects' of methane releases, CO2, and global warming too far there in my opinion. Never liked stupidity. (talk) Yoron. — Preceding undated comment added 00:45, 23 September 2014 (UTC)

Well, it's not stupid if the sourcing holds up. There's no "good" or "bad" in looking at these geologic events; I mean, if something else had happened, maybe humans would never have come into being, and is that good or bad? (You'd have to see the alternative I suppose) Our current ecological disruption is bringing a wide range of exciting new (mostly hybrid) invasive species into being, killer bees and such, and is that good or bad? Wnt (talk) 15:47, 14 October 2016 (UTC)

Significance of the comet paper[edit]

I assume folks have seen this/this about microtektites found in New Jersey and Florida from 56 MYA. So far the editing of the article has been understated. I am tempted to now put the comet theory first, remove the comment about it briefly being favored, have a thing about it in the lead etc. But... this isn't my field and I'm not sure how to balance this against other sources. Can we have a discussion of how far to push this?

It's a damn simple idea, a comet full of CO2 instantly causing greenhouse warming, but perhaps that simplicity is too alluring. How likely is it that that happened and something else at the same time? Wnt (talk) 15:42, 14 October 2016 (UTC)

Recent edits[edit]

I have again reverted recent edits. The first one changes the temperature comparison from a comparison between temperatures today and at the P-E Maximiun to stating the increase in temperature at the time, but the increase at the time is already covered in the next paragraph. The edit also uses the ~ symbol, which will not be familiar to many readers. The other edit seems to make a valid point but is very badly worded. It repeats the words "a main difference" in the previous sentence, and it also says "the amount of released carbon" whereas the difference is not the amount but the speed of release. Dudley Miles (talk) 08:45, 1 September 2017 (UTC)

Hi Dudley. Temperature changes, as the summary noted, are due to a missing reference - now indicated by a citation needed tag. The ~ sign is used 8 times in this article, and is commonly used elsewhere on Wikipedia. The repeated phrase has been addressed. The amount/speed figures are based on a new study, see references for more. Other than that, you also removed the new study entirely from the body, and a related image, as well as study results from Bowen 2015. prokaryotes (talk) 09:51, 1 September 2017 (UTC)