Talk:Abrupt climate change

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Triggers[edit]

  • Hi. I put a note on the alteration page for this. It needs some considerable work. More detail on the Younger Dryas and triggers of abrupt climate change such as the Thermohaline circulation and Glacial/Interglacial periods. St91 22:49, 21 February 2007 (UTC)
Yeah, it's v. much work in progress. I'm no expert on the details of THC and Younger Dryas. Any help you can offer would be coolAndrewjlockley (talk) 02:33, 22 February 2009 (UTC)

Another reference[edit]

I'll write this down on talk, since I'll probably get interrupted or distracted before I get around to figuring out how to format it for the article. Abrupt Climate Change: Inevitable Surprises (2002) [1] Dan Wylie-Sears 2 (talk) 06:24, 8 February 2009 (UTC)

It's already referenced, mate!Andrewjlockley (talk) 02:33, 22 February 2009 (UTC)


Cause vs causes[edit]

The best current theory for the cause of abrupt climate change is the slowing of the ocean's thermohaline circulation (THC). It looks to me, as I start to read the above reference,Alley et al. as though that's only considered the cause of DO events, not of all abrupt climate change. I'll wait for confirmation before editing the article, though. Dan Wylie-Sears 2 (talk) 06:34, 8 February 2009 (UTC)

Oops, other reference. Alley et al. was already cited, so I didn't mention it above. Dan Wylie-Sears 2 (talk) 06:41, 8 February 2009 (UTC)

I think the article already makes clear there are a range of causes, but feel free to edit if you think you can improve.Andrewjlockley (talk) 02:33, 22 February 2009 (UTC)

Historic events[edit]

I've reinstated the historic events section with a qualifierAndrewjlockley (talk) 12:07, 23 February 2009 (UTC)

I've added references which appear to use the term as I've discussed. They're closed documents tho, so if anyone could check that would be coolAndrewjlockley (talk) 14:51, 23 February 2009 (UTC)
You are thereby saying that you are including references which you do not know whether support your text or not? Have you learned nothing by now?
I've reverted you reinsertion again. You wrote:
"The following events may not be regarded as abrupt climate change, because of their geographical limitations, limited impact, or short duration."
If they are not regarded as ACC, then why include them? Then you wrote:
"However, they could be considered as examples[25][26] and are included for completeness:"
As examples of what exactly? And in completeness of what? --Kim D. Petersen (talk) 16:24, 23 February 2009 (UTC)
See the citations which, as I recall, describe them as ACC. Andrewjlockley (talk) 07:22, 7 April 2009 (UTC)
Then please check the references. And cite for me the page and paragraph of those descriptions, since i have seen the citations. --Kim D. Petersen (talk) 07:46, 7 April 2009 (UTC)
A cursory glance suggest that little ice age and abrupt climate change are linked in many articles http://scholar.google.co.uk/scholar?rlz=1C1GGLS_en-GBGB301GB303&sourceid=chrome&q=little%20ice%20age%20abrupt%20climate%20change&um=1&ie=UTF-8&sa=N&hl=en&tab=ws Andrewjlockley (talk) 10:26, 7 April 2009 (UTC)
We do not need a "cursory glance" - but directly verifiable connections. Mentioning the LIA in a paleo-paper is rather common. --Kim D. Petersen (talk) 11:13, 7 April 2009 (UTC)
Do the first 3 of these http://scholar.google.co.uk/scholar?hl=en&lr=&q="little+ice+age"+"abrupt+climate+change"&btnG=Search satisfy you? Andrewjlockley (talk) 11:50, 7 April 2009 (UTC)
No William M. Connolley (talk) 12:32, 7 April 2009 (UTC)
Here is the full version of the Alley et al. paper (the first of your 3)[2] - now find the spot where the reference says that the LIA was abrupt. If you can't, then you can start explaining why you are inserting statements that aren't backed by reliable sources, and isn't in the references that you provide! --Kim D. Petersen (talk) 13:00, 7 April 2009 (UTC)

papers rmvd[edit]

pls explain rmvl of alley and lenton papers Andrewjlockley (talk) 12:44, 7 April 2009 (UTC)

I'll put them back in if no reason is given for their removal.Andrewjlockley (talk) 23:49, 7 April 2009 (UTC)

citations[edit]

WMC - please evidence your statement in lead re 'archetypal'. I've already asked you for a cite once - please don't strip out my tag as if we should take your word for it. If you don't evidence the stateemnt, I'll cut it. Andrewjlockley (talk) 23:49, 7 April 2009 (UTC)

I've done your referencing for you. You might like to note that the theory does not explain all observations. Andrewjlockley (talk) 07:44, 8 April 2009 (UTC)
If you want polite conversation, may I put it to you that using an edit comment of "drivel" is a rather poor way to begin? You might even want to apologise, perchance William M. Connolley (talk) 07:46, 8 April 2009 (UTC)
I wouldn't use language like that for anyone else, and was only trying to point out the inappropriateness of your edit and the also the personal abuse you so frequently direct at me. Please behave by the same standards you ask of others. (As it's been noted, I won't need to do it again.) As regards the edit: the objection I had was that you took it upon yourself to ascribe that event as the 'archetypal' ACC event without a citation, and to offer a cause - also without a citation. Further, you had the cheek to remove my tag when I asked you to justify it. If you look on the Younger Dryas page, you'll see that the cause you ascribed does not fully fit the data. Other editors have noted bond events (or DO) as the archetypal events, so your WP:POV was neither universal nor supported. Andrewjlockley (talk) 11:31, 8 April 2009 (UTC)
PS please don't revert my edits when they were done to support your WP:POV. Andrewjlockley (talk) 11:32, 8 April 2009 (UTC)
If you don't like REGW, pls comment here, rather than smashing links (and causing collateral damage whilst you do). Andrewjlockley (talk) 11:39, 8 April 2009 (UTC)


more dodgy tagging[edit]

how can you possibly justify tagging a paper that's solely about the 21st c risk of acc with a 'not in citation given'. I'd love to think of you as a wise old schoolmaster, carefully educating an enthusiastic but careless student. but stuff like this just makes me think that's really not the case at all. Andrewjlockley (talk) 02:14, 23 May 2009 (UTC)

Because the paper explicitly notes that its definition of tipping points isn't equal to abrupt climate change (its under the headline "Defining a Tipping Element and Its Tipping Point" (or just search for abrupt)). Do you read the papers? --Kim D. Petersen (talk) 10:20, 23 May 2009 (UTC)
Yes, but it doesn't say that ALL of them are not abrupt, does it? Some clearly are. Andrewjlockley (talk) 14:50, 23 May 2009 (UTC)
I changed the reference anyway, which you seem not to have noticed when you TP AWickert. Andrewjlockley (talk) 16:40, 23 May 2009 (UTC)
Sorry, your commentary doesn't match reality. Unless of course i have the gift of being psychic (check the timestamps) --Kim D. Petersen (talk) 16:59, 23 May 2009 (UTC)
Sorry got mixed on times. U happy now? Andrewjlockley (talk) 18:00, 23 May 2009 (UTC)

(outdent) Wow, this is complicated. Let's take a step back and define "abrupt climate change". The first sentence says that it occurs over geologically short time-scales (which, depending on who you ask, is somewhere between a few ka and 1 Ma), and then much of the article is about anthropogenic global warming and present-day threats. I believe a clarification of which it is about would greatly help the above debate. This may or may not be difficult to untangle in itself; it is possible that it will need two definitions, one for paleoclimate, and one for now. Awickert (talk) 20:01, 23 May 2009 (UTC)

Seems sensible. Abrupt in paleo includes stuff like region DO events, as well as much longer PETM and PT type events. Abrupt in context of AGW may refer to the above, but also to sudden (<decadal) events. Andrewjlockley (talk) 10:22, 24 May 2009 (UTC)
I would count DO as abrupt, but not PETM. In any event, refs needed William M. Connolley (talk) 21:31, 25 May 2009 (UTC)
First hits on google scholar show both modern studies and those of the Paleogene, so I'm saying < a few thousand years (the max. time-resolution of the Paleogene). Awickert (talk) 09:12, 26 May 2009 (UTC)
I tagged - needs a cite. Would you consider the individual spikes of the PETM abrupt, even if you don't consider the whole event to be abrupt? Andrewjlockley (talk) 12:11, 26 May 2009 (UTC)
I removed the tag as none of the refs in the article use examples longer than a few thousand years. This does include the PETM; only one spike at the boundary is the PETM - the others have other names. Unfortunately, I think that there is no definition of absolutie climate change (hence no ref) but there are enough refs that use it for rapid things in the Cenozoic (and I couldn't find counterexamples) that it can be said to be generally used for that. If you can find it used for other things, add them, then just change my text. Awickert (talk) 15:28, 26 May 2009 (UTC)
I replaced the tag as per Burden. I think that we need to be very sure it's never used for >10000yrs events before rmving.Andrewjlockley (talk) 15:43, 26 May 2009 (UTC)
Who exactly would a >10000 yr event be abrupt to? And the NRC definition rules a >1k year event out as abrupt. --Kim D. Petersen (talk) 16:44, 26 May 2009 (UTC)
Hm, so I was wrong; I found this paper using the term for extinctions. The first citation used to support my 3ka inference is actually distilled for human impact; if we use that definition, we might as well throw out the geologic part altogether. I will reword the lede again. Awickert (talk) 17:09, 26 May 2009 (UTC)
The citation is from '88 - where (iirc) for instance the PETM was thought to have happened more rapidly. I'll check up with the NRC report.. --Kim D. Petersen (talk) 17:38, 26 May 2009 (UTC)
Here's an interesting one:
Overpeck, J. T.; Cole, J. E. (2006). "Abrupt Change in Earth's Climate System". Annual Review of Environment and Resources 31: 1–31. doi:10.1146/annurev.energy.30.050504.144308.  edit
Which seems to agree with you. Although they rewrite the definition of abrupt, and base it on the assumption that the PETM was a clathrate gun. --Kim D. Petersen (talk) 17:58, 26 May 2009 (UTC)
I'll check the source. I used the new ref to talk about the P-T boundary, and although it is old and some of the proposed causes have shifted, more precise dating has generally shown more precisely that it happened rapidly (I think within about 300ka now); recent research is relating it to volcanism in the Siberian traps (emplaced through what looks like a large amount of coal). Awickert (talk) 18:23, 26 May 2009 (UTC)

I would guess that the use of the term depends on how far back you are looking. Roughly, if the change looks like a vertical spike at the resolution you have available, it is abrupt William M. Connolley (talk) 18:04, 26 May 2009 (UTC)

100% agree: it is based on the resolution, but I have yet to find a source that explicitly says that. Awickert (talk) 18:24, 26 May 2009 (UTC)
It might be an idea to separate the two parts completely, so that the geological vs. short timescale that AJL ha(s/d) so many problems with gets removed completely - with a push towards a split into Abrupt climate changes on the geological timescale (or something like that) if the section gets large enough. --Kim D. Petersen (talk) 18:32, 26 May 2009 (UTC)
Certainly we should make it clear. If we're agreed that there are these two senses, the next step is to agree that the one people care most about, and are most familiar with, is the one that matters on GW-type timescales; ie things that can happen much faster than std.gw, ie decades or less. I don't think we need a separate article yet William M. Connolley (talk) 18:50, 26 May 2009 (UTC)
The article is about climate change in general, not global warming specifically. Andrewjlockley (talk) 21:21, 26 May 2009 (UTC)

AGU Chapman Conference on Abrupt Climate Change[edit]

http://www.agu.org/meetings/chapman/2009/ccall/ might prove a useful (re)source William M. Connolley (talk) 22:44, 17 June 2009 (UTC)

anyone got a ref for ice cores?[edit]

i've seen the ice cores from the end of the younger dryas on telly but i've not seen them in a paper. anyone got a good ref for the sudden change in snow?Andrewjlockley (talk) 01:35, 1 July 2009 (UTC)

Merge discussion[edit]

The definitions, examples, and feedbacks described seem the same on these two articles. If they describe the same phenomenon, they should be merged. -Atmoz (talk) 05:33, 31 October 2009 (UTC)

Yes, the two articles describe the same thing and use a lot of the same material. They should be merged. Interestingly enough, a Google search for runaway climate change brings up 1,200,000 articles, but only 241,000 for abrupt climate change. This contrasts with a search of Google Scholar which reveals only 40,800 articles for runaway, but 126,000 for abrupt. Apparently, runaway is more of a pop media term, whereas abrupt is more commonly used by actual scientists.--CurtisSwain (talk) 21:16, 31 October 2009 (UTC)
Oppose - Runaway climate change can be slow, not abrupt. Abrupt climate change need involve no runaway effects. It would be like merging articles women and musician - they may overlap, but often don't. Andrewjlockley (talk) 02:45, 1 November 2009 (UTC)
CommentConcur There is so much overlap as it stands these articles are nearly repeating each other so my general preference would be for some sort of merge. However Andrew is right they are not the same thing so how a merge would happen is clearly something to discuss. Polargeo (talk) 12:33, 3 November 2009 (UTC)
Better to merge into runaway greenhouse effect or something similar. Abrupt just isn't the right place for it. Andrewjlockley (talk) 20:23, 4 November 2009 (UTC)
Concur per Atmoz and Curtis. "runaway" is a pop-culture wording in the way it is used here, the Earth doesn't have such a thing. Either turn runaway fully into a description of Venus (ie. how it happened) and other likely runaway scenarios and merge the rest. Or drop runaway completely. --Kim D. Petersen (talk) 12:56, 3 November 2009 (UTC)
There are sci papers referencing the term Andrewjlockley (talk) 20:23, 4 November 2009 (UTC)
concur per Atmoz and Curtis and Kim William M. Connolley (talk) 09:58, 5 November 2009 (UTC)
Oppose - fundamentally different topics. I agree the duplication should be removed, but I'd suggest that we do it by rewriting Runaway climate change to mainly describe scenarios where positive feedbacks overwhelm negative feedbacks over the long term (a la Venus, or indeed as per James Hansen's recent warnings). "Abrupt" describes speed: a rapid change from one state to another, but both may be relatively stable; this is not the case with "runaway" climate change, i.e. linear instability. Wantok (toktok) 04:31, 6 January 2010 (UTC)

So we have a consensus that the articles need to be re-worked to accurately reflect their titles. As per Wantok. Do we remove the merge thing now? These comments are all a year old... 209.6.252.192 (talk)

Major Changes[edit]

After reading and working with two distinguished professors of paleoclimate change and geology, we edited the page to make it more relevant with current ideas and information on abrupt climate change. —Preceding unsigned comment added by 129.15.131.149 (talk) 19:13, 27 February 2011 (UTC)


I also agree that major changes need to be done on this page. It is inconsistent with how abrupt climate change is being taught, especially at collegiate levels. Weather and climate are 2 very different things & this article gets them both confused. It is unclear to the reader what is considered a sudden shift in climate or weather. —Preceding unsigned comment added by 72.200.198.51 (talk) 03:09, 4 March 2011 (UTC)