skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 Steig's just looks ludicrous. For one thing, it doesn't even show the peninsula torching like it clearly has been, and then most of the continent is uniformly painted with the same degree of warming. Meanwhile, O'Donnell shows a much more detailed picture with the peninsula torching and some areas cooling. O'Donnell basically takes them to town for using statistical techniques (principal component analysis) the effects of which they don't understand. A common problem in climate science. Keep in mind Steig never intended it to perfectly preserve regional phenomenon I don't think.. but it was supposed to be accurate for the continent as a whole which it clearly wasn't. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 I see. Well, we already know that even with ENSO-corrections, there was a leveling out of global temps starting in the early 2000s. Which is why the Wood For Tree Temp Index (all four major global temp sources combined) shows a downward trend that is very similar to ENSO 2002-10. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 Antarctica is the poster child of climate model futility....there are a lot of theories of why they aren't warming...but there has yet to be a great explanation. Climate models have it warming faster than anywhere except the Arctic. Yet its not doing anything and probably slightly cooling. (though GISS disagrees with that) Well from what I understand .. climate models do predict a strengthening of the SAM in response to GHGs and ozone depletion.. it sounds to me like these simulations are an adequate explanation Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 I see. Well, we already know that even with ENSO-corrections, there was a leveling out of global temps starting in the early 2000s. Which is why the Wood For Tree Temp Index (all four major global temp sources combined) shows a downward trend that at least matches ENSO 2002-10. Yes definitely has slowed since 2002... remember this? I'd estimate the GISS-ENSO corrected trend to present at .11C/decade since 2002. Trends to present: Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 RSS doesn't include as much of the Arctic as UAH, right? If so, perhaps that explains (just as with HadCRU and GISS) we are seeing a different trend over the past decade, as RSS has seen more cooling than UAH...while before while the Arctic was colder they were showing more warming than UAH. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 RSS doesn't include as much of the Arctic as UAH, right? If so, perhaps that explains (just as with HadCRU and GISS) we are seeing a different trend over the past decade, as RSS has seen more cooling than UAH...while before while the Arctic was colder they were showing more warming than UAH. it's only 2.5 degrees with is what like .5% of the earth's surface area? I think it is mostly related to 90S-70S... I tried adjusting for it the other day and it did help explain much of the divergence but I couldn't get a perfect match. I almost PMd you about this yesterday because you and I have taken note of the UAH convergence a couple times.. but since I wasn't 100% sure it was due to 70S-90S I didn't... it still might be related to 70S-80N.. or some combination. The obvious explanation is the antarctic though. Remember RSS doesn't include anything south of 70S. I think UAH is up to 85N while RSS is 82.5N. UAH might got to 90N... either way that is a tiny tiny area. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 Yes definitely has slowed since 2002... remember this? I'd estimate the GISS-ENSO corrected trend to present at .11C/decade since 2002. Trends to present: I don't see how it would be that high. The regular GISS trend from 2002-present isn't even that high. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 it's only 2.5 degrees with is what like .5% of the earth's surface area? I think it is mostly related to 90S-70S... I tried adjusting for it the other day and it did help explain much of the divergence but I couldn't get a perfect match. Remember RSS doesn't include anything south of 70S. I think UAH is up to 85N while RSS is 82.5N. UAH might got to 90N... either way that is a tiny tiny area. Hmm, yeah that wouldn't seem to make much a difference at all. But for whatever reason, the switch from UAH to RSS running cooler seemed to happen around that same period the Arctic started warming. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 I don't see how it would be that high. The regular GISS trend from 2002-present isn't even that high. Yeah and the ENSO trend is real negative since 02.. which leads to an upwards adjustment in my model. The model's based on regular GISS, and in retrospect I agree GISS's trends this decade are biased a little high. I would prefer an average of GISS/HAD + UAH poles for this decade. Or a straight up average of GISS/HAD (it makes very little difference this decade whether we replace the poles with UAH or not). Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 Hmm, yeah that wouldn't seem to make much a difference at all. But for whatever reason, the switch from UAH to RSS running cooler seemed to happen around that same period the Arctic started warming. Remember ... divergences and convergences are caused by trends... and the arctic hasn't warmed that much since 2001... which is when a lot of the convergence occurs. The main piece of evidence for the convergence being attributed to the antarctic is that RSS and UAH sharply converged from 2001-2003, a period of sharp antarctic warming. UAH sort of experiences a "step up" in 2001-2003 relative to RSS. The Antarctic warmed like .5C from 2001-2003.. given the relatively large area of 70S-90S and the fact that UAH includes all of it and RSS none of it.. you can imagine the effect would be quite significant The area between 70S and 90S is probably close to 20X the area between 82.5N and 85N. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 Yeah and the ENSO trend is real negative since 02.. which leads to an upwards adjustment in my model. The model's based on regular GISS, and in retrospect I agree GISS's trends this decade are biased a little high. I would prefer an average of GISS/HAD + UAH poles for this decade. Or a straight up average of GISS/HAD (it makes very little difference this decade whether we replace the poles with UAH or not). But you were talking about ENSO having more of an effect on satellite temps before. And satellite trends match ENSO trends pretty well overall this past decade. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 But you were talking about ENSO having more of an effect on satellite temps before. And satellite trends match ENSO trends pretty well overall this past decade. Sorry I've lost you.. what are you saying exactly? I was just basically describing a technical detail.. for example... 98-02 I would expect satellite trends to be cooler than surface trends because the ENSO trend is negative, which would have a bigger affect on the satellites. The converse is I would expect more satellite warming during +ENSO periods.. for example 99-04 I would expect UAH to show more warming.. or 08-11. Which is exactly what we observe. One must also consider the effect of the different lags. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 Remember ... divergences and convergences are caused by trends... and the arctic hasn't warmed that much since 2001... which is when a lot of the convergence occurs. The main piece of evidence for the convergence being attributed to the antarctic is that RSS and UAH sharply converged from 2001-2003, a period of sharp antarctic warming. UAH sort of experiences a "step up" in 2001-2003 relative to RSS. The Antarctic warmed like .5C from 2001-2003.. given the relatively large area of 70S-90S and the fact that UAH includes all of it and RSS none of it.. you can imagine the effect would be quite significant The area between 70S and 90S is probably close to 20X the area between 82.5N and 85N. I'm not sure that's it. RSS started converging towards UAH the mid/late 1990s. See graphs below. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 Sorry I've lost you.. what are you saying exactly? I was just basically describing a technical detail.. for example... 02-10 or 02-09 I would expect more satellite trends to be cooler than surface trends because the ENSO trend is negative, which would have a bigger affect on the satellites. The converse is I would expect more satellite warming during +ENSO periods.. for example 99-04 I would expect UAH to show more warming.. or 07-09. Which is exactly what we observe. One must also consider the effect of the different lags. Ok, I just don't see any evidence for GISS-ENSO corrected trends since 2002 to be .11C/decade. That would diverge them even further from the rest of the sources. EDIT: Well, maybe that's about right. 2007 and 2008 they were way warmer than any of the other sources, so I guess that would contribute heavily towards the trend. Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 I'm not sure that's it. RSS started converging towards UAH the mid/late 1990s. See graphs below. More evidence: the 1997-02 trend shows RSS starting to move towards UAH. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 I'm not sure that's it. RSS started converging towards UAH the mid/late 1990s. See graphs below. Think about it though.. if you're drawing a trendline 1996-2010 and UAH experiences a step-wise increase 2001-2003... then that will show convergence for the whole trend line... even though the actual convergence mostly occurred 2001-2003. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 More evidence: the 1997-02 trend shows RSS starting to move towards UAH. Well that makes sense as I believe 1997-2002 was a period of moderate antarctic net warming. One sec... let me post a 12-month smoother graphic of antarctic temps instead of that 5 year smoother earlier in the thread. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 uah antarctica (60S-90S) 1979-present. Obviously the strong cooling 1980-1994 would introduce a strong cooling bias in UAH relative to RSS Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 Think about it though.. if you're drawing a trendline 1996-2010 and UAH experiences a step-wise increase 2001-2003... then that will show convergence for the whole trend line... even though the actual convergence mostly occurred 2001-2003. I just don't see this big spike for UAH during that time frame you are talking about.... Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 I just don't see this big spike for UAH during that time frame you are talking about.... Yeah I got it wrong.. the time period is really 1997-2002. Here I will predict convergence/divergence based solely off of Antarctic temps.. try checking them these are all based solely off antarctic temps.. if I'm right it means the convergence/divergence of UAH/RSS is dependent upon the antarctic 1980-1994... strong divergences 1991-1994... strong divergence 1996-2000.. divergence 1993-1997... convergence 1994-2002... convergence 2002-2004... divergence Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 uah antarctica (60S-90S) 1979-present. Obviously the strong cooling 1980-1994 would introduce a strong cooling bias in UAH relative to RSS But see, the overall Antarctic trend 2002-present is slightly downwards. Which would NOT favor RSS having a cooler trend, it would favor UAH, since UAH covers more of the Antarctic. Right? Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 Yeah I got it wrong.. the time period is really 1997-2002. Here I will predict convergence/divergence based solely off of Antarctic temps.. try checking them these are all based solely off antarctic temps.. if I'm right it means the convergence/divergence of UAH/RSS is dependent upon the antarctic 1980-1994... strong divergences check 1991-1994... strong divergence check 1996-2000.. divergence barely 1993-1997... convergence check 1994-2002... convergence nothing 2002-2004... divergence check Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 Yeah I got it wrong.. the time period is really 1997-2002. Here I will predict convergence/divergence based solely off of Antarctic temps.. try checking them these are all based solely off antarctic temps.. if I'm right it means the convergence/divergence of UAH/RSS is dependent upon the antarctic 1980-1994... strong divergences 1991-1994... strong divergence 1996-1999.. divergence 1994-1996... convergence 1994-2002... convergence 2002-2004... divergence 1980-94: strong divergence 1991-94: weak divergence (MUCH smaller) 1996-99: no divergence, very close 1994-96: close, though not as close as 1996 1994-02: very close trend as well, no convergence or divergence 2002-04: strong divergence EDIT: Looks like you changed some of your dates in the post above Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 1980-94: strong divergence 1991-94: weak divergence (MUCH smaller) 1996-99: no divergence, very close 1994-96: close, though not as close as 1996 1994-02: very close trend as well, no convergence or divergence 2002-04: strong divergence I got some of the start and end points wrong looking at my antarctic temps graph.. i edited them... now they all work except one (1994-2002). Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 There's definitely something else going on as well.. but I believe the inclusion of the Antarctic explains much of the differences between the two There seems to be some underlying propensity for UAH to converge since the mid 90s, regardless of the Antarctic Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 I got some of the start and end points wrong looking at my antarctic temps graph.. i edited them... now they all work except one (1994-2002). 1993-1997 is basically a matching trend, not really convergence there. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 1993-1997 is basically a matching trend, not really convergence there. It's the big y-axis due to the large overall trend making the convergence look small.. the convergence is pretty decent at ~.03C net stat to end points .. regardless I don't think we need to get too into details.. it seems to do a decent job but there is definitely something else going on as well Link to comment Share on other sites More sharing options...
tacoman25 Posted March 23, 2011 Share Posted March 23, 2011 There's definitely something else going on as well.. but I believe the inclusion of the Antarctic explains much of the differences between the two There seems to be some underlying propensity for UAH to converge since the mid 90s, regardless of the Antarctic I honestly don't see strong evidence for it. The Antarctic trends seem to match about as well as the Arctic. I would say if we filter in the AMO flip (when the Arctic began warming) and the PDO flip (NH landmasses seeing less warming), along with Antarctic trends, then it kind of makes some sense. Link to comment Share on other sites More sharing options...
skierinvermont Posted March 23, 2011 Share Posted March 23, 2011 I honestly don't see strong evidence for it. The Antarctic trends seem to match about as well as the Arctic. I would say if we filter in the AMO flip (when the Arctic began warming) and the PDO flip (NH landmasses seeing less warming), along with Antarctic trends, then it kind of makes some sense. Well tomorrow I'll try removing the antarctic for UAH.. I still think it does a decent job but it's pretty hard to tell the way we're doing it. The strong divergence UAH/RSS 1980-1995 and then subsequent moderate convergence is quite interesting to me.. surprised we don't see more about this. night Link to comment Share on other sites More sharing options...
BethesdaWX Posted March 23, 2011 Author Share Posted March 23, 2011 Are you guys using the updated/recently adjusted RSS trends and not the old ones? Due to RSS's spurious deviation, it was adjusted down a bit. Link to comment Share on other sites More sharing options...
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