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Comments 109551 to 109600:
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thingadonta at 09:18 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
re #12 The statement was made to show how stupid the glacier statement was. There is an interesting quote by Dr Lal, co ordinating author of the chapter, who desipuite knowing it was dubious, states "It related to several countries in this region and their water sources. We thought that if we can highlight it, it will impact policy-makers and politicians and encourage them to take some concrete action" Read more: http://www.dailymail.co.uk/news/article-1245636/Glacier-scientists-says-knew-data-verified.html#ixzz0zpcSb8EC. To any normal thinking person, this mean exagerating for political purposes, a clear and admitted breach of IPCC prinicples. "IPCC reports should be neutral with respect to policy". Read more: http://www.dailymail.co.uk/news/article-1245636/Glacier-scientists-says-knew-data-verified.html#ixzz0zpcmLu7g I would like to use my dubious statement above, for political purposes. I am concerned about Asias energy supplies in the next few decades, and the rising threat to these from climate science, so I am going to leave it in my report to "impact policy-makers and politicians and encourage them to take some concrete action". Dr Lal should be releaved of duties and sent back to 1 -
kdkd at 09:05 AM on 18 September 2010Should The Earth Be Cooling?
Ken #14 "Just the fact that we are all niggling about whether the Earth is slightly heating or cooling over the last 8-15 years, or whether it is statistically significant is pretty good proof that the theory of CO2GHG forcing as the main driver of global warming is in serious trouble." How do you make these illogical leaps? It simply means you're asking the wrong questions. Have you considered the possibility thatyour ideological preconceptions contaminate your ability to evaluate the science in a level headed way? I might write up a post for SS on statistical power and trends in the next week or two to dispel this rubbish once and for all. -
nealjking at 09:04 AM on 18 September 2010Why positive feedback doesn't necessarily lead to runaway warming
70, TTTM: I'm not sure what you mean by "literally trapped". What is pretty clear from the radiative transfer theory is that the intensity of IR power reflects the temperature at the photosphere; so the higher the altitude, the lower the radiated power, the smaller the amount of cooling. I don't see any conflict with cirrus clouds: Just because you use a blanket doesn't mean you can't wear pajamas. -
nealjking at 08:21 AM on 18 September 2010Why positive feedback doesn't necessarily lead to runaway warming
TTTM: After some thought, I come back to the same point of view: - Increasing convection, in itself, wouldn't change the radiative forcing budget, so it wouldn't affect the global average temperature. Additional mixing would probably stir things up a bit more, spreading the heat around: So you would get "more weather". Not surprising: weather is pretty much driven by convection anyway. - The ground-level heating should increase the absolute humidity, which should result in a smaller lapse rate (rate of temperature drop with altitude): Dry air has a lapse rate of about 10-deg-C/km, whereas saturated moist air drops at about 5-deg-C/km. What this implies is that the ground-level temperature will not need to rise as much to make the radiative forcing imbalance go away. This effect can never be big enough to result in a net cooling, but it will moderate (to some extent) the warming due to the enhanced greenhouse effect. So, never let it be said that I denied ALL negative feedback loops in global warming! -
TimTheToolMan at 08:10 AM on 18 September 2010Why positive feedback doesn't necessarily lead to runaway warming
High level Cirrus clouds make a large difference to keeping the long wave energy within the atmosphere. Your ideas that the (15um) long wave energy is literally trapped within the atmosphere isn't supported by evidence (or the science) -
The contradictory nature of global warming skepticism
Rob, what I'm saying is that the 'loss' is so small (in context with the amount that the Antarctic has) as to be insignificant, and within Grace's error, surely? As of now, it's losing 0.001% of its mass. Do you really react to that with alarm, seriously? Within five years that could be reversed, and as I said, it could be in error anyway (haven't yet clicked on Daniel's link yet). Rob, reverse this. If the Antarctic were gaining 0.001% of its mass annually would you be afraid that we're heading for a new Ice Age? [Please ignore the other metrics as we're talking about the poles.] I'm willing to bet you wouldn't. I see no alarm about the poles as of now. The Antarctic looks healthy, and only time will tell on the Arctic. Certainly all the scare stories we got from what should be level-headed people after 2007 look somewhat shaky. 2008 ice was supposed to be so thin that 2009 would be disaster. Not so. Despite the thickness it recovered fairly well. 2010 is inconclusive as of now (let's see what happens in the coming weeks). But like I said, let's see what happens over the next few years. -
Riccardo at 07:04 AM on 18 September 2010What's happening to glaciers globally?
mspelto, although it may sound ovious, I wish to thank you for you invaluable contributions. There's a sentence in the conclusions of you paper that I, not being a glaciologist, could not fully understand: "The correlation coefficient in annual balance between each glacier exceeds 0.80, regardless of the extent of accumulation zone thinning, indicating annual balance alone cannot be use." My trivial picture would say that accumulation zone thinnig alone could be enough to point not just to disequilibrium but to the non-survival of a glacier. What I think I'm missing is some physical mechanism of glacier dynamics that justify the use of more sophisticated parameters. I would be gratefull if you could elaborate a bit on this. -
Rob Honeycutt at 06:58 AM on 18 September 2010The contradictory nature of global warming skepticism
Baz... So, how is it that you, with no particular expertise in ice, would come to a very different conclusion than the experts who are actually working with the data? There is very a big difference between "Antarctic ice is stable" and "Antarctic ice loss is accelerating." -
Rob Honeycutt at 06:15 AM on 18 September 2010Should The Earth Be Cooling?
Daniel... Not so important to waste time on it. I just wanted to bookmark it so I would be able to locate it in a pinch. Thx! -
Daniel Bailey at 06:11 AM on 18 September 2010Should The Earth Be Cooling?
Re: Rob Honeycutt (33) Michael Tobis ran across it somewhere & posted on it, so a bunch of us ran around trying to find the original source image (buried in a ppt somewhere). This is the source for the image that caused the controversy. I forget the thread post at OIIFTG. If it's important, I can look it up for you. The Yooper -
Rob Honeycutt at 06:05 AM on 18 September 2010Should The Earth Be Cooling?
Daniel... Do you have a source for that diagram? I had never put that together that the emergence of agriculture is timed exactly with coming out of the Younger Dryas. Let's hope we don't later have to add to the other side of the chart a captions that says "agriculture ends." -
Daniel Bailey at 05:56 AM on 18 September 2010The contradictory nature of global warming skepticism
Re: Baz (261)"As I understand it Grace reports an annual loss of 190 GT (+-77). As the Antarctic has 20,000,000 GT of ice then that 0.001% of ice is well within Grace's normal error, surely? If the Antarctic were gaining 190 GT of ice (according to Grace) then I'd say it wasn't gaining it! For me, it appears that the Antarctic is extraordinarily stable."
Actually, I covered the net (bottom of the error range) loss of Antarctica here. The majority of losses have come since 2006, so the loss is just ramping up. And many sources point to catastrophic instability in the WAIS, particularly in the PIG. Just pointing it out to, um, you. The Yooper -
Daniel Bailey at 05:48 AM on 18 September 2010Should The Earth Be Cooling?
Re: Baz (25)"Anyway, we ARE cooling."
By ignoring the 20th & 21st Century temperature rise, you're still wrong. Anyway, this would have been a better version of that graph to use:As the other commentators point out, you're not using the correct resolution of time-frame for this thread. The Yooper
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Rob Honeycutt at 05:42 AM on 18 September 2010Should The Earth Be Cooling?
Baz... Are you missing the point of that chart? Yes, the overall natural trend should be a very slow (geologic scale) cooling. But that chart makes a hard break to the positive trend around the industrial revolution. You are doing exactly what Barry @ 19 pointed out. You skip from way too short of a trend to prove a point (5 or 10 years) to way to long of a trend (8000 years). The entire issue is about current warming and statistically significant trends. I think I understand where the focus on short term trends comes from though. What if, for some reason not yet understood, climate is taking a turn toward cooling? Do we need to wait for 30 years to find out? I'm sure someone here can answer this better than I can but I believe statistically you can see that turn in temps without waiting 30 years. You'd be looking to see if the temps start falling outside the 2 standard deviation boundaries of the trend. Alden Griffith does a really good job of addressing this whole idea of current cooling here. -
michael sweet at 05:38 AM on 18 September 2010What's happening to glaciers globally?
Everyone on this thread should know that mspelto is a researcher on glaciers. I appreciate his comments as they are more informed than what the rest of us can come up with. Thanks mspelto for your help. I was amazed at your web site on ice worms, I had thought they were fictional. -
michael sweet at 05:27 AM on 18 September 2010Should The Earth Be Cooling?
Baz, I noticed in your graph that 2004 is hotter than any other year on the graph. 2010 would be higher again. The warming has overtaken the cooling and it is now hotter than the previous 8,000 years: your data shows that!! You give a prefect example of what the post states. It is too bad when sceptics point us to data that proves themselves wrong. Unfortunately they can't read their own graphs. -
Albatross at 05:25 AM on 18 September 2010Should The Earth Be Cooling?
Baz, "Anyway, we ARE cooling." Over which window of time and for how long has this "global cooling" period been occurring Baz? Are you referring to the Fig. you linked to? If so, look at the insert in the Fig. in the link that you just posted...see that arrow in the top RHS, or the arrow at 2004? The long-term trend (20-30 yrs)in global temperatures is most definitely positive, only those in complete denial about what is happening think that the planet is not warming.Regardless, you are taking us off topic (ably assisted by me)-- this post/thread is on the last 30 years, not the last 10 000 years.
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Daniel Bailey at 05:24 AM on 18 September 2010Should The Earth Be Cooling?
Re: Baz (26) Try this, replacing the asterisks with < and > on the outsides of the text: *img width="450" src="http://upload.wikimedia.org/wikipedia/commons/c/ca/Holocene_Temperature_Variations.png"* Should work. The Yooper -
Should The Earth Be Cooling?
John, sorry for breaking your web design - stay happy. -
Should The Earth Be Cooling?
Soory, that didn't work http://upload.wikimedia.org/wikipedia/commons/c/ca/Holocene_Temperature_Variations.png -
Should The Earth Be Cooling?
So, the warming is masking the cooling? Where have I heard that before? Anyway, we ARE cooling. -
The contradictory nature of global warming skepticism
Who's going to point it out to archiesteel? -
The contradictory nature of global warming skepticism
Rob 246. As I understand it Grace reports an annual loss of 190 GT (+-77). As the Antarctic has 20,000,000 GT of ice then that 0.001% of ice is well within Grace's normal error, surely? If the Antarctic were gaining 190 GT of ice (according to Grace) then I'd say it wasn't gaining it! For me, it appears that the Antarctic is extraordinarily stable. As for the other end, as I said, we've been here before (just 70 years ago) but we never had television news crews to show how thin the ice was then. I'm not alarmed about the Arctic. Let's see what happens over the next few years. Thanks. -
mspelto at 04:51 AM on 18 September 2010What's happening to glaciers globally?
HR Fig. 1 is the best representation of global glacier records we have and it correctly shows that mass losses are much greater recently than during the 1945-1955 period you mentioned. Before 1945 we have no mass balance records. The first mass balance programs began in 1946, and these records are much more negative now for the specific glaciers examined then before. Cogley has done a better job than the IPCC graph. Further as a glacier retreats which many have, it is getting rid of it worst performing sections, which is supposed to increase its balance and return it to equilibrium. This has not happened even with retreat, mass balances are getting more not less negative. In some cases this is a sign of disequilibrium where the glacier will melt away. And two that I have measured mass balance on have. -
The contradictory nature of global warming skepticism
Paul Daniel Ash 249. Actually, as I clearly said, there was only one question in 177, and I answered it. As for 'response', no, not really, unless you actually want to debate the whole issue of AGW, satellite data, and OHC! Surely to 'respond' would just open up a massive debate which is surely best served item by item on threads as they come up. All the best. -
archiesteel at 04:26 AM on 18 September 2010The contradictory nature of global warming skepticism
@johnd: "a solution cannot become more acidic from being alkaline without becoming neutral first" True, but we're not talking about a solution here, but the ocean. The fact is there is more carbonic acid in the oceans due to dissolved CO2. Therefore, there is more acid in the ocean, i.e. it is becoming more acidic. -
archiesteel at 04:09 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
I think it's clear thingadonta is a "hit and run" troll. He barges it to post his half-baked anti-science drivel, then runs off, never responding to counter-arguments. Isn't this ground enough for bannination? -
dsleaton at 03:56 AM on 18 September 2010Human CO2 is a tiny % of CO2 emissions
Skepticalenergyguy-- Yes, CO2 has been higher in the past; yes, global temps have been higher in the past; yes, there are natural cycles that modify the Earth's climate. Modern humans, however, have never had to deal with a relatively very rapid global temperature increase. Our tripled population rests on an infrastructure and political/economic framework that has enjoyed a relatively stable climate. Worse yet, as this incredibly energetic economic mode has developed over the past 150-200 years, absolutely no responsibility was built into the system. Externalizing waste costs has been a matter of course for most of industrialized history, to the extent that when such externalization is pointed out, industrialists like, I assume, yourself are shocked by the gall of someone questioning the integrity of the system ("it's just CO2 -- we've been pumping it out for decades. So what?"). You can't seriously expect a rapid doubling of a gas that re-radiates long-wave radiation to have no effect, can you? You do understand how the process works, yes? Maybe that's the first question skeptics should be asked: how does global warming work, according to climatologists? Well, ESG? -
actually thoughtful at 03:40 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
So what is the correct (estimated date)? What is the correct (estimated) number of people affected by the loss of the glaciers? Are we fresh out of new science, to be going back over this very well-worked ground? -
Human CO2 is a tiny % of CO2 emissions
People who have convincing evidence and intellectually sound reasoning on their side don't generally have to accuse their rhetorical opponents of advocating genocide. Care to try again? -
Riccardo at 03:34 AM on 18 September 2010What's happening to glaciers globally?
HumanityRules I doubt anyone will find difficult "to aknowledge that mass balance loss was as fast in 1945-1955 as it was in the past decade". Indeed, is a good confirmation that the planet is warming, as it has in the first part of the last century and as anyone should aknowledge. Your skeptic mates, at least the followers of the mantra "it's not warming" or "surface temperature datasets are bogus", would be in trouble instead. -
Riccardo at 03:12 AM on 18 September 2010Human CO2 is a tiny % of CO2 emissions
I'd invite not to point to birth control (let alone genocide) just to frighten people with unacceptable theories never backed (and not allowed on SkS) by anyone here. -
muoncounter at 03:03 AM on 18 September 2010Human CO2 is a tiny % of CO2 emissions
#64: "The earth has naturaly cycled through significant temperature changes " Ah, the natural cycles game ... its all happened before. Dealt with extensively here and here and here. Its necessary to substantiate your claims. Please find a reputable source that documents a prior natural cycle with all of the following: increasing global temperatures, accelerating Arctic ice melt, etc (full list here); in the face of decreasing solar output, lower concentrations of atmospheric aerosols, etc (full list here); AND increased CO2, all over a very short period of time. And stop throwing around things like 'global birth control'. Once you come to understand that we have indeed made significant impacts on the environment, look for some practical ideas for creating change. -
Climate change: Water vapor makes for a wet argument
johnd - I am sadly beginning to feel that you are being deliberately obtuse on this thread. You can certainly feel back-radiation and it's effects. Go outside on a warm night, turn your face to the sky. Then, for comparison, go inside to your kitchen, open the freezer, and face that from a foot away (outside the downdraft). You will feel the difference! I tend to use the back of my hand for this - for some reason I find that's pretty sensitive to thermal radiation, and I can even to some extent navigate in the dark - picking out doorways and cooler windows directionally, even though the air temperature doesn't change based on orientation of my hand. The temperature at any location is the sum of all the inputs - conduction from the ground, back-radiation from the sky, etc. As to CO2 distribution - there are certainly +/- 1 to 2% regional variations, as shown here:But given the rates of diffusion of gases, that's not going to have a distribution effect over a few meters - it takes kilometers of distance to induce a diffusion time delay. The first meter of air will not have a different concentration of CO2 than the next 2-3 meters unless you're playing with a CO2 fire extinguisher. Water vapor, due to it's state changes and extreme temperature sensitivity (and the fact that it adjusts to local conditions over hours or days, not centuries like CO2) is much more varied in distribution. Think 'clouds'. Enough said here. Johnd - the effect you had issues with (cold ground air) is what's behind radiation fog; there is no mystery there whatsoever. Look it up. Your issues on this thread have become more and more murky, to the extent that I (and perhaps others) can no longer tell what you are concerned about. The core of this thread is that water vapor is a powerful greenhouse gas with a short time constant - evaporating or condensing very quickly due to local temperature changes. This makes water vapor primarily a feedback, not a forcing, as other factors such as CO2 are much more long-term; water vapor adapts to and amplifies those relatively fixed factors. End of discussion for me, johnd.
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Albatross at 02:42 AM on 18 September 2010Should The Earth Be Cooling?
Ned and Rob, Thanks for the great posts. Research has found that global SAT anomalies are best correlated with El Nino/La Nina indices when they lagged said indices by about 5-6 months. Specifically, "Christy and McNider [1994] and Angell [2000] show that the entire troposphere warms up with an overall lag of 5 to 6 months, but the lag is slightly less in the tropics and greater at higher latitudes." (from here) . DeepClimate undertook an analysis and identifed a 6-moth shift. So the marked impact on global SATs from the current (and quite strong) La Nina should be felt in the next two to three months. -
Skepticalenergyguy at 02:34 AM on 18 September 2010Human CO2 is a tiny % of CO2 emissions
Who is going to replace CO2 with H2S or HCN? That can't and won't happen. CO2 is not poisonious and naturally occurs with our existence. So the population of the world has almost tripled in the past 50 years which will of course increase the CO2 emitted into the atmosphere. What's the solution, global birth control? Genocide? The earth has naturaly cycled through significant temperature changes throughout it's creation. Does our data from the last 200 years really tell us that our incremental affect of CO2 is causing the global warming, or like I said previously, this is a natural cycle of the planet? -
HumanityRules at 02:32 AM on 18 September 2010What's happening to glaciers globally?
It does appear that Fig1 is a bit of a dud if you're looking for an accurate representation of global glacier records. UNEP/WGMS put out a joint report (http://www.grid.unep.ch/glaciers/) that has a global graph (Chap 5, Fig 5.9). You could use that. The problem is you have to acknowledge that mass balance loss was as fast in 1945-1955 as it was in the past decade. The final sentance needs to be amended if you want to represent the true picture. I suggest it ends ".....which has returned to the 1940's rate". Looking at Fig 5.1 suggests to me that any data going back beyond 1940 is really only a European (and to a lesser extent US) record. -
Albatross at 02:30 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
Barry @7, You just beat me to it! There is now a version 4.1 of the same incredibly informative talk available here is to vers. 4.1, but I see that there is now a version 4.2 out. -
muoncounter at 02:24 AM on 18 September 2010Should The Earth Be Cooling?
#22: Your graph puts these brief 'coolings' into perspective as the short-term noise superimposed on a long term cycle. That's a pretty basic concept in signal or time series analysis. I suppose a denier would look at the seasonal decrease in monthly atmospheric CO2 and conclude that there is a downwards trend: for 5 months out of 12, CO2 concentration is decreasing. Problem solved! Yet the peak and the average each year go up. Same picture: short-term variation superimposed on a long-term increase. Yooper had it exactly correct: The trend's the thing. -
michael sweet at 02:17 AM on 18 September 2010Video update on Arctic sea ice in 2010
I find it astonishing that people with no arctic experience would challenge the observations of an expert like Dr. Barber. If he says that the ice was expected to be thicker, that is what was expected. It is an extraordinary claim to suggest that Dr. Barber is wrong and data needs to be provided to support the claim, not just "I doubt it". He did not provide the background information because the talk was to experienced ice scientists who know the background information. -
Daniel Bailey at 02:15 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
Re: thingadonta (8) Got a source for your apparent quote? Or did you just make that up? The Yooper -
thingadonta at 02:07 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
"the likelihood of global warming disappearing by 2035 and perhaps sooner is very high if the earth keeps stabilising at the present rate". -
Rob Honeycutt at 02:07 AM on 18 September 2010Should The Earth Be Cooling?
Here is another chart that I did. Without even trying very hard I identified 5 different points where "CO2GHG theory has been in trouble." It's actually pretty easy to pick out sharp declines over short time periods. And, it seems to get a little harder to identify sharp declines as you move forward in time. -
Should The Earth Be Cooling?
Rob Honeycutt writes: we're winding down the hottest year in the temperature record, in a negative PDO, during a solar minimum and in a La Nina. Agreed 100% on the rest of your post, but the "in a La Nina" bit is somewhat confusing since we started out the year in a (moderate) El Nino cycle and temperatures typically lag ENSO slightly IIRC. My guess is that now that La Nina conditions have returned we'll see temperatures drop a bit from the highs of recent months. Nonetheless, Rob's main points are right -- KL's selection of 2002 is obvious cherry-picking, and his claim that this means "trouble" for AGW is just nonsense. -
Albatross at 01:56 AM on 18 September 2010Should The Earth Be Cooling?
Regarding oceanic heat content. (OHC). From Palmer et l. (2010; "State of the climate in 2009" report): "Even so, errors are too large to obtain reliable trends over a few years. However, the three curves all agree on a significant decadal warming of the upper ocean since 1993, accounting for a large portion of the global energy imbalance over this time period (Trenberth 2009), and the three sets of maps (not shown) from which the curves are produced show similar largescale features." For the same period covered in the above graphs (from 1979 onwards)0-700 OHC has increased by about 10x10^22 J [From Fig. 3.9 in the "State of the climate report"] That said, their Fig. 3.8 gives a different picture, so I am not entirely sure which one to trust. -
barry1487 at 01:48 AM on 18 September 2010Should The Earth Be Cooling?
You also have to believe that everything else should stop happening under CO2 warming. Skeptics don't believe in interannual variability, which is why they conflate short-term weather phenomena and climate. No, it has to be monotonically warming, year-by-year, or there's a 'problem with AGW'. Ask a skeptic what the minimum period is to get a bead on climate and they'll say nothing, or that 30 years is wa-a-y too short. It's like asking them when the Medieval Warm Period was supposed to have occurred. Makes them silent or uncomfortable. -
barry1487 at 01:40 AM on 18 September 2010Himalayan Glaciers: Wrong Date, Right Message
It might be worth pointing out that rhe mistake wasn't spotted by some steely-eyed skeptic auditor, but by one of the IPCC AR4 authors, J. Graham Cogley. List of AR4 authors J. Graham Cogley's view on the mistake:This was a bad error. It was a really bad paragraph, and poses a legitimate question about how to improve IPCC’s review process. It was not a conspiracy. The error does not compromise the IPCC Fourth Assessment, which for the most part was well reviewed and is highly accurate.
http://web.hwr.arizona.edu/~gleonard/2009Dec-FallAGU-Soot-PressConference-Backgrounder-Kargel.pdf [p. 74] Cogley backs the IPCC AR4, despite this error. -
Rob Honeycutt at 01:38 AM on 18 September 2010Should The Earth Be Cooling?
Ken Lambert@14... "Just the fact that we are all niggling about whether the Earth is slightly heating or cooling over the last 8-15 years, or whether it is statistically significant is pretty good proof that the theory of CO2GHG forcing as the main driver of global warming is in serious trouble." That statement makes absolutely no sense to me at all. By that logic the "theory of CO2GHG forcing" would have been "in trouble" several times over the past 50 years. Look at the temperature record and plot out all the 8 and ten year trends. I just got on the Wood for Trees site and started imputing dates. You literally have to go through each possible year to present and pick out 2002 to get the lowest trend. That is by definition cherry picking. Here are the results of those searches...Not only that, but to claim that CO2GHG theory is in trouble you have to completely ignore the fact that we're winding down the hottest year in the temperature record, in a negative PDO, during a solar minimum and in a La Nina.
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Should The Earth Be Cooling?
mdenison makes good points about the longer term (millennial or longer) cooling trend. Wanner et al. 2008 provides a nice overview of climate change from the mid-Holocene to the start of the industrial era. There was a long, slow cooling trend in NH summers, due to orbital geometry, plus more spatially complex changes in humidity, winds, and temperatures elsewhere. Read the paper for all the details, but the following figure from the paper (click to enlarge) provides a nice overview.Figure 18 from Wanner et al. 2008. Spatial synthesis: global climate change for the preindustrial period (AD ~1700) compared to the Mid Holocene (~6000 cal years BP). People refer to the Mid-Holocene as a "warm period" (I just did in a comment in another thread!) so it's tempting to guess that you could just invert all those changes and get a pretty good idea of where we're headed, warming-wise. But unfortunately that won't work, since the change from Mid-Holocene to modern conditions was driven by orbital geometry, which involves changing the spatial-seasonal distribution of solar irradiance, rather different from the spatial-seasonal distribution of warming caused by increased CO2.
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What's happening to glaciers globally?
BP, obviously the Holocene Thermal Maximum was a warm period particularly in the mid- to high-latitude Northern Hemisphere, thanks to Milankovich geometry. That obviously doesn't apply to current conditions. Of course, if we haven't already done so we'll certainly be exceeding HTM temperatures soon enough, then exceeding MIS-5e (Eemian) temperatures as well. That doesn't bode well for glaciers. It seems unlikely that the present rapid retreat will be reversing itself any time soon.
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