Comments on: The Polar Slush Cap?

The Polar Slush Cap?

[expletive deleted] — Fri, 07 Sep 2007 13:21:19 -0800

"In an average August between 1979 and 2000, the Arctic Ocean was covered with about 3 million square miles of sea ice, according to the National Snow and Ice Data Center. By Labor Day this year, the total had shrunk to a little more than half that, shattering the previous record low set in 2005."

By: mullingitover

mullingitover — Fri, 07 Sep 2007 13:24:38 -0800

So this means that more ocean is exposed, which means more evaporation, more precipitation, and more snow. Or is the planet not homeostatic like that?

By: The Card Cheat

The Card Cheat — Fri, 07 Sep 2007 13:27:37 -0800

It means, to steal a line from Jon Stewart, that our kids will have to call Iceland Land.

By: kuujjuarapik

kuujjuarapik — Fri, 07 Sep 2007 13:28:16 -0800

More precipitation does not necessarily mean more snow.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 13:28:39 -0800

By: Kirth Gerson

Kirth Gerson — Fri, 07 Sep 2007 13:30:32 -0800

But Greenland may finally make sense.

By: psmealey

psmealey — Fri, 07 Sep 2007 13:31:07 -0800

How can I help? I have ice cube trays at the ready.

By: Burhanistan

Burhanistan — Fri, 07 Sep 2007 13:33:04 -0800

No wonder the ultra-rich are so interested in space travel.

By: mek

mek — Fri, 07 Sep 2007 13:33:26 -0800

As sea ice melts, thawing accelerates, as the sea is much darker than ice, and therefore absorbs much more sunlight. This year's arctic thawing breaks the old record by about 25%, as in, 25% less ice in the Arctic than ever before. We're on pace for a complete seasonal thaw in the Arctic in a decade or two... which will bring all sorts of new oil reserves online, huzzah!

By: absalom

absalom — Fri, 07 Sep 2007 13:38:07 -0800

mullingitover: Less sunlight due to global dimming actually means less evaporation. There was a Nova about it this week.

By: Burhanistan

Burhanistan — Fri, 07 Sep 2007 13:39:31 -0800

I am an expert on this subject because I have a heartfelt conviction and/or I saw something with CGI diagrams.

By: stenseng

stenseng — Fri, 07 Sep 2007 13:43:37 -0800

"As sea ice melts, thawing accelerates, as the sea is much darker than ice, and therefore absorbs much more sunlight." I have the perfect solution! Let's cover the arctic in all those foam packing peanuts we need to get rid of! They're pretty reflecty!

By: localroger

localroger — Fri, 07 Sep 2007 13:43:49 -0800

Every year we learn that this ice is melting in new and fascinating ways that we never suspected were possible the year before. I'm starting to think it will be all gone by 2015. Very soon there won't be any multi-year ice left, and the ocean will absorb too much heat during the summer to let it build up again for ever and ever amen. Sucks to be a polar bear.

By: kuujjuarapik

kuujjuarapik — Fri, 07 Sep 2007 13:47:10 -0800

stenseng- we're working on it.

By: mullingitover

mullingitover — Fri, 07 Sep 2007 13:47:37 -0800

mek writes "As sea ice melts, thawing accelerates, as the sea is much darker than ice, and therefore absorbs much more sunlight." Keep going! It absorbs more sunlight, therefore gets warmer, and therefore evaporates, therefore it's more likely to fall as snow. Don't worry. At some point in the future, I promise you, the planet is going to be locked in ice again (or perhaps a mile-wide meteor will strike, or perhaps a supervolcano will blow up. Or perhaps a trifecta!). Just because the current trend is away from that state doesn't mean that it's going to be like that forever.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 13:48:37 -0800

Mullingitover, the question of feedbacks, and what the magnitudes of positive and negative feedbacks would be is unquestionably the hardest challenge faced by climate modelling. Any explanation as terse as yours would be an oversimplification, but this is likely to be at least one of the consequences. What we are witnessing is a tipping point from a pseudocontinental climate in the arctic basin to a marine one, which will have many enormous impacts on the climate of the entire northern hemisphere. One feedback that is widely agreed to be the strongest though, is the loss of albedo. As the ice melts, it exposes open water. Ice reflects 90% of incident light into space. Water, on the other hand, only reflects 10%. Most models agree that this effect will be by far the dominant feedback in the arctic, and is the primary reason why the arctic is expected to warm so much faster than the rest of the world. Observation is now confirming this prediction. What is worrying scientists is how much faster this is happening than they thought. The sea ice minimum today is where the IPCC thought it would be in 2050 just last winter.

By: Burhanistan

Burhanistan — Fri, 07 Sep 2007 13:49:11 -0800

Don't worry. At some point in the future, I promise you, the planet is going to be locked in ice again Kind of like, why should I finish this project when the sun is just going to swell up and swallow the interior planets someday?

By: mrnutty

mrnutty — Fri, 07 Sep 2007 13:50:08 -0800

This seems like a good time to link to one of my favorite comments by DU

By: ninjew

ninjew — Fri, 07 Sep 2007 13:55:57 -0800

So, I mean what happens now? Do I stock up on canned food and shotgun shells and wait for the zombies?

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 14:00:48 -0800

Sorry, I should correct that last comment. According to this graph, the mean of the IPCC models published earlier this year predict the sea ice minimum to reach 4.4 million km² around 2040 or so. So we are about 30 years ahead of the mean of models. As you can see from the graph, the most pessimistic of these models, which underestimates the observed ice from the past by about 20%, oredicted that the ice would retreat as far as it has this summer by about 2025.

By: hexxed

hexxed — Fri, 07 Sep 2007 14:01:47 -0800

We really can't stop it now, so I guess we just have to live the experiment.

By: kuujjuarapik

kuujjuarapik — Fri, 07 Sep 2007 14:01:52 -0800

Nope, no zombies. But you could start a lucrative career as an Inuit lifeguard.

By: mullingitover

mullingitover — Fri, 07 Sep 2007 14:02:22 -0800

Burhanistan writes "Kind of like, why should I finish this project when the sun is just going to swell up and swallow the interior planets someday?" Close, but in terms of scale the next ice age would be coming in a couple weeks whereas the collapse of the sun would be decades away. Or something. Regardless, in that scale we'll all be dead in a few seconds at best.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 14:02:49 -0800

Well, now I see mullingitover isn't interested in actually discussing this, just making assertions for the sake of being contrary.

By: Floydd

Floydd — Fri, 07 Sep 2007 14:05:55 -0800

Have they ruled out terrorism yet?

By: Smedleyman

Smedleyman — Fri, 07 Sep 2007 14:12:20 -0800

Clearly what's needed is billions of gallons of Wild Blue Cherry syrup and a big straw. We can give the world a brain freeze. And of course, sphenopalatine ganglioneuralgia kills zombies (you gotta attack the brain). Simple. ...oh, the warming right. Albedo, yeah. Uh...gimme a minute.

By: mullingitover

mullingitover — Fri, 07 Sep 2007 14:17:03 -0800

[expletive deleted] writes "Well, now I see mullingitover isn't interested in actually discussing this, just making assertions for the sake of being contrary." What's to discuss? The arctic ice pack is disappearing rapidly. You're preaching to the choir, I don't dispute this in the least. What are we going to do about it? Get out our freezers and start making ice cubes to send to the arctic? Humanity is in a deadly embrace with oil. At this point, every person reading this thread is burning calories that come indirectly from fossil fuels. The side effect of this is that we're fucking with the composition of the atmosphere. This could very well be the cause of the retreating ice pack. My only assertion that perhaps doesn't resonate well in the echo chamber is the significance of humanity on the planet. In geologic terms, we're a flash in the pan, and soon enough (unless we accomplish the seemingly unlikely feat of becoming a spacefaring species) we'll be history, ground up under the weight of endless glaciers. Climate change will suck. I agree. A lot of people will lose their nice things. Many will die. However, it's not going to be the end of humanity (we're like rats, tough and scrappy) and certainly not going to be the end of the world.

By: mek

mek — Fri, 07 Sep 2007 14:19:21 -0800

Keep going! It absorbs more sunlight, therefore gets warmer, and therefore evaporates, therefore it's more likely to fall as ~~snow.~~ precipitation. Now you're on the trolley. It's certainly possible that global warming will trigger some sort of backlash which will throw us into another ice age (it's actually much less unlikely than it sounds) but I mean, extreme hot or extreme cold - either way it's going to suck.

By: stbalbach

stbalbach — Fri, 07 Sep 2007 14:38:23 -0800

the significance of humanity on the planet. mullingitover, anyone who questions that does not resonate well with the rest of humanity.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 14:43:35 -0800

Mullingitover, I apologise, that was a bit of a kneejerk response on my part; global warming has a tendency to bring out the trolls. I see where you are coming from, but an ice age soon is probably unlikely. See this S^b post. While more work certainly needs to be done, the current research suggests that the ocean is almost at its capacity to absorb CO₂. This will mean that even if we manage to stabilize levels of GHGs at say, 175% of pre industrial levels--which looks increasingly optimistic--the earth will be kept in an interglacial for at least a few hundred thousand years.

By: nasreddin

nasreddin — Fri, 07 Sep 2007 15:02:45 -0800

I mean, extreme hot or extreme cold - either way it's going to suck.

Some say the world will end in fire, Some say in ice. From what I've tasted of desire I hold with those who favor fire. But if it had to perish twice, I think I know enough of hate To know that for destruction ice Is also great And would suffice.

- Robert Frost, 1920

By: Avenger

Avenger — Fri, 07 Sep 2007 15:05:23 -0800

why do climatologists hate America? No worries anyway, Jesus is coming back soon. *smiles, waits for apocalypse*

By: Hairy Lobster

Hairy Lobster — Fri, 07 Sep 2007 15:15:38 -0800

mekKeep going! It absorbs more sunlight, therefore gets warmer, and therefore evaporates, therefore it's more likely to fall as ~~snow~~. precipitation. From what I recall some of the current models seem to indicate that both ocean water evaporation and precipitation will likely increase because of the effects of global warming. However, the same models unfortunately predict a growing shift of said precipitation away from dry land out to the open sea leading to an increase of droughts and to an accelerated depletion of fresh water sources.

By: barchan

barchan — Fri, 07 Sep 2007 15:40:06 -0800

There are a couple of things that bother me about these data. While I 100% acknowledge the downward trend, we only have 30 years of data. Do we know enough to call this statistically relevant (especially with the recent news about global temperature data being affected by the Y2K bug)? Secondly, there seem to be 5-7 year cycles where, starting with a dip and ending with a dip, you have two peaks within. What's causing that? I've never met anyone who could explain that in a satisfactory way. Third, why does the sea ice always seem to melt from the west (towards Alaska) but remain mostly the same from the east (towards Greenland). Anyone interested in the oceanic conveyor belt should take a look at that, but I haven't seen any research. And lastly but in a crackpot kind of way, even though there is no correlation between the geographic tilt and the magnetic poles, I've always wanted to see Arctic sea ice volume compared to the wanderings of the magnetic North Pole.

By: psmealey

psmealey — Fri, 07 Sep 2007 15:51:00 -0800

Robert Frost had no way of knowing how eponysterical he actually was.

By: eriko

eriko — Fri, 07 Sep 2007 15:55:26 -0800

There are a couple of things that bother me about these data. While I 100% acknowledge the downward trend, we only have 30 years of data. We have *vastly* more than thirty years of data that the artic ice caps was present and large. Explorers spent centuries tying to make the Northwest Passage (a trip not accomplished until 1906). See, for example, Henry Hudson in the very early 1600s. We have a very good idea on the ice pack size over the last few hundred years.

By: quin

quin — Fri, 07 Sep 2007 15:58:56 -0800

mullingitover : (we're like rats, tough and scrappy) I actually find humans to be more chewey than scrappy. But a bit of tenderizing and some A1 sauce, and you really stop noticing.

By: elpapacito

elpapacito — Fri, 07 Sep 2007 16:08:48 -0800

[expletive deleted] writes "The sea ice minimum today is where the IPCC thought it would be in 2050 just last winter." That's both good news, because it implies the extimates were off 40 years questioning the reliability of the same catastrophic models, and maybe bad news because the scale of that event seems enormous to me , unlikely to cause negligible effects. My very simplistic reasoning is that if some catastrophic events such as the greatest explosion of volcanoes had some atmospheric effect , then the liquefaction of such an enormous mass of water maybe is going to have some atmospheric effect as well ; that regardless of the cause (co2 increase , something else, combination of multiple factors). Yet I understand that my knowledge about the scales and proportions is insufficient, as we are talking about millions tons. I have quite some troubles wrapping my mind around the idea the estimate for earth's weight is 5.9736×10^24 kg or 5.9736 x 10000000000000000000000000 kgs !

By: elpapacito

elpapacito — Fri, 07 Sep 2007 16:16:18 -0800

emh sorry the earth's mass !

By: barchan

barchan — Fri, 07 Sep 2007 16:23:02 -0800

But where? If you know where, I'd love to see it. (I'm very curious, not being contrarian. ) I too have heard of this data but I've never seen it scientifically presented. I've found things like this which includes temperature. And there are problems with this data in the link that suggests it may even be warmer. And while maybe we don't have actually data points, but surely someone has made a sea ice map based on explorers' old reports. It would be awesome to see something like that. I also know the Russians did some work since the 1900's, but there have been various issues with the accuracy of their data and measuring techniques, etc. And what I found particularly interesting is sea ice volumes in the Antarctic took a dip in the 80's but (at least until 2005, but 2000 in this chart) are slowly increasing.

By: nasreddin

nasreddin — Fri, 07 Sep 2007 16:27:28 -0800

And what I found particularly interesting is sea ice volumes in the Antarctic took a dip in the 80's but (at least until 2005, but 2000 in this chart) are slowly increasing. Do you think this could be because of continental ice from Antarctica melting partially and breaking off? Just speculating.

By: barchan

barchan — Fri, 07 Sep 2007 16:42:00 -0800

True continental ice from Antarctica (the Western and Eastern ice sheets) are protected (for the most part) by ice shelves (sea ice). Ice shelves break off (like the Ross Shelf). But I don't see how that would affect it, since that is an annual thing (although it is affected by global warming now). If the ice sheets start melting we be in BIGGG trouble.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 16:53:45 -0800

Eriko makes a good point. If the sea ice extent today was the same as when Franklin set out to find the Northwest Passage, he would have sailed clean through it without encountering any ice at all. He would have made it all the way to China. Instead, his ships were bound up in ice, never to sail again, hundreds of miles south of a passage that has been completely free of even trivial amounts of ice for over a month.

By: hal9k

hal9k — Fri, 07 Sep 2007 16:58:47 -0800

Try to maintain a positive latitude They say the polar ice is contracting So I will too: That's n'ice

By: barchan

barchan — Fri, 07 Sep 2007 17:01:10 -0800

Yes, but that could easily be explained by seasonal variation; for example, between 1995 and 1996 alone there was a 2.0 million sq. km difference. There are famous pictures of American subs actually surfacing in open water at the pole in 1985 but unable to break the surface except with their conning tower in 1995.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 17:02:10 -0800

This animation is interesting. It shows how old sea ice is steadily dissapearing. New ice is thinner and melts faster than old ice.

By: barchan

barchan — Fri, 07 Sep 2007 17:09:04 -0800

That is interesting. What's the scale on the side, sir? Km?

By: barchan

barchan — Fri, 07 Sep 2007 17:13:32 -0800

Ah! From the site of the animation, "but changing winds that have transported fairly thick ice out of the Arctic Ocean into the North Atlantic, and decreased the length of time that ice is "sequestered" in the Arctic Ocean where it might have a chance to grow thicker." This might explain why the ice melts more towards the west!

By: AppleSeed

AppleSeed — Fri, 07 Sep 2007 17:22:56 -0800

14,000 years of ice core data Issac Asimov wrote a wonderful book called A Choice of Catastophes, in which he breaks disasters down into localized disruptions, civilization enders, life enders, world enders, and Universe enders. For each, he offers some way out (with plausibility varying along with likelihood and severity of the disaster in question). There often seems to be some confusion about which level of disaster Global Warming is shaping up to be. If this is in fact the Runaway Greenhouse Effect, we're talkin' civilization ender. Mass extinction is already underway. The time horizon approaches what appears to be unthinkable to many: this lifetime. Now. Amazon link: http://tinyurl.com/yod3v6 I'm relatively new here, but I suppose I need to mention the Global Warming web site was done by a co-worker (it's a non-profit, free, academic site).

By: The World Famous

The World Famous — Fri, 07 Sep 2007 17:23:05 -0800

Learn to swim, coastal dwellers. Oh, right, that's me. Drat.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 17:29:00 -0800

Barchan, while seasonal variation can be quite large, there is an unmistakeable 30 year downward trend that is accelerating like the models predict, but much faster.

By: Pinback

Pinback — Fri, 07 Sep 2007 17:29:32 -0800

Kirth Gerson: But Greenland may finally make sense. It already does. "Temperatures in Greenland have risen by two degrees over the past decade ... allowing farmers to grow new crops and raise cattle, for the first time since the Vikings."

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 17:34:04 -0800

Barchan, the scale top right is age of ice in years. The dark blue is seasonal ice. The bottom left shows the year. A comment on a friends blog noted that this animation made her think of a dying heart.

By: Ethereal Bligh

Ethereal Bligh — Fri, 07 Sep 2007 17:45:23 -0800

"I'm starting to think it will be all gone by 2015." That's a bit early, but 2015 will be lowest low of the ~seven year cycle that is also true of this year. So, it should be about that long until we see something (much) worse than we've seen this year. For the next few years, it should be getting better.

By: barchan

barchan — Fri, 07 Sep 2007 17:49:26 -0800

ED, you'll notice in my first comment I explicitly acknowledge the 30 year downward trend. :) I have no argument about the recent trend, but whether or not it is statistically relevant. A basic statistics class teaches you that "30" is just minimal in a sample size for relevance. I want to see real, scientific data prior to that, and I think that's a really simple thing to ask for. In the excellent ice core graph Appleseed gave us you can see the tremendous variation that earth cycles have. The basic questions is, are we in one of those variations/how much have we (as humans) affected the variation/can we return to "normal", and that requires tremendous amounts of data - way beyond 30 years, and that is just for sea ice alone, which is just one part of understanding the global system. Oh, and The World Famous, we don't have to worry about sea level rising due to Arctic ice caps melting due to their displacement of water; what melts doesn't change the volume of the ocean. If that makes you feel better. Of course, if other things melt...

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 18:24:17 -0800

Barchan, the main problem is that a serious estimation of sea ice extent wasn't really possible before satellite monitoring began in the late 70s. 30 years is as far back as the data will go. Any earlier and only anecdote remains. We can perhaps speculate about seasonal variation, but the fact remains that the northwest passage is completely free of ice this summer. Not even the Inuit claim to have seen anything like it before.

By: AppleSeed

AppleSeed — Fri, 07 Sep 2007 18:37:47 -0800

The plot of CO2 over 650,000 years should put to rest the questions: "are we in one of those variations/how much have we (as humans) affected the variation/can we return to 'normal'" 1) Yes. 2) Double the CO2 maxima over 650,000 years and many natural cycles prior to the industrial revolution. 3) Extrapolating the chart a mere 30 years crosses the tri-sigma point. My personal assessment, which isn't worth much beyond any layman's reading of a graph, is that we're toast. I think the interesting questions are - are Mars and or Venus examples of potential stable states of Earth? Because the CO2 record shows Earth systems recover equilibrium - within certain bounds. I hope well over half a million years constitutes "tremendous amounts of data". Another side point - I suspect a large portion of the population suffers innumeracy to the point they cannot read that plot (this is not aimed at anyone in this thread, just a speculation). If you can read it, I can't see how one could possibly think there's any doubt this is a very dire situation.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 18:42:09 -0800

Oh, and I saw that acknowledgement of the downward trend, but to be fair, you did question if it was statistically relevant. I'd say it's pretty damn relevant. The question this year is how far will summer ice extent deviate from the mean: 35% or 40%? The ice that was lost will be renewed this winter, for sure, but it will be thinner and easier to melt than the old ice that is already gone. Factor in that the huge open hole north of East Siberia and the Chukchi Sea has had a high pressure system over it most of the summer, and you have an ocean that will take longer than normal to refreeze. I hope the pessimists are wrong. I linked to a blog upthread that discussed papers predicting ice loss much faster than the models predicted. This was in May, when the melt was just begining and didn't seem out of the ordinary. Most of the comments were skeptical of the more pessimistic prediction, which was based on extraplolation from the existing data rather than the models. It is, of course, too early to be certain, but so far the pessimists have been proven right.

By: AppleSeed

AppleSeed — Fri, 07 Sep 2007 18:46:34 -0800

Speaking of not reading the plot correctly - I should have said 30 years to a doubling, not tripling. But still, we're right now way over the max of any of those four previous peaks, which were times when the ice caps receded. In Gore's Inconvenient Truth, he gets in a cherry picker to show where CO2 concentrations will be in 30 years. To me, that moment says it all.

By: five fresh fish

five fresh fish — Fri, 07 Sep 2007 19:23:36 -0800

Folks, I think we need to accept the idea that we've tipped the balancing rock. IMO it is going to turn out that the earth is bi-stable: it likes to be either ice-clad in glaciers, or hot and humid. The niche we've been occupying is only temporary unless we can figure out how to out-engineer the natural processes. What should really be freaking everyone out is the probability of the oceans reaching a high enough temperature to release the crystallized methane that covers large parts of the ocean floor. Or, alternatively, the release of methane from the arctic permafrost. One will set off the other, resulting in a massive release of gasses that are 3x worse wrt global warming. We are headed for dinosaur climates and it's going to be the end of our current civilization. It is going to happen within out lifetimes. We. Are. Fucked.

By: barchan

barchan — Fri, 07 Sep 2007 19:31:03 -0800

I guess I'm not making myself clear; you're thinking I'm "anti-global warming" or something along those lines. I'm one of those people contributing to that half a million years of data, and beyond, and I'm not talking about CO2 or global warming in this particular instance. I'm talking about the prior extent of sea ice and making a baseline from which we know what is normal and what isn't for sea ice, that is all. And this is an extremely complicated system. If you want to run true models, it's going to take a petraflop machine to even begin to take in all the variables. For example, that the wind is affecting sea ice thickness. I'm also aware that satellite monitoring only started in the 70's for both caps. But there has to be data out there prior to this. I can't see a modeler worth their salt claiming a trend is accelerating on such a poor sample size. At the risk of sounding obstinate, I'd like to see that data, and I'm wondering if someone has it. I think it would be interesting, not something to use as a weapon against anthropogenic effects. I also think that we've gotten a lot better at capturing this data, and I wonder how much that is affecting the trend. And for a true downward trend, you have to have a plateau or a high from which to start. I'd like to see evidence of that. I'm sure it's there somewhere, but where? Data I've seen are either on say, thousand year cycles, or, they're on a measly 30-50 year graph. I just want to see something that shows for sea ice, what's been going on recently - geologically speaking. That's all I stated. I didn't mean to start an argument. Ice caps wax and wane. They've been doing this for millions of years. If you look at this wonderful isotopic record chart of temperature and ice volume based off of a type of plankton called benthic forams, you will see this trend. (Explained by the man who pioneered this, Nick Shackleton, here.) We're also very much influenced by something called Milankovitch Cycles. 400,00 years ago, we underwent a major change in the eccentricity cycle. We're due for another change because it's a 400,000 year cycle. Orbital forcing also affects climate, and do we know right now, what orbital forcing is doing to us...no. So... I don't think we're toast just yet. Earth systems have a wonderful capacity for bouncing back. We've been very much warmer before - Cretaceous Thermal Maximum, Paleocene/Eocence Thermal Maximum, etc., and geologically speaking our contribution (so far) is minimal. Before we start messing with the system like tossing iron in the ocean to create more plankton to create more of a carbon sink, we need to understand the system as completely as possible. And to me, that starts with the simple things like explaining why a 30 year old graph is relevant, and what data beyond that it is based on. Climate is geological time; 30 years is weather. I think both of you would be interested in a book called The Glacial World According to Wally. It's from the man who pioneered climate science and contributed, wow, the entire basis: Wallace S Broecker. It's a great book for understanding how earth systems work, and you can download the .pdf.

By: AppleSeed

AppleSeed — Fri, 07 Sep 2007 19:54:30 -0800

IPCC report was intentionally conservative. No one can predict the future with certainty, but there are sensible things we can do to mitigate the problem (where the problem is conducting an uncontrolled experiment on the biosphere). Add enough energy to five fish's bi-stable system, and it can fail to restore, which I think was the point about methane release.

By: Burhanistan

Burhanistan — Fri, 07 Sep 2007 19:55:47 -0800

I think people will still be arguing about this as the water starts seeping into their living rooms.

By: barchan

barchan — Fri, 07 Sep 2007 21:02:15 -0800

The clathrate gun hypothesis is an excellent example of panic based on not understanding the earth. We don't understand clathrate release yet. We have never satisfactorily documented a case of full clathrate release, although there are lots of hypotheses (such as at the PETM) causing mass extinctions and changing global climate. If the Permian extincition event did occur as a methane hydrate release it occurred in the middle of an ice age, for one, where it wasn't that hot. Other smaller but obvious warming events, particularly in the Paleogene with events likethe Elmo horizon would mean, if the clathrate hypothesis is correct, that methane release happened all the time. Obviously the system recovered if this happened in the past. If it didn't happen in the past, global temperatures were much much higher and didn't cause this to occur. We have not reached the tipping point. The tipping point would be melting of the continental ice sheets and causing the oceanic conveyor system of deep cold ocean bottom water (AABW) to cease working. Burhanistan hit it right on the nose. What we have reached is the point where we can either get off our asses and do something or just be apathetic. But out-engineering earth systems we don't understand would be the last thing we should try. The first thing we should try is outlawing fossil fuels. And that includes not only the U.S. but developing countries, where oil is not so much a problem but coal is. We have reached the end of the current civilization as we know it in that we need to change our ways. But that doesn't mean we can't adapt and thrive and become even better. (I say this as we sit here arguing this on our plastic computers (from oil) run by either natural gas or coal supplied electricity.)

By: localroger

localroger — Fri, 07 Sep 2007 21:05:52 -0800

*looks to see if the water is seeping into my living room* Not YET

By: five fresh fish

five fresh fish — Fri, 07 Sep 2007 22:00:39 -0800

Add enough energy to five fish's bi-stable system, and it can fail to restore, which I think was the point about methane release. The point about methane release is that it's going to tip us into one of the stable states. I think we happened to get really lucky this past few thousand years. The earth has, iirc, spent more time being damn cold and damn hot-n-muggy than it has a pleasant 28C with clear skies and a 30% chance of precipitation overnight. We're going to find out the earth swings violently between extremes, IMO. And, hey, aren't we also do for a magnetic pole change? Fun times, fun times!

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 22:03:25 -0800

Barchan, I agree that data about historical sea ice cover would be interesting, but where would it come from? I suppose I'm not convinced someone has it. You would certainly know better than me. If you can find it, I'm sure lots of people would be interested in it.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 22:04:16 -0800

Oh, and I would like to say I hope you continue to contribute to climate threads. I'm in the process of reading what you linked upthread.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 22:06:36 -0800

What we have reached is the point where we can either get off our asses and do something or just be apathetic. But out-engineering earth systems we don't understand would be the last thing we should try. The first thing we should try is outlawing fossil fuels. Bears repeating. That is all.

By: altman

altman — Fri, 07 Sep 2007 22:19:09 -0800

Climate change will suck. I agree. A lot of people will lose their nice things. Many will die. However, it's not going to be the end of humanity (we're like rats, tough and scrappy) and certainly not going to be the end of the world. while human caused GW may not be the end of the world or of humanity; (although that also remains an open question. what makes you think humans are any different from all those which have gone before?), it almost certainly does mean the end of civilization as we know it. and it is hard to see how that is a thing to be rushing, blindly and greedily, towards . as to what any individual can do to make an immediate difference. see my website, EuthanasiaClinic.com for details.

By: Burhanistan

Burhanistan — Fri, 07 Sep 2007 22:20:36 -0800

Yes, nihilism and fatalism is certainly better than trying to use our higher brain functions.

By: [expletive deleted]

[expletive deleted] — Fri, 07 Sep 2007 22:31:16 -0800

The best part of nihilism and fatalism is it makes the sacrificing our comfortable carbon lifestyles unnecessary and uncool.

By: sindark

sindark — Fri, 07 Sep 2007 23:21:29 -0800

The Greenland ice cap is melting so quickly that it is triggering earthquakes as pieces of ice several cubic kilometres in size break off.

By: barchan

barchan — Sat, 08 Sep 2007 08:19:56 -0800

Thanks for the good post, btw. And jolly good discussion! /shakes hands all around

By: AppleSeed

AppleSeed — Sat, 08 Sep 2007 09:27:10 -0800

NCAR has a little something on sea ice going back to 1870's ship records. I only skimmed it, but looks like what you're looking for. Also check out the nifty animations!

By: [expletive deleted]

[expletive deleted] — Sat, 08 Sep 2007 10:52:56 -0800

AppleSeed, that is a great find. Thanks. I am curious, however, why the data is digitized as a cylindrical projection. That seems like an odd choice for studying the arctic. Barchan, your profile says you are a micropaleontologist; I'm curious if your work involves examining the stable isotope ratios of forams? That has always struck me as one of the most ingenious methods of reconstructing past climates. The cleverness of you people I perhaps failed to consider when I doubted the existence of hard data on the original topic of this thread. I would love to see that data, and it's interpretation.

By: AppleSeed

AppleSeed — Sat, 08 Sep 2007 20:55:55 -0800

Expletive, why not e-mail the authors? I'd be surprised if they don't have polar projections of the data. Maybe it's helpful to see both poles and all latitudes simultaneously, depending what you're looking for?

By: lamarguerite

lamarguerite — Mon, 01 Oct 2007 09:19:51 -0800

Everyday similar data comes at us, we are being inundated with pictures of polar bears surrounded by water. Meanwhile, we sit in the safety of our homes, thousands of miles away, and we don't feel a thing. The threat is very real, but we are unable to experience its reality. There, lies a big part of the global warming challenge. To do with human psychology, and the way we are wired to react to situations that are an immediate threat to us, both in time and distance.