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July 25, 2012 9:48 AM   Subscribe

In the five day period between July 8th and July 12th, Greenland saw a dramatic and unprecedentedly rapid thawing across 97% of its surface ice cover. Initially, NASA and other experts questioned the satellite data, viewing such a rapid melting as too unlikely to be true, but NASA has since confirmed the results.

"'...a ridge or dome of warm air hovering over Greenland... coincided with the extreme melt... Each successive ridge has been stronger than the previous one,' Mote said in a NASA statement."
posted by saulgoodman (86 comments total) 13 users marked this as a favorite

 
There have been melts covering this much of Greenland's surface area before, notably, but so much melting in such a short period of time is what's really scary.
posted by saulgoodman at 9:49 AM on July 25, 2012


loss of 97% of its surface ice cover.
This should be clarified that it is "surface thawing", not complete and thorough loss.
posted by Jehan at 9:50 AM on July 25, 2012 [14 favorites]


Good point; that's what I was trying to express with "its surface ice." Or better yet, as the first article puts it below:
"Five days later, an estimated 97 percent of the surface area was thawing. Nearly the entire surface of the ice sheet, from the very edges to the very center, saw some thawing."
posted by saulgoodman at 9:52 AM on July 25, 2012


If you, like me, had a minor heart attack reading the headline, this should allow you to get on with your day (if not necessary your century):
"Ice cores from Summit show that melting events of this type occur about once every 150 years on average. With the last one happening in 1889, this event is right on time," says Lora Koenig, a Goddard glaciologist and a member of the research team analyzing the satellite data. "But if we continue to observe melting events like this in upcoming years, it will be worrisome."
posted by theodolite at 9:53 AM on July 25, 2012 [25 favorites]


I think your wording is slightly inaccurate -- I don't think it lost its ice cover, but rather that the very top of the (extremely thick) ice cover melted almost everywhere in Greenland at the same time, which is extremely unusual.

So it's still got almost all of its ice, but there's a thin sheet of water on top. It's weird and strange, but it's not an actual loss of ice cover, which would be catastrophic.
posted by Malor at 9:54 AM on July 25, 2012 [1 favorite]


That's cool. It's still a pretty amazing event, and we'd best hope against hope that it is a 1 in 150 years things and not...you know what.
posted by Jehan at 9:54 AM on July 25, 2012 [2 favorites]


This scares me so much I'm about ready to turn into a climate change denier just so I can sleep at night. I have to say I'm seriously looking forward to somebody showing up and explaining why this isn't a big deal.

(I do understand that it's not as serious as you can read it, but it still seems awfully 'you know what', to use Jehan's phrase)
posted by MCMikeNamara at 9:55 AM on July 25, 2012 [2 favorites]


Remember when you were 8 and you realized Greenland was icy and Iceland was green. Yeah.
posted by Fizz at 9:56 AM on July 25, 2012 [17 favorites]


Maybe a mod could help me out and finesse the wording: "...rapid loss of 97% of its surface ice cover" to read: "...rapid loss across 97% of its surface ice cover," or something similarly more precise.
posted by saulgoodman at 9:57 AM on July 25, 2012 [2 favorites]


"rapid melting across 97% of its surface ice cover"
posted by Picklegnome at 9:59 AM on July 25, 2012


So it's not that Greenland's ice is 97% melted, it's that some melt has occurred over 97% of Greenland's ice. Which is not entirely "unprecendented" in that, as the article says:
The last such melt event occurred in 1889, according to data from ice cores, and scientists say they would expect such an event about every 150 years
i.e., we were about due for it to happen.

I'm not trying to minimize the seriousness of it, just that it's unclear from the information from the article whether or not it is an alarming development, or just a rare one.
posted by xigxag at 10:00 AM on July 25, 2012


What's unprecedented, as I tried to emphasize with the word "Rapid" is the pace of melting. There's no indication this much melting has ever occurred this quickly, even though there's been melting on this scale before, this is faster than anyone thought possible, is the point.
posted by saulgoodman at 10:02 AM on July 25, 2012 [1 favorite]


"...rapid loss of 97% of its surface ice cover" to read: "...rapid loss across 97% of its surface ice cover,"

That would have kept the coffee off my computer monitor.
posted by BeeDo at 10:03 AM on July 25, 2012 [1 favorite]


What's unprecedented, as I tried to emphasize with the word "Rapid" is the pace of melting

That's the important part. Yes, large surface cover loss does happen in Greenland, but the previous evidence is that this was a year-to-multiyear process. Not five days.
posted by eriko at 10:04 AM on July 25, 2012 [6 favorites]


This scares me so much I'm about ready to turn into a climate change denier just so I can sleep at night.

I think this drives a lot of denial-ism cause having to deal with OH GOD WE BROKE THE PLANET is overwhelming.
posted by The Whelk at 10:04 AM on July 25, 2012 [28 favorites]


It's the speed that should leave you doing a spit take; change on this scale has always happened much more slowly.
posted by saulgoodman at 10:04 AM on July 25, 2012


We can just legislate and make it illegal to measure this, that way it won't happen.
posted by Ghostride The Whip at 10:07 AM on July 25, 2012 [18 favorites]


So, what's the forecast there for the remainder of the summer?
posted by jbickers at 10:08 AM on July 25, 2012


[Tweaked the post phrasing per request, carry on.]
posted by cortex at 10:10 AM on July 25, 2012 [2 favorites]


It's a balmy 61 °F in Nuuk right now.
posted by theodolite at 10:11 AM on July 25, 2012


One important implication of this is that current climate models of sea-level rise don't account for the possibility of ice loss at the rates currently being seen in Greenland and Antarctica. So all those international climate reports and such on the projected (already ugly) rate of sea-level rise due to climate change are out the window. Sea levels are likely going to rise much faster than anyone expected.
posted by saulgoodman at 10:12 AM on July 25, 2012 [2 favorites]


If it's warm enough to melt surface ice at the highest glacier elevations, wouldn't it follow that all of the lower elevations are also warm enough for melting, all the way down to the coast? It's not like icewater from the highest peak forms a stream that freezes half way down the slope, like an icicle, does it?

What's the part that I'm (obviously) missing: that it's rare for the highest elevations to reach this temperature, or maybe that it's rare for a warm mass to be big enough to cover the entire land area of Greenland?
posted by ceribus peribus at 10:14 AM on July 25, 2012


Anyone pointing to the Greenland melt as a definite Global Warming Event is as guilty of scientific fallacy as the loonies denying that humans are causing global climate change.
posted by Nelson at 10:16 AM on July 25, 2012 [2 favorites]


So, what's the forecast there for the remainder of the summer?

DOOM!

Seriously, though, this is not good.
posted by entropicamericana at 10:17 AM on July 25, 2012


Gather thee rosebuds while ye may.
posted by "But who are the Chefs?" at 10:23 AM on July 25, 2012


is as guilty of scientific fallacy as the loonies denying that humans are causing global climate change.

Note: Seems like false equivalence to me, since there's actually some hard physical evidence, even if it's not definitive, for the former view, while the latter view remains exclusively a waking wish-fulfillment dream. It definitely relates to global warming at least in the sense that it's an obvious and good candidate for a possible consequence of AGW.

To suggest the possibility of a link, while such a link may not yet be a definitive, causal one, is obvious and couldn't be more reasonable: One way or another, this is another result that evokes the issue of Global Warming because it's quite reasonable to consider the possibility this is AGW related (as real climate scientists are and should rightly be investigating).
posted by saulgoodman at 10:26 AM on July 25, 2012 [6 favorites]


I wanna stop the world so I don't melt with Nuuk.
posted by argonauta at 10:28 AM on July 25, 2012 [4 favorites]


I believe this last happened 150 years ago, and I guess this time around it's related to the Jet Stream trapping warm air over Greenland while pushing cool air towards the European Atlantic Seaboard.
posted by KokuRyu at 10:32 AM on July 25, 2012


Yes, large surface cover loss does happen in Greenland, but the previous evidence is that this was a year-to-multiyear process. Not five days.

Five days sounds reasonable to me. I assume "melted" means a very thin layer of water covering the ice, which could happen on any sufficiently warm day. So the surprising bit was just that enough warm air got trapped over Greenland for that period of time. I don't see mention of any specific process at work other than the "heat domes" but these sound like local weather phenomena.
posted by RobotVoodooPower at 10:42 AM on July 25, 2012


Anyone pointing to the Greenland melt as a definite Global Warming Event is as guilty of scientific fallacy as the loonies denying that humans are causing global climate change.

Global warming is real, it's just that nothing is caused by it.
posted by IvoShandor at 10:42 AM on July 25, 2012 [7 favorites]


Paging Denis Quaid
posted by Damienmce at 10:44 AM on July 25, 2012 [1 favorite]


As theodolite and others above have pointed out, the coverage of these data is overstated and overadjectived. Climate change is real but reporting like this is infuriating and damaging. The use of "unprecedented" is indefensible, as we know this degree of melting happens every 150 years and we don't know the speed of melting in those earlier incidents.

Every time someone argues that the reality of climate change is demonstrated by "we haven't had [temperatures/drought/weather extreme] like this since [insert year]" they are undermining their own point. Trends are real and frightening and important. Breathlessly reporting incidents like this just undermines efforts to get people to understand and pay attention and support efforts to do something.
posted by twsf at 10:45 AM on July 25, 2012 [1 favorite]


Anyone pointing to the Greenland melt as a definite Global Warming Event is as guilty of scientific fallacy as the loonies denying that humans are causing global climate change

Nonsense. If you are weighting the dice, then it is rational to point to the dice as the cause of a specific result. Sure with normal dice you might also roll snake eyes, but we pick an individual roll of the loaded dice and say it wasn't because of the dice. AGW now plays a significant Rome in every major weather event.
posted by humanfont at 10:46 AM on July 25, 2012


So when this happens again next year, or next week, or in 2016, will that be enough to move us to act? Doubt it. I'm sure we'll be "right on time" for that one too.
posted by twjordan at 10:48 AM on July 25, 2012 [1 favorite]


Well of course there's the possibility of a link between Global Warming and the Greenland melt. And that's a legitimate and interesting scientific question. I'm just reacting to the commentary I've already seen about this online, including here on Metafilter, that "omg teh ice melted it's global warming!". All wrong thinking impedes science, whether it's on the side of the probable truth or on the side of the crazy.

Part of what makes human caused climate change so complicated and dangerous is that it's such a subtle, slow, enormous phenomenon. Pointing at freak snowstorms or hot summers or a year's drought as definitive evidence of global warming is a fallacy. The notion of "cause" when it comes to the relationship of climate and daily weather is complicated; that complication is part of why it's such a difficult scientific and public policy question. Thinking clearly is our only hope for understanding the science and using that to drive the politics.

As the article notes, apparently this kind of melt happens roughly every 150 years (sadly, no standard deviation is offered in the article). The last one was roughly 120 years ago. It's not clear the melt event is even that unusual. It's also unclear if a general rise in global temperatures would make a Greenland melt more or less likely. If the immediate cause of the melt is a rare periodic phenomenon where warm air shifts north and is trapped over Greenland, that could be more likely if the earth is warming, or cooling, or neither. It's some complicated effect of global wind patterns, something not well understand. I don't really know and unless we have any experts here, no one else on MeFi does either.

I don't want to sound like some crazy denying Global Warming. I'm absolutely convinced our industrialization is destroying the planet and if we don't do something about it, we will wreck the world. And I fear it may be far too late to even begin, but we have to try. I just want to talk about it in a rational way so the scientists have space to do the science and so the politicians make decisions based on science and reality, not today's breathless news.
posted by Nelson at 10:53 AM on July 25, 2012 [3 favorites]


Five days sounds reasonable to me.

I guess this is just one of those cases where it makes sense to me to defer to the judgment of the folks who study this particular area of climate science, and they generally seem to agree this is a potentially big deal, particularly, if we see similar scale melts again in the near term.

More about the forecasts for the region here on the Wunderground site:
While Greenland's ice isn't going to be melting completely and catastrophically flooding low-lying areas of the earth in the next few decades (sea level is only rising about 3 mm per year or 1.2 inches per decade at present), the risk later this century needs to be taken seriously.
posted by saulgoodman at 10:57 AM on July 25, 2012


The use of "unprecedented" is indefensible

But it is unprecedented, in terms of what we've seen in the years since we've been tracking this data in real time. Ice core data is a less direct line of evidence than direct observation. This is still an unprecedented direct observation.
posted by saulgoodman at 10:59 AM on July 25, 2012


I believe this last happened 150 years ago,

...But not in four or five days.
posted by rtha at 11:04 AM on July 25, 2012


I'm absolutely convinced our industrialization is destroying the planet and if we don't do something about it, we will wreck the world.

Destroying the planet sounds extreme. I know very little about global warming, but the idea that "we" will do something enough to significantly curtail industrialization and carbon emissions anywhere in the near future (the next few centuries) seems like pie in the sky thinking. Has anyone actually modeled realistic global strategies to combat global warming to see how effective they would be? It doesn't seem to me there will be significant reduction in fossil fuel usage until all easily retrievable fossil fuel has been exhausted.
posted by Golden Eternity at 11:06 AM on July 25, 2012


Sounds like a great time to invest in Greenland Real Estate.
posted by Renoroc at 11:10 AM on July 25, 2012


I was thinking Thunder Bay, myself.
posted by seanmpuckett at 11:11 AM on July 25, 2012 [2 favorites]


...But not in four or five days.

Maybe.
posted by smackfu at 11:12 AM on July 25, 2012


Does some article talk about how fast the 1889 melt happened? I see nothing about it in the NASA or Wired article. I'm guessing given that it's ice core data, we don't really know. That's more of a yearly record, not a daily record, right?

I'd also like to understand more what exactly is being measured when NASA says "on July 8, about 40 percent of the ice sheet had undergone thawing at or near the surface. ... an estimated 97 percent of the ice sheet surface had thawed by July 12." What exactly does the satellite measure? How much ice melted? How close is the ice to melting every other summer?

Sorry to keep harping on scientific accuracy here, but this kind of phenomenon is really complex and I have just enough background to appreciate the complexity without understanding it. Part of why global warming politics are such a disaster in the US is our politics is inherently anti-scientific and our scientists don't always have much success communicating. I'm an optimistic, hoping that clear and accurate communcation will eventually move the political debate towards doing something about climate change before we're all doomed.
posted by Nelson at 11:14 AM on July 25, 2012 [1 favorite]


Melt water is very important factor in the dynamics of glacial flow. The rate at which glaciers flow to the ocean is controlled largely by friction on the surface of the rock under the glacier. When lots of melt water penetrates through crevasses to the base of the glacier, under high pressure it provides lubrication that dramatically increases the flow of the glacier. A rapid increase in melt water has a multiplying effect in loss of glacial ice.

A second controlling factor for glaciers that end in the ocean are the floating ice shelves at their ends. These shelves form a kind of dam that slows the flow of the glacier behind them. When the shelves break off, as in the example from last week, the glacial flow rapidly speeds up.

These are just two examples of positive feedback multipliers that make these incidents much more significant.
posted by JackFlash at 11:19 AM on July 25, 2012 [4 favorites]


The Story Behind Record Ice Loss in Greenland. As usual ClimateCentral has an excellent take on things. I was taken by the video at the end, showing the melt river wiping out a 60-year old bridge. Looking at all that water flowing into the ocean, very violent and sudden. There are more Greenland-raging-melting-water videos in the related videos on YouTube.
posted by stbalbach at 11:25 AM on July 25, 2012 [6 favorites]


Also, the rapidity of increasing melt water is important. A sudden burst in the flow of water creates high pressure under the glacier, lifting and lubricating, because there is nowhere for the water to go. Eventually, the water will carve out under-ice channels that relieve the water pressure. So rapid surface melting over a few days is very significant.
posted by JackFlash at 11:28 AM on July 25, 2012


KokuRyu: "I believe this last happened 150 years ago, and I guess this time around it's related to the Jet Stream trapping warm air over Greenland while pushing cool air towards the European Atlantic Seaboard."

related previous
posted by stbalbach at 11:29 AM on July 25, 2012 [2 favorites]


yeah, what jackflash said...that surface water is bad...it's heavier than ice and a liquid, so it tends to pool in cracks and then sink through the ice, cutting it into smaller, easily melted chunks and etc...
ghastly...
posted by sexyrobot at 11:40 AM on July 25, 2012


They have tried to fool us with this one before when they called it Greenland. Do not believe them!!
posted by srboisvert at 11:47 AM on July 25, 2012


lalalalalalalalalalalalalalalalalalalalalalalalalalalalala
posted by Karmadillo at 12:05 PM on July 25, 2012 [3 favorites]


I have to say I'm seriously looking forward to somebody showing up and explaining why this isn't a big deal.

Okay. I suppose it spells certain DOOM if your livelihood depends on figure skating in the middle of Greenland.

Seriously, sea-level rise is the most over-hyped problem of global warming. Sure it'll be disruptive, but if the worst that happened was that some fraction of everyone had to move to higher ground, it's not like that would be the end of the world. Inconvenient for a bunch of small island nations such as Tuvalu and Manhattan, but the world would go on nonetheless. And if Greenland melts faster than expected, that just means whatever sea level you'd previously expected to have 200 years from now will instead happen 100 years from now. Or something like that. It's not even the most alarming news about the weather I've seen this week.
posted by sfenders at 12:11 PM on July 25, 2012


What exactly does the satellite measure?

Have you ever heard a TV meteorologist mention that radar doesn't reflect off snow as well as it does off rain? That same physics is how the melt signature was measured.

Two of the satellite instruments mentioned are measuring microwave radiation, one passive, (where it is just measuring the natural microwaves either bouncing off of, or emitted by, the surface), the other active (where the instrument measures returns from a microwave radar signal sent down to the earth). The microwave signal for melt water is much stronger than it is for ice or snow cover, so melting is pretty obvious in the satellite data.
posted by plastic_animals at 12:16 PM on July 25, 2012 [1 favorite]


Greenland's average temperature has already risen 1.5° since 1951. Basically, nothing else matters. No political programme, no plans to raise kids, nothing: we fix this very quickly or the planet becomes massively uninhabitable.
posted by imperium at 12:21 PM on July 25, 2012


the planet becomes massively uninhabitable

citation needed
posted by Golden Eternity at 12:26 PM on July 25, 2012 [1 favorite]


...but if the worst that happened was that some fraction of everyone had to move to higher ground, it's not like that would be the end of the world.

There's also the part where ice is very shiny and reflects 90% of incident sunlight back into space (according to what we all saw in Inconvenient Truth), thereby preventing (radiating) a lot of heat that would otherwise be part of our global climate. The act of melting glacier ice into water also consumes large amounts of heat. It's a positive feedback cycle. Merely losing the heat sink of Greenland's glaciers will itself raise global temperature.
posted by ceribus peribus at 12:36 PM on July 25, 2012


yeek
posted by LobsterMitten at 12:46 PM on July 25, 2012


citation needed

Yeah the results of climate change may be quite bad but "massively uninhabitable" isn't really on the table.
posted by Justinian at 12:50 PM on July 25, 2012 [1 favorite]


The Whelk: "This scares me so much I'm about ready to turn into a climate change denier just so I can sleep at night.

I think this drives a lot of denial-ism cause having to deal with OH GOD WE BROKE THE PLANET is overwhelming.
"

Yeah, but Jesus is coming back to fix it all up nice and pretty after the rest of you heathens get to suffer through the TRIBULATION!
posted by symbioid at 12:57 PM on July 25, 2012






Yeah the results of climate change may be quite bad but "massively uninhabitable" isn't really on the table.

Depends on your time scale. The best science available currently says that half the world will be "massively uninhabitable" (due to limits to human heat tolerance) by 2300. That's a problem not on the scale of epochs, but human generations. If the current models are wildly underestimating the pace of warming due to underestimating feedback effects, then it might be even sooner. To be clear, no climate scientists are seriously predicting that happening in our life times now, but they all seem to be scratching their heads saying "Well, this is all consistent with previous projections--only it's all happening a lot faster than expected."

Being too alarmed by the latest evidence may be a bad idea, but not being alarmed enough seems like an even worse one.
posted by saulgoodman at 1:10 PM on July 25, 2012 [5 favorites]


Sub "may be" for "will be" above. Don't mean to oversell it.
posted by saulgoodman at 1:12 PM on July 25, 2012


What Will Be the Biggest Political Story of 2032?

Pictorial representations of a politician's genitals that he or she transmitted to an intended sexual partner using a common telecommunications method.
posted by ROU_Xenophobe at 1:16 PM on July 25, 2012 [2 favorites]


"Happening a lot faster than expected" has been the refrain for at least a decade. I take all predictions with a pinch of salt: chances are, they aren't nearly pessimistic enough.
posted by five fresh fish at 1:50 PM on July 25, 2012 [2 favorites]


saulgoodman: That's not really what the reports say. They say that there could be a lot of areas that sometimes reach above 95F wet bulb temperatures if the average temp rises more than 21F. But that's a really bug "IF". I don't believe current consensus thinking is that temperatures will rise that much.
posted by Justinian at 1:57 PM on July 25, 2012


Seriously, sea-level rise is the most over-hyped problem of global warming. Sure it'll be disruptive, but if the worst that happened was that some fraction of everyone had to move to higher ground, it's not like that would be the end of the world. Inconvenient for a bunch of small island nations such as Tuvalu and Manhattan, but the world would go on nonetheless. And if Greenland melts faster than expected, that just means whatever sea level you'd previously expected to have 200 years from now will instead happen 100 years from now. Or something like that. It's not even the most alarming news about the weather I've seen this week.

Sea level rises mean loss of land use not just through inundation, but also through increased salinity of coastal groundwaters and surface water. Coupled with the fact that the most productive agricultural lands are typically low-lying areas along the coast and river valleys, there's potentially a significant loss of agricultural land from sea level rises, not just for island nations but also for anyone with significant deltas or coastal floodplains. It's a lot harder to relocate farms onto less-fertile upland geology than it is to relocate people and towns.

It's true that the popular imaginings of the entire world becoming flooded are unlikely, and the results are going to be complex and contingent upon local conditions. But neither are the consequences easily dismissible.
posted by talitha_kumi at 2:02 PM on July 25, 2012


Interesting we just had a leap second.

Melting of ice packs on land at high latitudes would tend to lengthen the day.
posted by jamjam at 2:45 PM on July 25, 2012


Well of course there's the possibility of a link between Global Warming and the Greenland melt

It is a near certainty that the events are linked. You seem to like to teach the controversy.
posted by humanfont at 2:58 PM on July 25, 2012


sfenders: "Seriously, sea-level rise is the most over-hyped problem of global warming. Sure it'll be disruptive, but if the worst that happened was that some fraction of everyone had to move to higher ground, it's not like that would be the end of the world. Inconvenient for a bunch of small island nations such as Tuvalu and Manhattan, but the world would go on nonetheless."

Well, you know, other than the literally billions of people having to relocate and billions of acres of land (and importantly for us humans, infrastructure) flooded with salt water it won't be a big deal at all.

Justinian: "Yeah the results of climate change may be quite bad but "massively uninhabitable" isn't really on the table."

Haven't paid much attention to the US corn crop this year, I take it? Those of us in the middle of the country are having the worst drought since the 30s. Models are fairly consistent in showing that in a warmed environment, this will be the new normal. I would say that not being able to grow food (corn, cattle, everything is dying out here) across much of the US that presently does grow food will indeed make the planet largely uninhabitable for most of us.

The worst part is that most of Europe, Africa, South America, and Asia will find themselves in the driest part of the subtropics thanks to the weather patterns shifting. Russia will be in great shape, though, so long as they all move out to Siberia, where it will no longer be so cold and dry. Should be quite pleasant. Unfortunately, very little of Earth's land area will be so situated.

Obviously, none of this is going to come to a head next week, but this is what the next century looks like if we don't immediately reduce global emissions (great that we've accidentally reduced some of ours thanks to cheap natural gas) and embark on vast atmospheric modification projects. I prefer just removing much of the carbon from the atmosphere, but there are proposals to offset the warming by emulating the effects of volcanoes.

Unfortunately, all solutions that don't involve just stopping the emissions and waiting it out also require vast amounts of energy. Energy that will make the problem worse if we don't build some carbon-neutral(ish) energy sources. Even after Fukushima I am so beyond worrying about nuclear contamination. The radiation released in that disaster will kill a few people slowly and eventually dissipate. The climate change is going to cause our species to dwindle to near nothing over the next few centuries, assuming we don't get some reprieve from something like the Yellowstone supervolcano lighting off. That would be pretty crappy for us North Americans, but the parts of the world that were undevastated enough to care would see temporary cooling that might give them time to get their house in order.
posted by wierdo at 4:07 PM on July 25, 2012


> (great that we've accidentally reduced some of ours thanks to cheap natural gas)

And a honking big recession. Pray it continues.
posted by jfuller at 4:25 PM on July 25, 2012


Damnit, I just sacrificed the last of my virgins during Venus' transit. What do I have to work with now?

Also:

Inconvenient for a bunch of small island nations such as Tuvalu and Manhattan

Um.
posted by Halloween Jack at 4:56 PM on July 25, 2012


If it helps any, Greenland is pretty much a basin so much of its ice will have to melt - and not just slide sideways - before it joins the seas.

If you calculate the phase-change energy alone needed to convert Greenland's 2,930,000 km3 of ice into water, you'll see that it's going to take a while. The ice-to-water PCE is 79.7 cal/gm or 316 BTU/kg. (Roughly all the energy in a gallon of gasoline for 100kg.)

One km3 of ice weighs 1 Trillion (10^12) kg. Do the math. Answers up on the board in the hallway when I get back from Tahiti.
posted by Twang at 5:32 PM on July 25, 2012


Unfortunately, the sun provides a lot of energy that is reflected into space when the surface of the ice sheet is frozen and that is absorbed rather efficiently when it is not.
posted by wierdo at 5:53 PM on July 25, 2012


Twang, it's a basin because of the weight of the ice pushing down on the land, it will rise as the ice melts. Notice how the land is lowest at the point where the most ice is sitting overhead. The other thing is, scientists still don't understand fully how ice sheets melt. It could reach a tipping point with new phenomenon that speeds it up. Lots of ongoing research in this area.
posted by stbalbach at 8:09 PM on July 25, 2012


Wait a minute. This is a trick question. Ice floats, and Greenland is mostly made of ice, so the mean sea level won't change at all if it melts. It's like Aristotle in the bath - he jumped out because it was too hot but the water level didn't change so he said "Eureka!" and ran off to tell the king, but a soldier killed him on the way.
posted by Joe in Australia at 9:49 PM on July 25, 2012


I'm pretty sure Greenland is going to be surprised to discover they're an iceberg and not a landmass covered in ice, Joe.
posted by five fresh fish at 10:59 PM on July 25, 2012


OTOH, you could be joking. Hard to tell through the accent.
posted by five fresh fish at 11:00 PM on July 25, 2012


And consider that a moving glacier is just like a conveyor belt and what that means.
posted by JackFlash at 11:51 PM on July 25, 2012


It's like Aristotle in the bath - he jumped out because it was too hot but the water level didn't change so he said "Eureka!" and ran off to tell the king, but a soldier killed him on the way.

It was Archimedes, actually. He was kill later by a Roman soldier during the Siege of Syracuse.
posted by homunculus at 11:58 PM on July 25, 2012


Surely this can be fixed by lowering taxes on the leading ice-making industrialists.
posted by snuffleupagus at 7:29 AM on July 26, 2012 [3 favorites]


Sell the glaciers and let the owners sue the people responsible for global warming! At one stroke we would have created a new financial resource, given employment to millions of lawyers, and averted environmental capacity! What could go wrong?
posted by Joe in Australia at 8:04 PM on July 26, 2012


and averted environmental capacity!

Yep!
posted by rtha at 8:41 PM on July 26, 2012


Gotta avert environmental capacity at all costs!
posted by saulgoodman at 6:24 AM on July 27, 2012








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