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Grim Picture of Polar Ice-Sheet Loss
ananyo writes "A global team of researchers has come up with the most accurate estimate yet for melting of the polar ice sheets, ending decades of uncertainty about whether the sheets will melt further or actually gain mass in the face of climate change. The ice sheets in Greenland and Antarctica are melting at an ever-quickening pace. Since 1992, they have contributed 11 millimeters — or one-fifth — of the total global sea-level rise, say the researchers. The two polar regions are now losing mass three times faster than they were 20 years ago, with Greenland alone now shedding ice at about five times the rate observed in the early 1990s. This latest estimate, published this week in Science, draws on up to 32 years of ice-sheet simulations and 20 years of satellite data to give an estimate two to three times more accurate than that in the last IPCC report."
LALALAALAAA we can't hear you.
I for one look forward to being an island-dwelling overlord...
We have a spare on Mercury.
Strange things are afoot at the Circle-K.
Everybody raise their houses by 2cm, quick!
Given that the article is pay-walled, is there any prediction about ice loss? What are the most recent predictions that have given accurate result in the past?
Video of some good progressive thrash music
I predict:
People who don't believe in AGW/man made climate change will think that this study is just part of the conspiracy
Most people who do believe in AGW/man made climate change will continue to suggest remedies that just will not happen due to economics/human nature
The small amount of actually useful discussion of how we can adapt to a changing climate (no matter what it's cause) will be drowned out in the accusations and counter accusations
55mm in 20 years, 11mm due to ice loss, a bunch more due to thermal expansion of the oceans which is also AGW-related.
5cm may not sound like much to you, but to someone looking for a 30+ year real estate investment, and observing this trend of accelerating ocean rise, it will effect property valuations for some coastal property. Especially since the expectation is that, unchecked, this measurement will eventually be in meters.
Someone had to do it.
So, you came up with a model that accurately predicts the past?
What nonesense is that? The accuracy of a model can only be determined by testing it against reality, and not against the data it has been fitted to. You need new data to do that and I'm sorry to tell you that new annual data sets will arrive only at a pace of one per year.
Meanwhile, shut up and look at the models you've made so far and be ashamed of the constant revisions in both directions.
In any other branch of science coming up with the kind of models and inaccuracies that climate science comes up with, scientists would simply say .. well, sorry, we cannot model these processes with any degree of accuracy and be done with it. If you came up with a better model, well, good for you, but now you have to *prove* it is actually better than all the rest so far.
Problem is that for most people it doesn't gel with their personal experience.
If The Scotsman newspaper runs this news then it's a guarantee that for a couple of days following the article the letters page would be full of "It was snowing here; so much for global warming" and "But I saw ice on the ground this morning" and similar variants.
And yes, I know it's my own fault for reading the letters page in The Scotsman.
Got into a discussion about this recently over the recent (and on-going) flooding in the UK. If the sea level and temperatures both rise, then a logical expectation of that would be that more water would evaporate off the oceans into the atmosphere, subsequently returning as rain and snow. That would entail more runoff and a corresponding rise in river levels and increased risk of flooding, particularly given the growing pressure on housing in some areas resulting in flood plains being used for development.
It's not just the people with beachfront properties that need to be worried...
UNIX? They're not even circumcised! Savages!
It's been happening for the the last 12K Years, I think it is about time someone took notice.
Only in a small zone near the freezing point.
Someone had to do it.
For 0 to 4 degrees C it contracts but warmer than that it expands. Water Physics_and_chemistry
There's a difference between coming out of an ice-age (a natural process over tens of thousands of years) and global warming, where there is a noticeable change in temperature/ice-caps over a period of years/decades.
And it's trolls like you spreading FUD that don't help matters.
but to someone looking for a 30+ year real estate investment, and observing this trend of accelerating ocean rise, it will effect property valuations for some coastal property.
I live about 15 miles inland, so raising seas will actually increase my house value because I'll then be able to sell it as having a sea-view! /sarcasm
Genius. I'll break out the 1000-mile wide scale, you lift greenland onto it.
Someone had to do it.
Polar ice is Cartesian ice after a coordinate trasformation.
Mastering the English language is fucking easy: all you have to do is to put an f* word in every fucking sentence.
Easiest way to fix sea level rises is to dig two channels.
Connect the Caspian Sea and the Dead Sea (and the rest of the Great Rift Valley) to the open ocean and watch the water level drop.
I'm guessing that wasn't on their radar screen...
http://www.skepticalscience.com/greenland-used-to-be-green.htm
Lots of things cause climate change.
Work Safe Porn
Everything is AGW related - hot spells, cold spells, droughts, floods, riots, earthquakes, locusts, hurricanes, doldrums - that's a cop out.
The fact of the matter here is that 11mm in 20 years, or 55mm in 20 years, is ridiculously small. Seriously, 6 *centimeters* in 20 years. Even with a thirty year horizon, that's not more than 10 *centimeters*.
Quick quiz: how much did ocean levels rise from 1900-2000, and how many acres of real estate were devalued because of it?
As for acceleration, sea level rise is actually *slowing* - there's simply no possible plausible scenario that is going to turn *millimeters* of change into *meters* of change in in 20 years, or even 100 for that matter.
If the sea level would just rise about 30 more meters or so my house would be on the beach, plus -- and this is a big plus -- no one would ever have to smell New Jersey again.
55mm in 20 years, 11mm due to ice loss, a bunch more due to thermal expansion of the oceans which is also AGW-related.
BS. If you look at the actual data you'll note that the rate of sea level rise has decreased since 2002. This is entirely inconsistent with a) the claim being made by these researchers and b) the idea that the current high levels of atmospheric CO2 are causing unusual warming, swamping natural variability.
The ocean heat sink is supposed to receive something like 80% of the AGW related heat increase, causing thermal expansion as you state.
"Forget the experimental evidence - it's ruining our beautiful theory!"
Galileo: "The Earth revolves around the Sun!"
Score: -1 100% Flamebait
The refugees squatting on your front lawn might drastically lower the value, though.
Ubi solitudinem faciunt, pacem appellant.
it is incredibly foolish to believe that humans are responsible for the melting of the polar icecaps. one volcano eruption puts off more CO2 than all of the emmissions that humans have put out since there were humans.
That statement is factually incorrect. Volcanos do not emit more CO2 than humans-- they emit less, by orders of magnitude.
http://www.agu.org/news/press/pr_archives/2011/2011-22.shtml
http://hvo.wr.usgs.gov/volcanowatch/archive/2007/07_02_15.html
http://www.agu.org/pubs/pdf/2011EO240001.pdf
http://www.skepticalscience.com/volcanoes-and-global-warming.htm
http://www.newscientist.com/article/dn11638-climate-myths-human-co2-emissions-are-too-tiny-to-matter.html
From http://news.sciencemag.org/sciencenow/2011/06/scienceshot-volcano-co2-emission.html :
"A popular myth among climate change skeptics is that volcanic emissions of carbon dioxide dwarf those generated by humans. But a new report in today's issue of Eos reveals precisely the opposite: In a mere 2 to 5 days, smokestacks, tailpipes, and other human sources of CO2 spew a year's worth of volcanic emissions of that greenhouse gas. According to the paper, five recent studies suggest that volcanoes worldwide (such as Alaska's Shishaldin, shown) emit, on average, between 130 million and 440 million metric tons of CO2 each year. But in 2010, anthropogenic emissions of the planet-warming gas were estimated to be a whopping 35 billion metric tons. Individual events—such as Mount Pinatubo, whose major eruption in 1991 lasted about 9 hours—can produce CO 2 at the same rate that humans do, but they do so only for short periods of time. It would take more than 700 Mount Pinatubo-sized eruptions over the course of a year to emit as much carbon dioxide as people do, the study notes."
Let me note that it is misinformed statements like this that tend to make real scientists dismiss global-warming deniers as crackpots. If you really want skepticism of anthropogenic global warming to be taken seriously, you need to have a basic understanding of the real world.
http://www.geoffreylandis.com
Amazing how denialists don't trust any data that doesn't match their preconceptions but are only too willing to make pretty wild assumptions when they find some vague hint of something that might help confuse the issue.
If you think someone isn't free to have a different definition of "freedom" you may be a tyrant.
If your prediction is correct, then global warming will be a good thing for places like California, which can definitely use more water (and have the means for storing it if it comes all at once). Most of the Western US has water shortages and would not be upset at all if there were more rain.
"First they came for the slanderers and i said nothing."
So where the ice was 100 years ago before global warming started is exactly where "normal" is and where the ice should always have and forever have stayed?
Depends what you mean by the word "normal." The dinosaurs lived perfectly well in a world that had no ice caps at all, and in which the entire center of the United States was a shallow ocean that stretched from Colorado to Pennsylvania. You could call that "normal" if you like.
However, there would be a great deal of disruption to human civilization to change to that state. We have an ecosystem (and an economic system) that is well adapted for the climate we have now, not one that is significantly warmer and with significantly higher sea levels. It would cause trillions of dollars of costs just to relocate the part of the population that lives in places that will be underwater, not even to mention changing the agricultural infrastructure. Doing this slowly is one thing. Doing ten thousand years worth of climate change in fifty years is another.
It would be nice for Canada, Norway, and Siberia, though. Not so nice for the United States (except for Alaska); we have a very good climate for agriculture right now, and don't really want to have the climate of Mexico move up to Kansas. Oddly, Canada, Norway and Russia are the most adamant of the countries that are trying to block restrictions on greenhouse effect gas emissions. That's probably just a coincidence, though, since those countries are also major fossil-fuel exporters.
http://www.geoffreylandis.com
there's simply no possible plausible scenario that is going to turn *millimeters* of change into *meters* of change in in 20 years
Never said that. When buying a house, many purchasers want their kids and grandkids to be able to enjoy it as an inheritance. Coastal erosion is a well know source of devaluation. 5cm of average sea level rise translates to several meters on a flat beach.
Someone had to do it.
If you look at the actual data you'll note that the rate of sea level rise has decreased since 2002.
No, he'll see a denialist bufoon trying to split a 20 year graph of noisy data into two distinct sections. He won't see the scientist that actually created that data doing something so dumb.
You tried exactly the same back in 2009, to claim that global warming had stopped in 1998. However, 3 years more data of climing temperatures showed that you were exactly the idiot people said you were. Trying to make patterns out of short term noise.
Sahara desert = not much food.
Seems the world is more complicated than you imagine.
And you know what? eruptions/emission from volcanoes are relatively constant. They haven't changed significantly in the last 200 years. So what has changed in that time frame?
People in cars cause accidents....accidents in cars cause people
What the models point to is more extremes – some areas with severe flooding and storms, and other areas more like deserts.
Models are unable to predict at smaller then the continental scale (read the IPCC report). As an example,
California is not slated to get a wetter climate out of climate change.
This depends a LOT on whether El Niño becomes more common or less common, and models are also unable to predict that.
"First they came for the slanderers and i said nothing."
Unfortunately, California and the Western U.S. will likely be on the on the end where more water evaporates and other areas, like Seattle maybe, will be on the end where "more water precipiates". So California and the Western U.S. are likely to become more desertified, and unfortunately when they do get rain, the risk of flash flooding will actually be worse because more rain will fall and the land will be less able to absorb it.
Isn't climate change wonderful? The people who already "get too much rain" will get more and the people who already "don't get enough rain" will get less and have more of their aquifers evaporate.
Fanatically anti-fanatical
Costal erosion is orders of magnitude more impactful than a 5cm average sea level rise. In fact, an average 5cm sea level rise tells you *nothing* about how local costal conditions are going to respond -> there are plenty of places where the high tide level *falls* even as "average sea level' is on the rise.
Not to mention, a 5cm average sea level rise, even if completely evenly applied to every coastal area, is dwarfed by natural variation in tidal range.
Oh, and nice trick turning centimeters of *height* into meters of *length* :) A cute sophistry, but not very effective.
Except that Russia is not good place to do business (at least for manufacturing):
Endemic levels of corruption (higher than even China), a for sale judiciary, a regime that is intent on scaring away foreign capital, workforce that unsuited for large scale Chinese style factory deployment, oligarchical control of existing infrastructure and government, nontransparent capital markets, the list goes on and on.
As mentioned elsewhere, climate models aren't accurate enough to predict climate changes for features smaller than the continental scale (read the IPCC report). So these predictions are mainly guesses. A lot of what happens to California rainfall will be determined by what happens with ENSO, which climate models are also unable to predict. So be doubtful any time someone gives such a specific prediction.
In the case of California, it's not a problem if the rain comes more intensely, as long as there is more of it. The state is already prepared for having too much of its water all at once. 150 years ago, before dams were built, the central valley would be covered with feet of water every spring, then would dry up for the rest of the summer. If you drive through the valley and look at the soil, you can still see evidence of annual flooding, and where the flooding became less and less as the dirt turns to sandy loam.
"First they came for the slanderers and i said nothing."
...Given the fact that 1 eruption can change global climate for several years...
An eruption can change climate for several years... but not due to the emission of greenhouse gasses, which are trivial.
The aerosols from an eruption, however-- the ash and sulfates-- can block sunlight and have a significant cooling effect. This is a very real effect, and making sure that climate models correctly model the effect of historic volcano eruptions is a useful way of verifying the fidelity of climate models.
CO2 emissions from volcanoes on the other hand, are just not significant. It's somewhat hard comprehend the scale of 30 trillion kilograms of carbon dioxide, which is the amount emitted by humans per year, but if you picture a cube of coal about 10km on a side, that will start to give you an idea. This is much larger than the total of what is out by volcanoes, including both eruption and non-eruption emissions.
http://www.geoffreylandis.com
Please toe the party line. Global warming is always and everywhere, per definition, bad. It cannot possibly have any positive effects anywhere. It does its deeds in such a way that evil is maximized. That's how nefarious it it.
If you still don't understand, an example: if you are cold and your friend next door is hot, global warming will freeze you as dry as a funeral pyre and boil your friend in his flooded home. At the same time.
Flourescent (adj): smelling like ground wheat.
I'm skeptical that there exists any necessary and sufficient falsifiable hypothesis statement of catastrophic anthropogenic global warming. I challenge you to cite the one you believe in.
Without specifying who "the scientists" are. I might know less than Richard Lindzen, for example, but I certainly know more than Michael Mann :)
The nice thing about science is that it can be played without credentials - we don't have to rely on appeals to authority. We start with our falsifiable hypothesis statement, try desperately to find falsifications, and fail - we get closer and closer to truth that way.
So want to play science, or do you want to argue authority? :)
Actually, no, we don't.
http://notrickszone.com/2012/11/29/stefan-rahmstorfs-sea-level-amnesia-using-his-own-numbers-sea-level-rise-actually-dropped-3/
Frankly, rates of change in this system will *always* be changing. As it stands, they're not following the steady uptick in atmospheric CO2, which tends to cast doubt on any causal relationship from CO2.
My point is that sea level rise does *not* necessarily amplify effects of costal erosion. You're making an unsupported assertion there.
If I point out a costal area where the coastal erosion has been steady for the past 100 years, even though sea level has increased, will you accept that as a refutation of your assertion?
And if you are going to make an amplification assertion, will you quantify it? If sea level rise amplifies coastal erosion by a factor of 1.000000000001, should we care?
You clearly didn't even read what he posted because it specifically mentions the eruption of Mt. Pinatubo. It was the largest eruption the world has seen since 1912, yet it would take 700 of those eruptions a year to even match human annual output of CO2, much less dwarf it.
this clearly shows that humans are in no way responsible for global warming.
Unfortunately, it shows nothing of the sort.
It says that water vapor is the most significant greenhouse effect gas. Water vapor indeed is a greenhouse gas, but water vapor cycles in and out of the atmosphere based primarily on temperature. The hotter is is, the more water evaporates into the atmosphere; the colder it is, the more water condenses out of the atmosphere. So, basically, water vapor is an amplifying agent-- if you increase the temperature, more water evaporates, and the greenhouse effect increases. This is well known.
I would like to really suggest you read the IPCC Working-Group 1 report, "The Physical Science Basis of Climate Change" http://www.ipcc.ch/publications_and_data/publications_and_data_reports.shtml
You would be able to argue more effectively if you started out by being aware of what is already known.
http://www.geoffreylandis.com
No, the question is even deeper than that - I dispute that a warmer world is a worse world. I can stipulate to warming, and even some measurable effect of humanity's CO2 emissions to that warming, but I will assert that this is *not* damage.
1850 was colder than 2012. 1900 was colder than 2012.
Do we really want to return to the population and technology of 1850 or 1900?
Apocalyptic nuts will always find *something* to worry about, I suppose...
If you look at the actual data you'll note that the rate of sea level rise has decreased since 2002.
No, he'll see a denialist bufoon trying to split a 20 year graph of noisy data into two distinct sections. He won't see the scientist that actually created that data doing something so dumb.
First of all, genius, the scientists collecting that data apply a linear regression right there on the chart, to the "noisy data". If you do the same thing to the most recent ten years worth (I have) you'll see that there's a significant decrease in the trend. That is all perfectly legitimate analysis.
I'm a realist, and believe in emperical verification of theory. So far the warmist alarmist predictions have been quite poor. They are adept at constant revisionism though.
You tried exactly the same back in 2009, to claim that global warming had stopped in 1998. However, 3 years more data of climing temperatures showed that you were exactly the idiot people said you were. Trying to make patterns out of short term noise.
I guess you're unaware that temperatures have in fact not climbed statistically significantly since 1998. You should know your subject matter better - that will prevent you from making a fool of yourself.
We'll see how the trends go as the Sun continues into the next solar Grand Minimum.
We're currently approaching the weak maximum of Cycle 24, so we're most likely looking at a minimum of twenty years of low solar activity - similar to that during the Little Ice Age. That will be a great empirical test of the dominance of CO2 concentration as a warming influence.
Galileo: "The Earth revolves around the Sun!"
Score: -1 100% Flamebait
I'm skeptical that there exists any necessary and sufficient falsifiable hypothesis statement of catastrophic anthropogenic global warming. I challenge you to cite the one you believe in.
I don't know what the word "catastrophic" means here. I assert that the global climate models, which suggest that human-induced greenhouse warming has raised global temperatures by approximately 0.5 C and will continue to raise global average temperatures by an amount that is calculatable to within (currently) an error band of about 50%, is supported by the best data we have. Is that what you call "catastrophic" anthropogenic global warming? I would call it "paying attention to the science." If this is what your talking about, the model is falsifiable, and has, so far, passed the tests given to it.
The first good numerical integration with definite, reliable results was done in 1967. That's 45 years ago, which is a long enough run for random variations to be averaged out. What's the slope of the linear least-squares surface temperature data from then to now? Is it upward, or downward? Well, yes, turns out it's upward, as predicted. And, to well within the error bands, the model is quite accurate about the slope.
I'd like to invite you to dig up the paper, do the calculation, and verify this yourself.
http://www.geoffreylandis.com
Is there?
Do we have data with the accuracy and precision to measure annual global temperature differences to a degree where we'd be able to notice a trend of 0.5 degrees over a 100 year span?
No, we don't. We have some data points and statistical smoothing that says over the course of this thousand year period, the average global temperature was X +/- a degree and over that thousand year period, the average global temperature was Y +/- a degree.
There seems to be this fiction that's developed among the "True Believers" that we can actually know whether a swing of 0.5 degrees over a 100 year span is unusual. The fact is, we don't even have accurate measurements of the average global temperature before the late 1970s when we got decent weather satellites into orbit. The data between the 1930s and then came from reasonably well defined standards of measurement, but wasn't wide-spread enough to give us a very clear picture of the average global temperature. So that data gets tinkered with by a rather complex and varied set of statistical models designed to fix the problems. Anything before the 1930s came primarily from people with no formal training in collecting the data. In most of the data points used from before the 1930s, you had individuals with a very limited education checking highly inaccurate instruments in non-standard (quite often completely incorrect) ways, unreliably recording the data that was poorly collected, and collecting it at odd times (whenever they had spare time most likely). The result is a mess of non-standard data that's almost as poor resolution as the proxies used before widespread temperature measurement was available.
This is all a matter of resolution, and quite frankly we don't have it. To this day, we can't even get all the proxies to agree with one another, nor with the observed values. The various proxies will show you very rough trends over time and they'll give you very rough estimates of the temperature at a very roughly estimated period of time, but they all share one thing in common: not a one of them will give you the kind of accuracy and precision necessary to correctly identify a 0.5 degree change in temperature over a 100 year period.
None of this is to say the global temperature is not, on average, rising over the past 100ish years. The overall trend has been upward and we can roughly estimate that change at .5 degrees during that period. The problem is that we have nothing to compare this data to. We didn't have weather satellites or even an army of untrained janitors collecting temperature data in non-standard ways from poorly calibrated devices back 5,000 years ago. We have absolutely no way to know what kinds of temperature swings have happened globally in the past because the ways we determine the global average temperature from that long ago inherently smoothe the data and destroy short-term fluctuations. I cringe whenever I hear/read someone claiming this is unprecedented climate change because that's almost certainly not true and nobody alive today has any way to show scientifically that it is true. It's possible this is unprecedented without a catastrophic global event, but there's absolutely no way available to us today to determine that either.
Before you write me off as another infidel climate denier, understand that I'm not denying anything; merely pointing out the limitations of the data, instruments, models, and techniques we have today. That doesn't mean I think the past 100 years of warming has to be perfectly normal; the truth is I don't know and I don't think anyone else does either. What I think has happened is that over the past 50 years or so, we've gotten our first look at a tiny snapshot of data for the Earth's average temperature and it's been under the microscope ever since. In much the same way you suddenly notice every single tiny noise, bump or vibration your vehicle's engine makes once the "check engine" light comes on, we've been pouring over this data without any real context and it's gotten
-- "Government is the great fiction through which everybody endeavors to live at the expense of everybody else."