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Scientists Cut Greenland Ice Loss Estimate By Half
bonch writes "A new study on Greenland's and West Antarctica's rate of ice loss halves the estimate of ice loss. Published in the journal Nature Geoscience, the study takes into account a rebounding of the Earth's crust called glacial isostatic adjustment, a continuing rise of the crust after being smashed under the weight of the Ice Age. 'We have concluded that the Greenland and West Antarctica ice caps are melting at approximately half the speed originally predicted,' said researcher Bert Vermeeersen."
This estimate change means climate change has once again been proven wrong! Right? Right?
(Hint: No.)
No, it's just a change in one of the thousands of indicators. However that's only for the people who actually care for the science of climate change.
For the rest, this estimate will prove just about anything between the third coming of the messiah and the imminent destruction of the Earth by magnetic core spin reversal.
Some bright researchers managed to refine a previous model and come up with better and more accurate predictions. You may want to note how, contrary to some "skeptics" beliefs this wasn't suppressed or refused publication or any other such shenanigans. In the word of a famous person "When I'm proven wrong I change my opinion, what do you do ?".
"We all know that the ice is still melting (but slower than we thought)."
Given we know the rate of ocean rise with a high level of certainty. The interesting thing about this estimate is that it has flow on effects to other estimates, such that the amount of ocean rise due to thermal expansion could be higher than previously thought which could mean that the oceans thermal inertia is not as slow as we thought.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
No one claims the planet is dying. It may become quite uncomfortable for humans, though.
The Tao of math: The numbers you can count are not the real numbers.
For the rest, this estimate will prove just about anything between the third coming of the messiah and the imminent destruction of the Earth by magnetic core spin reversal.
Hey now! Some of us just believe one or the other, that this is a sign of Jesus' return, or that the Earth's magnetic core is going to stop. It's only a lunatic fringe of our organizations that believe ice loss means Jesus is coming to stop the Earth's magnetic core!
"The ice caps are increasing."
That particular hypothisis has been falsified to death, it now requires a blind faith in the hypothisis afterlife to believe it.
What "republicans and oil executives" need to falsify is this - Snowfall above 3000 meters in greenland is increasing as predicted by climate models. This has nothing to do with the gulf stream (which is not significantly slowing down), it's due to increased water vapour which in turn is due to a positive feedback from global warming. Overall the extra snowfall at high altitudes does not make up for the extra loss at low altitudes, the extra snowfall may even speed up the loss of glaciers by making them top heavy.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
science should be treated, as it was always intended, with a grain of salt.
Are we talking "grain of salt" as in "not taking it so seriously" or "understanding that some changes to scientific theory and predictions are bound to occur."
Not taking science seriously, such as thinking maybe the law of gravity won't really apply this time so you can jump off that building, or not really caring whether or not global warming is occurring is dangerous and fairly illogical. Understanding that scientific theories often change with new facts, but that those changes don't mean the whole thing is bunk, that's good.
Actually it just means that once again the new prediction for sea level rise falls outside of the 95% confidence interval reported in the IPCC reports. Again. Imagine the chances. They've made 3 predictions, all with 95% confidence intervals, and the new prediction falls out of all 3 of them (just like their next prediction fell outside the 95% range for their previous prediction, both for sea level rise and temperature, so actually we should square the 5%). So if their chances are accurately calculated, that they're this wrong should happen once in 10y * 1 / ( 5% * 5% * 5% ) = 80 000 years.
I'm not a global warming denialist, mind you ... this obviously means that for the next 80 000 years the IPCC will not make a single wrong prediction !
Actually this is really smart of those scientists. You see, once every 80 000 years they will make 3 sequential predictions, each wrong. It's like, really smart of them to do it right away, then they can be right for the next few dozen millenia ! Brilliant !
No one claims the planet is dying. It may become quite uncomfortable for humans, though.
Actually, since the average temperature of the earth is 15 degrees celcius, and the optimum for humans (and animal life in general) is 21 degrees celcius, it will be more comfortable. Also, if history of civilization, specifically the period immediately preceding the little ice age, is considered, there will be a LOT more arable and livable land accessible to humans (Greenland, Siberia, Canada*, for one) with a 6 degree rise in temperature.
Even if, yes, a rise like this will mean moving a number of large cities. Also, the change will have winners and losers (generally the winners will be more northern or more southern, and the losers more situated around the equator, but that's at best a very inaccurate rule of thumb).
* yes, global warming will mean Canada will become a livable place, even when you're more than 10 km from the US border.
Also, we may not understand exactly what effect was responsible for creating the sahara, it appears to have been a global cooling. Perhaps (we don't know) global warming will reverse this.
Nothing would please me more than to find out that, in fact, we aren't screwing up the planet after all and that future generations will be able to enjoy a stable climate and SUVs. Really, I hope that everything turns out just great. However, it still doesn't look like it, I think we will face some very tough times. I don't know whether this new data is correct or not, just like I don't know whether the old data was correct or not. But 164 gigatonnes of glacial ice melt per year still sounds like a lot to me, even if it is less than 362 gigatonnes, so I'm not going to become complacent just because it isn't quite as bad as we thought - note that the word "bad" is still in the situation.
Also, all this means is that Greenland and West Antarctica are contributing less than 1/4 of the annual rise in sea levels rather than accounting for more than half. I guess we have to keep looking to find where the rest of the rise is coming from. None of this evidence contradicts the rise in sea levels, which is going to displace millions of people.
> We all know that the ice is still melting (but slower than we thought).
This year we are going to see a new record low for arctic sea ice --- surpassing even the dramatic 2007 decline.
http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/seaice.recent.arctic.png
What's really startling is that this year, both the NE and the NW passages are completely open. This animation tells the story
http://arctic.atmos.uiuc.edu/CT/animate.arctic.color.0.html
Typically, shipping through the NE passage relies on Russian icebreakers. Judging by the satellite photos, at this point the icebreakers aren't needed
Source: cryosphere today http://arctic.atmos.uiuc.edu/cryosphere/
Actually, since the average temperature of the earth is 15 degrees celcius, and the optimum for humans (and animal life in general) is 21 degrees celcius, it will be more comfortable. Also, if history of civilization, specifically the period immediately preceding the little ice age, is considered, there will be a LOT more arable and livable land accessible to humans (Greenland, Siberia, Canada*, for one) with a 6 degree rise in temperature.
You're forgetting that a lot of currently arable land becomes swamp in this context. Remember, if the ice melts the conveyor stops, then the jet stream stops (it's powered by the conveyor which is powered by the thermal differential of ice to ocean) and then we have localized weather. That means some areas get craploads of rain, and some areas get almost none. Areas that are desert become soupy. Areas that are farmland become swamp. Areas that are now scrub become eligible to become farmland once it's cleared. Areas that are now forest begin dying because the trees are no longer in the zone in which they thrive.
This is not going to be a party if it lasts long.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
>>They've made 3 predictions, all with 95% confidence intervals, and the new prediction falls out of all 3 of them
That's why I especially like one prediction they did (in AR4, I think) that included no change in the predicted models for 10 years out within the error bars (which was something like +0C to +4C).
So even if there's no climate change, it verifies climate change.
But if there's +5C change, then, by golly, global warming has been falsified! The results didn't match prediction.
In all seriousness, though, I think there's a real paradox in what we consider falsification and verification in science if the above two statements are both true.
I no longer believe you, when you say that you would be "pleased" to hear that global warming isn't that big of a deal. If that were true, why are such stories buried and alarmist stories repeated even if based on incorrect data?
About 10 years ago, I also believed in global warming, however I stopped doing so. How is such a thing possible?
1. Climate Change
I had my first doubts about global warming, when they introduced the term climate change“ which the added claim that climate change“ may not just cause warming in some regions, but may actually cause cooling in others. So all of the sudden climate change“ may cause everything: Hot, cold, stormy, dry, wet, etc.
2. The first decade of the 21st century
If the “hockeystick” were correct, we should have experienced a record-breaking hot climate in every year or at least most years between 2000 and 2010, but that just didn't happen. Some people say that 2009 was the hottest year on the record and hotter than 1998, but even if that's true it does not really support the supposed runaway warming-scenario - at all. Now when from the 10 years following 1998 9 have been cooler and one has been warmer, that may show that the climate may be a little warmer than usual (after all 1998 has been the warmest on the record and 2009 may have broken that record), but it points more to a relatively steady climate that may be little bit too hot, but not at all to some runaway climate shift.
3. Alarmism
What also disturbs me a lot is the alarmism. The warm periods, no matter when we talk about humans (medieval warm period, little ice age, etc.) or life in general were always the better periods (where “better” means of course that more life can be sustained by the earth)
So the horror-scenarios don't make that much sense and are blown way out of proportion.
4. The “experts” opinion
It is always said that the “scientific consensus” is clear about global warming. Well, science is not a popularity contest and is also not democratic. The “scientific consensus” also said that therapy and short prison sentences would reduce crime, but crime rates in the US quadrupled in the 1960s. The “scientific consensus” said that big government will reduce poverty, yet the higher the taxes are and the more incentives is given to the poor to have large families, the more poverty there is. And of course the “experts” also worried about “global cooling” in the 1970s.
The experts have a pretty bad track record, especially when it comes to politically sensitive things.
5. Socialism
Socialism has always been marketed as rule by the scientists and experts. Everybody shall lose their “bourgeous” human rights like right to property and freedom of association (freedom of association is racist anyway, right?) and submit to “expert rule” because the experts know it all and know it better than us rednecks. Well, not only have the “experts” been very often wrong, the centralized rule from above by the experts has proven to be a bigger disaster than any global warming scenario. (Yes, you read that correctly.)
Russia has always been a traditional food exporter and was turned into country where millions starve by the “experts”. And famine and widespread starvation has been the hallmark of socialism almost everywhere it has been tried: China, Cambodia, many african countries, etc.
The “experts” seem to be able to turn a fertile country into a desert not only much faster than global warming, but also repeatedly and in the real word (not just in a computer simulation). Warming may force a change of crops and maybe even a reduction in yield (that's a big “may” - far more likely is that it increases yields because warmer was usually better in the past) but there is no land on earth that cannot be utterly ruined by the advice of an “expert”.
When the “experts” want to create
And: the increased precipitation, snow and rain, is further diluting the surface salinity in the North Atlantic. When it gets low enough, the Gulf Stream stops its current pattern of flowing north evaporating as it goes until it's salty enough to dive to the bottom and return deep. Much change occurs worldwide, but most immediately Europe gets colder and dryer.
That's going to be very hard to ignore, and IMHO will most likely be the turning point in public and policy-making consciousness of climate change. The question is, when?
Lacking <sarcasm> tags,
"But 164 gigatonnes of glacial ice melt per year still sounds like a lot to me" Divide the volume of ice by the area of the oceans... 163e9 gigatons ice*1e6 grams/gigaton / (4 * 3.14 * 6.371e8**2 earth area *.70 sea area/earth area) * 100 years/century = 4.5 cm per century. Also, if this is only the melt rate not counting the snowfall or ice accumulation rate which could cut this by any amount including making it negative (sea level fall), then one could expect the net contribution to sea level rise to be even smaller. Regardless of any other issue related to global warming, the idea that this is "big" in the actual impact scale is simply being stymied by large absolute numbers which is a red herring. The *variability* in tidal fluctuations dwarfs this "correction" by orders of magnitude.
on sea level rise alone - a lot of Tuvalu is 1m above sea level. To cover it in water would require 250 years of 4mm per year, so it's not going to disappear overnight.
Bear in mind that 250 years ago there were an estimated 1.5m colonists in North America divided between British, Dutch and French colonies, the Prussians, the Holy Roman Empire, the Austro-Hungarian Empire, the Russian Empire and others were fighting the Seven Years war, the British had just gained control of Canada by capturing Montreal from the French and beginning the end of the French and Indian war, the Marathas kingdom in India was fighting (and losing to) the Afghans to their North, and George III was raised to the British throne. :)
A quarter of a millenium is a long time
Rational thought is the only true freedom
If the average global temperature increased then the average air pressure would...
It would do nothing along the lines of what you are thinking. The atmosphere is not enclosed in a rigid container (external force), but held by gravity (body force).
The average pressure at sea level is the gravitational weight of the atmosphere divided by the surface area of the earth. The classical mass of the atmosphere is independent of average temperature.
Yes, local temperature changes cause local pressure changes. This does not mean global average temperature changes cause global average pressure changes.
I think it just means that in reality, science hasn't got all the right answers, all of the time, and science should be treated, as it was always intended, with a grain of salt.
I don't think you understand what science is.
This paper is science. There is not the slightest reason to disbelief in science even the tiniest bit because one prediction has been replaced by a better prediction - because that is exactly what science is all about. Science is a highly successful method of getting ever closer to whatever the "right answer" may be, by falsification, replacement, improvement.
That real revolution in thinking has not yet made it into our ape brains. We enjoy the successes it has given us, from technology to medicine to psychology, diplomacy, social sciences, practically everything around you except sunday church and friday flirting is heavily influenced by science. But few of us have made scientific thinking our home. When was the last time you stopped yourself in a fight with your girlfriend to re-examine the facts and try to actively falsify your hypothesis about her reasons?
Our ape brains want to verify, we feel more secure if we think we are right. Science wants to falsify, to show that the model is wrong, in as much detail as possible, so we can make up a new one that is better.
Or in less individual and more social terms: Religion starts by postulating a few facts, and then killing everyone who disagrees. Science starts by postulating a few axioms, and then trying as hard as possible to show that they're wrong. On those that survive, we build more theories, again trying hard to show they're wrong.
For geeks: Science is like crypto. An untested cipher is considered weak until enough time has passed and enough people have tried breaking it that everyone else accepts that "we" as a hole don't - at least yet - know a way to do it, so for the moment it's a good cipher.
So to bring it all full circle: This is an improvement of the climate change models, and disproves them in the same way that finding a good attack on RSA breaks cryptography. It doesn't, breaking ciphers is an important part of cryptography.
Assorted stuff I do sometimes: Lemuria.org
"We have not answered every question you have. Each answer led to more questions. But perhaps now we are confused at a more sophisticated level, and about more important things."
Information theory is life. The rest is just the KL divergence.
This year we are going to see a new record low for arctic sea ice --- surpassing even the dramatic 2007 decline.
No one can say with certainty what 'might' happen...but it can be said
what has already happened with arctic sea ice extent...and you are
wrong. Arctic sea ice extent this year is greater
than it was on the same date in 2007 AND 2008.
So even if there's no climate change, it verifies climate change.
But if there's +5C change, then, by golly, global warming has been falsified! The results didn't match prediction.
In all seriousness, though, I think there's a real paradox in what we consider falsification and verification in science if the above two statements are both true.
Yes, there's a problem with what you consider falsification. Falsification applies to theories, not to observations.
If the temperature rises 5C, it would falsify the theory by which we model and predict global warming. However, the observation of global warming would be stronger than ever. So, we'd have to change our theories.
It's similar to how experiment falsified the Caloric theory of heat because the result did not match predictions, but did not falsify the concept of heat. Observations that did not match Newton's Law of Gravity did not "falsify" the observation that gravity exists.
On the other hand, a temperature change of 0 degrees, that would validate the theory by which we model and predict global warming. However the observation would be of no global warming for that period. It would be correct to say "there was no global warming in this ten year period". Just remember that unlike a theory or model, this would not "falsify" the previous observations of warming.
The enemies of Democracy are
In science, when your hypothesis is falsified by the data being different from its predictions, you abandon it and look for a different model.
In religion, when the predictions of your dogma turn out to be wrong, you tell your critics that they just don't understand how your religion works, and really with a deeper understanding you were right all along.
Supporters of the notion that "AGW is a serious threat" keep sounding like the latter case to me. When the data is unexpected, the models are adjusted to explain that too, and the modelers keep believing. Creationists have really entertaining explanations for the fossil record - but it doesn't help your case if the explanations come after the data, as that's sort of the opposite of a prediction.
If your belief in AGW (or anything else!) is scientific and not religious, then you can both explain the belief at a qualitative level (quick: how does a greenhouse work?) and you can explain what new data would cause you to abandon your belief. In my experience, most people who consider themselves intellectuals have a religious faith in scientists (the intellectually lazy approach) instead of having scientific beliefs.
Socialism: a lie told by totalitarians and believed by fools.
The problem I have with the people who believe in AGW is that mostly they fall more in the religious category, anyone who tries to present results different then there's or question the methods used is subjected to public ridicule, not listened to. This is religious reasoning, not scientific, listen to the people who disagree and adjust your methods, stop believing that everything you have done is exactly correct and I will listen to you too. There are many flaws in the methodology, from sensors placed within 10 feet of AC exhaust to sensors placed in the middle of a asphalt parking lot, these things skew the results and aren't taken into account.
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
Scientists certainly do "believe" in evolution (well, a few of them don't, I suppose) and that belief is justified by a great many successful predictions made by that theory (and not by others).
It's simply not the case that science is about adjusting the theory to fit the data (well, it happens, but it's not seen as good science). Newtons theories weren't "adjusted" by relativity, they were proven wrong. They were still useful, in fact very predictive in most cases, but nevertheless wrong.
Anyway, that whole discussion misses the point: as you say, it's not about black-or-white "right" or "wrong", its about how predictive is a hypothesis over the domain of interest. Thus far, to the extent that the climate modelers have deigned to make any predictions, the predictive value of those models has been crap. Call it "right" or "wrong", I don't care, but I call it "not sufficiently predictive to justify telling me what to do in my daily life"!
And what about you - sarhjinian - are your beliefs about AGW scientific or religious? Do you actually understand what you're arguing for, or are you just saying "I'm part of the 'in' crowd that believes in X, not one of those lossers with unfashionable beliefs".
Quick: how does a greenhouse work? Are we in an ice age right now? What's the only 10ky period of relatively stable climate in the past 400K years, per the accurate ice core data - is a stable climate norma? What's the obvious ~100ky cycle in that data? What's the highest historical level of CO2 (as a multiple of today's) since the oxygen catastrophe? How well did life on land do during that time?
Well, have you actually taght yourself about this stuff, or are you just fashionable?
Socialism: a lie told by totalitarians and believed by fools.