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Global Warming Since 1997 Underestimated By Half
Layzej writes "A new paper shows that global temperature rise of the past 15 years has been greatly underestimated. The reason is that the weather station network covers only about 85% of the planet. Satellite data shows that the parts of the Earth that are not covered by the surface station network, especially the Arctic, have warmed exceptionally fast over the last 15 years. Most temperature reconstructions simply omit any region not covered. A temperature reconstruction developed by NASA somewhat addresses the gaps by filling in missing data using temperatures from the nearest available observations. Now Kevin Cowtan (University of York) and Robert Way (University of Ottawa) have developed a new method to fill the data gaps using satellite data. The researchers describe their methods and findings in this YouTube video. 'The most important part of our work was testing the skill of each of these approaches in reconstructing unobserved temperatures. To do this we took the observed data and further reduced the coverage by setting aside some of the observations. We then reconstructed the global temperatures using each method in turn. Finally, we compared the reconstructed temperatures to the observed temperatures where they are available... While infilling works well over the oceans, the hybrid model works particularly well at restoring temperatures in the vicinity of the unobserved regions.' The authors note that 'While short term trends are generally treated with a suitable level of caution by specialists in the field, they feature significantly in the public discourse on climate change.'"
Clearly they have a cooling effect.
Give me Classic Slashdot or give me death!
The first link in the summary links to the paper published by the Journal of the Royal Meteorological Society.. The youtube video makes the science accessible to the layman.
No no no. You don't understand. *this* time we got it right.
Fail.
Cowtan and Way circumvent both problems by using an established geostatistical interpolation method called kriging – but they do not apply it to the temperature data itself (which would be similar to what GISS does), but to the difference between satellite and ground data. So they produce a hybrid temperature field. This consists of the surface data where they exist. But in the data gaps, it consists of satellite data that have been converted to near-surface temperatures, where the difference between the two is determined by a kriging interpolation from the edges. As this is redone for each new month, a possible drift of the satellite data is no longer an issue.
Prerequisite for success is, of course, that this difference is sufficiently smooth, i.e. has no strong small-scale structure. This can be tested on artificially generated data gaps, in places where one knows the actual surface temperature values but holds them back in the calculation. Cowtan and Way perform extensive validation tests, which demonstrate that their hybrid method provides significantly better results than a normal interpolation on the surface data as done by GISS.
The only thing in TFS is that they cover 85% of the globe, where does the "half" come from?
From the paper, which actually found 2.5 times as much warming by leveraging satellite data as the CRUtemp does by ignoring the unobserved region. The paper shows that the Arctic is warming at about eight times the pace of the rest of the planet. This is not an unexpected finding: see polar amplification
You be trolling ma'am. You toss off an overstated, inflammatory reply - that's trolling.
Yes, it's also factually incorrect. But that's life.
Faster! Faster! Faster would be better!
If a doctor tells me I have cancer, and then later tells me it's progressing twice as fast as originally thought, of course that causes me to lose confidence in doctors and thus ignore anything they have to say. Instead, I'll go listen to the homeopathy providers who keep telling me that doctors don't know what they're talking about, and aren't always telling me that I'm going to die. After all, doctors are only interested in making money.
Wait, there's a debate about whether or not the climate is warming? That's news to me. There's certainly a debate about exactly how quickly it's rising, which is something the scientists have not expressed certainty about. But the fact that the planet is warming as well as the question of the main cause very well studied, well demonstrated and not heavily debated among scientists.
Science really isn't about confidence. It's about evidence. If holding the line, even when you know you're wrong, is what makes people feel confident, it's no wonder they turn to religion. But I'm personally thankful that at least one discipline isn't afraid to publish results that contradict earlier findings, if that's where the evidence leads.
As someone who understands this process, findings like this lend tremendous credibility to the scientific community, and yes, boost my confidence in the work they're doing and the integrity of the published results. It's what makes science the best method we know of for understanding reality.
I admit, it's a bit off topic, but it is something that has bugged me for ages and I still didn't find an answer, so please, maybe someone can shed some light on it:
Why is there a "controversy" about Global Warming, and why is there none about "Terrorism"?
Global Warming may or may not happen. Ok. I don't want to discuss what kind of "proof" one side or the other may have, let's just say it may or may not happen. Likewise, terrorism. There may or may not be terrorist attacks on some parts of "our" (with varying definitions of "our") soil. Again, I don't want to discuss whether or not they would happen.
The point now is: We try to do anything in our power to prevent terrorist attacks, while at the same time we argue whether or not we should do anything to prevent Global Warming. My question is: From a risk management point of view, shouldn't it be the other way 'round?
Both are classic examples of Risk Management problems. Risk and cost to mitigate vs. reward/damage contained. It's the usual 2x2 matrix. On X, we have "do nothing" and "do something", on Y we have "nothing happens" and "something happens" (ok, very simplified, but you get the idea). So, in case of terrorism, that would net us:
We don't do anything and nothing happens: Pre-9/11 situation, no cost, perfect situation
We do prepare and nothing happens: Possibly the current situation, high cost and no damage
We prepare and an attack happens: Also the possibly current situation, high cost but with good damage control, leading to no/little damage
We don't prepare and an attack happens: Worst case scenario, no cost to prepare but high damages, possibly costing thousands of lives.
When you do the same matrix for Global Warming, it looks quite similar, though with a teeny-tiny little twist at the end:
We don't do anything and nothing happens: Current situation and best case future scenario
We do prepare and nothing happens: High cost, potential change in our lifestyle for no gain.
We prepare and an attack happens: Also high cost, but climate changes can be mitigated to the point where only little/no damage has to be suffered.
We don't prepare and an attack happens: Worst case scenario, with millions on coastlines being dead or homeless, with out of control storms and the weather from hell.
The thing I have problems with now is: The former can, worst case, cost a few thousand lives with maybe a building or two gone. The latter can literally cost millions of lives with coastal areas becoming uninhabitable for decades, if not forever, with storms causing damages in the billions and unforeseeable effects to agriculture and nature (and of course tourism, but I guess that's the least of our concerns then). And we're not talking about some brown bodies being killed, that could well be millions of AMERICANS dead, so the usual "Anyone outside the US doesn't count as human to the US" won't apply.
Yet we pump billions into the defense against terrorism, but we keep bickering on whether or not Global Warming may or may not happen. Anyone able to explain the sense in that?
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Uhh, is it me or do folks really not know how to read basic charts? Yes, the temperature changes due to cycling glacial periods are real. They are also spread out across vast chunks of time; the rate of these cyclic background climate changes are very, very, very slow.
Not guilty, your Honor! Death is a natural cycle; he was dying before I ever met him! The bullets I shot into him had nothing to do with it.
Everything is better with chainsaws.
Sigh, +4 Insightful.
Are you a climatologist? Your keep making these accusations without any references, citations... What exactly makes you so sure the experts are wrong?
On the one hand we have these publically funded (and therefore to some extent accountable) scientists saying that, yes, there is very likely an enormous problem. On the other hand we have privately funded "thinktanks" like Heartland and some flaky websites saying, variously (and sometimes simultaneously)
-- AGW is not happening.
-- AGW may be happening but there's nothing we can do about it.
-- AGW is happening but we should not try to do anything about it because the suggested courses of action are just Marxist plots to sap and impurify our precious bodily bodily fluids.
Gosh, thanks. That must be why the other ships call me Meatfucker -- GCU Grey Area (Eccentric)
Why do you think the IPCC no longer uses the Hockey-stick graph?
They don't use Mann's original hockey stick graph from 1998 any more because it's 15 years old and numerous other newer reconstructions have been done since then. But if you take a look at Chapter 5 - "Information from Paleoclimate Archives" of the IPCC AR5 - WG I report you'll find that figures 5.7 & 5.8 still look remarkably like the original hockey stick graph. So they've got newer versions of it.
It was autumn, and the Indians on the remote reservation asked their new Chief if the winter was going to be cold or mild. Since he was an Indian Chief in a modern society, he had never been taught the old secrets, and when he looked at the sky, he couldn't tell what the weather was going to be. Nevertheless, to be on the safe side, he replied to his tribe that the winter was indeed going to be cold and that the members of the village should collect wood to be prepared. But also being a practical leader, after several days he got an idea. He went to the phone booth, called the National Weather Service and asked, "Is the coming winter going to be cold?" "It looks like this winter is going to be quite cold indeed," the meteorologist at the weather service responded. So the Chief went back to his people and told them to collect even more wood in order to be prepared. One week later he called the National Weather Service again. "Is it going to be a very cold winter?" "Yes," the man at National Weather Service again replied, "it's going to be a very cold winter." The Chief again went back to his people and ordered them to collect every scrap of wood they could find. Two weeks later he called the National Weather Service again. "Are you absolutely sure that the winter is going to be very cold?" "Absolutely," the man replied. "It's going to be one of the coldest winters ever." "How can you be so sure?" the Chief asked. The weather man replied, "The Indians are collecting wood like crazy."
In most cases I would agree. The problem here is that, if the vast majority of climatologists are even remotely on the right track, we do not have the luxury of "sitting back" until things settle down.
I guess for me it boils down to this: if there is a nonzero probability X that future generations will suffer devastating consequences of our pollution, we should do everything we can to mitigate that. This is true even for small X because the scale of consequences are potentially very large.
But more to the point, even though you are right that this science is new, I put more value on the statements of experts in the field, rather than some random person on the Interwebs who, for all I know, just refuses to take it seriously because the implications might inconvenience her slightly.
The energy captured in coal, gas and oil is the result of many millions of years of sunshine. I just can't reasonably expect there to be no significant effects to our releasing that in a matter of a few decades.
Gosh, thanks. That must be why the other ships call me Meatfucker -- GCU Grey Area (Eccentric)
Careful, some might accuse you of crisis mongering.
Yes, and others stand accused of crisis whitewashing. What is your point?
Vague declarations of doom are not a rational basis on which to surrender all of one's economic freedom and much of one's standard of living.
I wouldn't call the IPCC reports "vague declarations of doom". They are quite concrete declarations of doom. There is a bit of a spectrum of options between fingers-in-ears and surrendering all economic freedom (whatever that means) and standard of living -- unless perhaps you're Koch, BP, and so on.
Some people just can't stop looking for a Messiah, a Prophet to simultaneously fill them with fear and then promise to deliver them from that fear.
You invoke an image of some sectarian cult. This is not an accurate description of the position of a large majority of climate scientists. Sure, it is a relatively young field. But that's still better, warts and all, than no science. Not to mention the anti-science punted by vested interests.
Gosh, thanks. That must be why the other ships call me Meatfucker -- GCU Grey Area (Eccentric)