Introduction - Models are not All Wet: Models, Water and Temperature (2)
Introduction - Models are not All Wet: Models, Water and Temperature (2)
I am starting a series of blogs on models, water, and temperature.
A couple of entries ago, I wrote a somewhat muddled blog, Difference Between Night and Day. My major goal in that blog was to look at how water, especially water vapor, enters into the climate and climate change problem. I used some regional differences in climate, say Florida's and Arizona's, with the hope of suggesting that we have some intuition of how water vapor modifies regional climate. For example, due to the absence of water vapor, Arizona's extremes of daily temperature are larger than in a much wetter Florida.
This simple intuitive notion, however, quickly falls into complexity. It is the typical complexity of climate science, where the members of a set of simple physical processes combine in many different ways to produce a difficult-to-untangle knot of observations. I will come back to this later, but first, here are some of the other ideas I had in mind in that first blog.
At the end of that blog I referred to the paper by Kukla and Karl, 1993, Nighttime Warming and the Greenhouse Effect (from Rood’s Class Website). This paper investigates the observed decrease in the range between nighttime lows and daytime highs. At the writing of that paper in 1993, the models of 20 years ago did not simulate this observation especially well. How does one respond to fact that models don’t represent a particular observation? A common way to respond, sometimes put forward by commenters on this blog, is that the models fail to represent the observations; hence, the model is wrong, and to base any conclusions, actions or behavior on model results is grievous failure of reason.
I, of course, reject this conclusion. When I get the result that the model does not represent an observation especially well, then I take this as a piece of information that motivates further investigation. The scientific investigations of my career have been based on the process that we develop a model from a set of physical laws that are expressed as mathematical expressions. The physical laws and the construction of the original model are based in their most fundamental way on observations. If the model has been developed properly, then it offers an approximation of that observed behavior. If this is the case, then we have an experimental tool that can be used for further investigation. That investigation is motivated both by the shortcomings in the model’s ability to represent observations we already have and by new observations that come along. In this approach models evolve as a tool that help us explore and manage the complexity of the climate system. They also help guide our thinking about the future based on the projections that come from the models. Models are, therefore, devices to help us think; they do not provide the answer.
Another idea that I introduced in the Difference Between Night and Day was that large changes in the amount of water at the surface, for example, the Dust Bowl and irrigation in the Corn Belt, might have significant regional impacts on climate. The place I am going with this, ultimately, is the Midwest Warming Hole (2 MB if you click), and that requires thinking about water. The Midwest Warming Hole is an observed feature in the center of the United States that is not warming up as fast as the regions around it or as fast as the models predict. This is not a newly discovered feature, but it is a feature that I think takes on new interest as we think about this hot summer, the last hot summer, and how to use the observations today to think about the climate in the future and how to adapt to a warming climate. The Midwest Warming Hole, and the ability or inability to represent it in models, is also a great example to help people think about how to describe model uncertainty.
The last big theme that I want to follow from the original blog is the improvement of ways to discuss and understand the role of water – solid, liquid and vapor – in climate and climate change. I did a series Just Temperature ( one, two, three) which was motivated by the stunningly warm spring in 2012 in the continental United States and my thinking of extreme events as climate change case studies. The Just Temperature series used the fact that the warming of the Earth has become large enough that it is possible using temperature observations alone to make a compelling case the Earth is warming. But once we make it beyond that fact, we have to think about water to understand the complexity of both the spatial and temporal structure of the observed trends.
So here are three big themes that I want to organize around:
1) Doing science with models
2) Communicating the role of water in climate and climate change
3) Thinking about changes in land use and its impacts on water
These will be interspersed, of course, with some tangents to interesting subjects here and there. But those who know this blog know that eventually I get there.
r
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Anyway, speaking of Watts, a few weeks ago he had a breathless entry asking, "Coldest July in history for Anchorage?", explaining that month-to-date, the city was on its way to a record cold month.
Not so fast there, silly boy.
The average temperature so far this month in Anchorage has been 55.4 degrees. That's a full degree higher than the coldest July ever there (in 1920). If the official forecast for the last two days of the month pans out, Anchorage will end with a July average temperature of 55.6 degrees. Given that the July average for 2008 was 55.4, I wonder whether Watts will again suspend his vacation plans, only this time to loudly and breathlessly announce "Coldest July in four years for Anchorage!"
Nah, he'll be too busy trying to get his "paper" published. Is Comic Book Connoisseur still in publication? Inquiring skeptics want to know!!
Well, AW wanted blog reviews, they've started.
The Stoat is underwhelmed:
"So whatever it was had to be major, and it had to be timely. How thrilling! But, sigh, we are doomed to be disappointed: its just a paper preprint. All over the world scientists produce draft papers and send them off for peer review. Only dramah queens pimp them up like this. And what exactly was the urgency? Watts could easily have stuck the thing in an envelope to whatever journal, gone quietly off on holiday, and done the PR schitck when he came back. So all this tripe about “not something I can miss now and do later” is just tripe.
Notice, BTW, that they haven’t even said where its going to be submitted. Which means that either they don’t know – which is crap – or they do know, but are embarrassed to say, because of the smallness of the journal. I suspect the latter."
Dr. Victor Venema posts at the Stoat's:
"As far as I can see the main novelty is that the weather station classification scheme of Leroy (2010) is better than Leroy (1999). It would have been more elegant if Watts had stated in his press release that the differences between stations of various qualities he found in the temperature trends are only visible in the raw data and not in the homogenized (adjusted) data."
Link to Stoat.
More from Dr. Venema Link
07-27-2012 10:52 BJT The platform will be based at the Shanghai Environment and Energy Exchange. The trials will involve 200 firms in 16 industries, such as steel, petrochemicals, non-ferrous metals, and power and six non-industrial fields, such as airlines, ports, airports and hotels.
Scientists say these kinds of companies are responsible for approximately 110 million tons of carbon dioxide emissions a year, or nearly half of the city’s annual emissions.
Zheng Dawei, head of Investment Banking Dept.,SPD Bank, said, "Carbon emissions trading treats carbon credits as merchandise that can be bought and sold. The companies will first be given initial quotas for carbon emissions for free, by Shanghai’s NDRC. The quotas are based on their historical emissions data. Any surplus or shortage of credits can be adjusted through transactions in the carbon credit market. "
Zheng says it’s imperative for China to establish a national carbon emissions trading market and then to join international efforts. China’s involvement in the international carbon market now is mostly through what’s known as the CDM, or Clean Development Mechanism. The way it works is that developed countries get a carbon reduction credit by investing in clean energy projects. But the CDM faces an uncertain future.
Zheng said, "The Kyoto Protocol, the international treaty to combat climate change, gave birth to the CDM. However, the first phase of the protocol is due to expire at the end of this year. I think that’s also one of the reasons why China has to start its own carbon market next year. "
Beyond Shanghai, six other cities and provinces, Beijing, Tianjin, Shenzhen, Chongqing, and Guangdong and Hubei Provinces will be involved in the pilot project. And if all goes well, a nationwide system is scheduled to be in place by 2015. Zheng says that’s expected to help the national goal of a 17 percent reduction in carbon intensity by 2015.
Complete waste of time.
By Environment Correspondent Alister Doyle
OSLO | Fri Jul 27, 2012 7:53pm IST
(Reuters) - Scientists are finding evidence that man-made climate change has raised the risks of individual weather events, such as floods or heatwaves, marking a big step towards pinpointing local costs and ways to adapt to freak conditions.
"We're seeing a great deal of progress in attributing a human fingerprint to the probability of particular events or series of events," said Christopher Field, co-chairman of a U.N. report due in 2014 about the impacts of climate change.
Experts have long blamed a build-up of greenhouse gas emissions for raising worldwide temperatures and causing desertification, floods, droughts, heatwaves, more powerful storms and rising sea levels.
But until recently they have said that naturally very hot, wet, cold, dry or windy weather might explain any single extreme event, like the current drought in the United States or a rare melt of ice in Greenland in July.
But for some extremes, that is now changing.
A study this month, for instance, showed that greenhouse gas emissions had raised the chances of the severe heatwave in Texas in 2011 and unusual heat in Britain in late 2011. Other studies of extremes are under way.
Growing evidence that the dice are loaded towards ever more severe local weather may make it easier for experts to explain global warming to the public, pin down costs and guide investments in everything from roads to flood defenses.
"One of the ironies of climate change is that we have more papers published on the costs of climate change in 2100 than we have published on the costs today. I think that is ridiculous," said Myles Allen, head of climate research at Oxford University's Environmental Change Institute.
"We can't (work out current costs) without being able to make the link to extreme weather," he said. "And once you've worked out how much it costs that raises the question of who is going to pay."
Industrialized nations agree they should take the lead in cutting emissions since they have burnt fossil fuels, which release greenhouse gases, since the Industrial Revolution. But they oppose the idea of liability for damage.
Almost 200 nations have agreed to work out a new deal by the end of 2015 to combat climate change, after repeated setbacks. China, the United States and India are now the top national emitters of greenhouse gases.
Field, Professor of Biology and Environmental Earth System Science at the University of Stanford, said that the goal was to carry out studies of extreme weather events almost immediately after they happen, helping expose the risks.
"Everybody who needs to make decisions about the future - things like building codes, infrastructure planning, insurance - can take advantage of the fact that the risks are changing but we have a lot of influence over what those risks are."
FLOODS
Another report last year indicated that floods 12 years ago in Britain - among the countries most easily studied because of it has long records - were made more likely by warming. And climate shifts also reduced the risks of flooding in 2001.
Previously, the European heatwave of 2003 that killed perhaps 70,000 people was the only extreme where scientists had discerned a human fingerprint. In 2004, they said that global warming had at least doubled the risks of such unusual heat.
The new statistical reviews are difficult because they have to tease out the impact of greenhouse gases from natural variations, such as periodic El Nino warmings of the Pacific, sun-dimming volcanic dust or shifts in the sun's output.
So far, extreme heat is the easiest to link to global warming after a research initiative led by the U.S. National Oceanic and Atmospheric Administration and the British Meteorological Office.
"Heatwaves are easier to attribute than heavy rainfall, and drought is very difficult given evidence for large droughts in the past," said Gabriele Hegerl of the University of Edinburgh.
Scientists often liken climate change to loading dice to get more sixes, or a baseball player on steroids who hits more home runs. That is now going to the local from the global scale.
Field said climate science would always include doubt since weather is chaotic. It is not as certain as physics, where scientists could this month express 99.999 percent certainty they had detected the Higgs boson elementary particle.
"This new attribution science is showing the power of our understanding, but it also illustrates where the limits are," he said.
A report by Field's U.N. group last year showed that more weather extremes that can be linked to greenhouse warming, such as the number of high temperature extremes and the fact that the rising fraction of rainfall falls in downpours.
But scientists warn against going too far in blaming climate change for extreme events.
Unprecedented floods in Thailand last year, for instance, that caused $45 billion in damage according to a World Bank estimate, were caused by people hemming in rivers and raising water levels rather than by climate change, a study showed.
"We have to be a bit cautious about blaming it all on climate change," Peter Stott, head of climate monitoring and attribution at the Met Office's Hadley Centre, said of extremes in 2012.
Taken together, many extremes are a sign of overall change.
"If you look all over the world, we have a great disastrous drought in North America ... you have the same situation in the Mediterranean... If you look at all the extremes together you can say that these are indicators of global warming," said Friedrich-Wilhelm Gerstengabe, a professor at the Potsdam Institute for Climate Impact Research.
(Additional reporting by Sara Ledwith in London; Editing by Louise Ireland)
Good to hear you say that. I'm glad it wasn't just me... ;-)
I had to chuckle at the "crowd sourcing" part of the press release...surely that is the highest standard in scientific research, right?
ScienceDaily.com
The chronic drought that hit western North America from 2000 to 2004 left dying forests and depleted river basins in its wake and was the strongest in 800 years, scientists have concluded, but they say those conditions will become the "new normal" for most of the coming century.
Such climatic extremes have increased as a result of global warming, a group of 10 researchers reported July 29 in Nature Geoscience. And as bad as conditions were during the 2000-04 drought, they may eventually be seen as the good old days.
ClimateCentral.org
Well, I'm not even close to an expert. However, I read the paper and it appeared to me that Watts was comparing the raw data with the adjusted data and coming up with, well, what he wanted. I've read some of the reactions of those who *are* experts and it appears that I've got the point, even if a lot of the details escape me. It is what Tamino calls "mathturbation."
Still, Watts now admits to 50% of the warming that real scientists have found. That makes him half-something. (I'll leave the "something" to be defined by the reader's sensibilities and familiarity).
This is what absolutely terrifies me. Drought is about the worst possible consequence, imo.
I'm tempted to say "cool", but somehow that doesn't seem to fit. It's a very striking piece of work.
Grist.org
I meet Tom Swetnam, director of the laboratory of tree-ring research at the University of Arizona in Tucson, on a Sunday morning because he’s leaving for Siberia in a few days and is otherwise totally booked. As part of the paleofire team that will be traveling to the “Alaska of Siberia, if you will” to study fire and climate, Swetnam will spend a few weeks immersed in the burn history — and possible future — of some of the largest forests on Earth.
“We’re trying to understand fire, climate change, and carbon emissions out of Siberia because of the huge carbon pool contained there in the soil, permafrost, bogs, and forests,” says Swetnam, a sturdy middle-aged man with an outdoorsy white beard. “This giant pool of carbon is beginning to burn in a massive way — the amount of area burning in Siberia is startling.”
Anybody, that has taken basic statistics would know that this sample is far to small to have any validity.
"Scientist say" what scientist? site your sources.
Also, 97% of Climate scientist. Really, did you really think that I would not know that those stats are loaded to one side.
But, good work. There are plenty of people out there that will take your for what you say.
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