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Sue Ogrocki / AP
In this Sept. 30, 2011, file photo, sailboats and a floating dock lie on the dry, cracked dirt in a harbor at Lake Hefner in Oklahoma City as drought continues to be a problem across the state. The relentless type of heat that has blistered the U.S. and other parts of the world in recent years is due to man-made global warming, a new study from a top government scientist says.
The relentless, weather-gone-crazy type of heat that has blistered the United States and other parts of the world in recent years is so rare that it can't be anything but man-made global warming, says a new statistical analysis from a top government scientist.
The research by a man often called the "godfather of global warming" says that the likelihood of such temperatures occurring from the 1950s through the 1980s was rarer than 1 in 300. Now, the odds are closer to 1 in 10, according to the study by NASA scientist James Hansen. He says that statistically what's happening is not random or normal, but pure and simple climate change.
"This is not some scientific theory. We are now experiencing scientific fact," Hansen told The Associated Press in an interview.
Hansen is a scientist at NASA's Goddard Institute for Space Studies in New York and a professor at Columbia University. He has called for government action to curb greenhouse gases for years. While his study was published online Saturday in the Proceedings of the National Academy of Science, it is unlikely to sway opinion among the remaining climate change skeptics.
However, several climate scientists praised the new work.
In a departure from most climate research, Hansen's study — based on statistics, not the more typical climate modeling — blames these three heat waves purely on global warming:
—Last year's devastating Texas-Oklahoma drought.
—The 2010 heat waves in Russia and the Middle East, which led to thousands of deaths.
—The 2003 European heat wave blamed for tens of thousands of deaths, especially among the elderly in France.
The analysis was written before the current drought and record-breaking temperatures that have seared much of the United States this year. But Hansen believes this too is another prime example of global warming at its worst.
In an opinion column published Saturday in The Washington Post, Hansen said his predictions in the late 1980s of the dire consequences of steadily increasing temperatures have proven to be worse than he thought.
“Our analysis shows that it is no longer enough to say that global warming will increase the likelihood of extreme weather and to repeat the caveat that no individual weather event can be directly linked to climate change. To the contrary, our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.
The deadly European heat wave of 2003, the fiery Russian heat wave of 2010 and catastrophic droughts in Texas and Oklahoma last year can each be attributed to climate change. And once the data are gathered in a few weeks’ time, it’s likely that the same will be true for the extremely hot summer the United States is suffering through right now.
These weather events are not simply an example of what climate change could bring. They are caused by climate change. The odds that natural variability created these extremes are minuscule, vanishingly small. To count on those odds would be like quitting your job and playing the lottery every morning to pay the bills."
The new research makes the case for the severity of global warming in a different way than most scientific studies and uses simple math instead of relying on complex climate models or an understanding of atmospheric physics. It also doesn't bother with the usual caveats about individual weather events having numerous causes.
The increase in the chance of extreme heat, drought and heavy downpours in certain regions is so huge that scientists should stop hemming and hawing, Hansen said. "This is happening often enough, over a big enough area that people can see it happening," he said.
Scientists have generally responded that it's impossible to say whether single events are caused by global warming, because of the influence of natural weather variability.
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However, that position has been shifting in recent months, as other studies too have concluded climate change is happening right before our eyes.
Hansen hopes his new study will shift people's thinking about climate change and goad governments into action. He wrote an op-ed piece that appeared online Friday in the Washington Post.
"There is still time to act and avoid a worsening climate, but we are wasting precious time," he wrote.
The science in Hansen's study is excellent "and reframes the question," said Andrew Weaver, a climate scientist at the University of Victoria in British Columbia who was a member of the Nobel Prize-winning international panel of climate scientists that issued a series of reports on global warming.
"Rather than say, 'Is this because of climate change?' That's the wrong question. What you can say is, 'How likely is this to have occurred with the absence of global warming?' It's so extraordinarily unlikely that it has to be due to global warming," Weaver said.
For years scientists have run complex computer models using combinations of various factors to see how likely a weather event would happen without global warming and with it. About 25 different aspects of climate change have been formally attributed to man-made greenhouse gases in dozens of formal studies. But these are generally broad and non-specific, such as more heat waves in some regions and heavy rainfall in others.
Another upcoming study by Kevin Trenberth, climate analysis chief at the National Center for Atmospheric Research, links the 2010 Russian heat wave to global warming by looking at the underlying weather that caused the heat wave. He called Hansen's paper an important one that helps communicate the problem.
But there is bound to be continued disagreement. Previous studies had been unable to link the two, and one by the National Oceanic and Atmospheric Administration concluded that the Russian drought, which also led to devastating wildfires, was not related to global warming.
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White House science adviser John Holdren praised the paper's findings in a statement. But he also said it is true that scientists can't blame single events on global warming: "This work, which finds that extremely hot summers are over 10 times more common than they used to be, reinforces many other lines of evidence showing that climate change is occurring and that it is harmful."
Skeptical scientist John Christy of the University of Alabama at Huntsville said Hansen shouldn't have compared recent years to the 1950s-1980s time period because he said that was a quiet time for extremes.
But Derek Arndt, director of climate monitoring for the federal government's National Climatic Data Center, said that range is a fair one and often used because it is the "golden era" for good statistics.
Granger Morgan, head of engineering and public policy at Carnegie Mellon University, called Hansen's study "an important next step in what I expect will be a growing set of statistically-based arguments."
In a landmark 1988 study, Hansen predicted that if greenhouse gas emissions continue, which they have, Washington, D.C., would have about nine days each year of 95 degrees or warmer in the decade of the 2010s. So far this year, with about four more weeks of summer, the city has had 23 days with 95 degrees or hotter temperatures.
Hansen says now he underestimated how bad things would get.
And while he hopes this will spur action including a tax on the burning of fossil fuels, which emit carbon dioxide, a key greenhouse gas, others doubt it.
Science policy expert Roger Pielke Jr. of the University of Colorado said Hansen clearly doesn't understand social science, thinking a study like his could spur action. Just because people understand a fact that doesn't mean people will act on it, he said.
In an email, he wrote: "Hansen is pursuing a deeply flawed model of policy change, one that will prove ineffectual and with its most lasting consequence a further politicization of climate science (if that is possible!)."
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Once again for all the assorted warblers of "Wish Physics", like "economykiller" and "SaneScientist", let's go over the action of CO2 and the source of its potency as a green house gas when compared to other more common species like H2O.
The effectiveness of the various green house gases to trap heat even in small concentrations arises from the fact that they selectively intercept disjoint regions of the solar spectrum.
Because the Sun is hotter (5525K) than the Earth (300K), the incoming (black body) radiation energy is strongly concentrated in visible light. Visible light is visible because if you are a successful organism evolving photo-receptors for this planet, then you will win if you can see where the illumination is strongest. Now because the Earth is far cooler than the Sun, when the Earth cools its (black body} radiation energy is strongly concentrated in infra-red light. "Green house gas" molecules have a great affinity for the capture of infra-red light, so large chunks of the outgoing radiative energy are now stopped in the green house gas. If this heat was only kept in the green house gas, there would not be much of an effect on our heat balance.
However the heat captured by the green house gas molecule, is then shared by collisions with all the other gases in the air. That process is not reversible directly, and the loss of heat back into space depends on the quasi black body radiative transfer from the atmosphere as a whole. Since CO2 is such a strong absorber in spectral regions (10.2 - 11 µm) different from H2O and since the H2O concentration is largely fixed by the general thermal equilibrium of air and water on the planet, the CO2 (and also CH4) species are the sensitive drivers of net heat balance. Encroaching on the only spectral window left to let the heat escape at night.
So, if you imagine that the heat capacity of only the green house gas stored the captured heat, then for sure that wouldn't amount to squat, but that picture is completely false. The core of the problem is US, because we are amplifying a natural warming trend. Hansen and other serious thinkers are worried because of the rate of this change, not the notion that this warming is somehow unique.
The common Wish Physics arguments, pushed by Oil Shills like the Koch crowd, just fail, nobody in the professional climate science community is lying to you. The situation is very similar to the actions of those unscrupulous folks who took (and likely still take) the tobacco companies money to lie to us about lung cancer.
The common pride of ignorance among climate science deniers is the real lie here, it only serves to perpetuate the problem and to dilute everyone's courage to examine the proper extent to which we should try and mitigate the AGW problem.
You are forgetting about both atmospheric convection of heat from lower to upper atmosphere and the cooling action of CO2 in the upper atmosphere, as well as the action of heated CO2 molecules in atmospheric expansion and resultant cooling that follows from adiabatic expansion (as opposed to adiabatic compression that contributes to heating of the massive lower atmosphere on Venus).
I just wanted to remind you of these for the general public. You would do well not to ignore such factors in the climate equation as many do.
Many climate scientists and their "sheep" ignore such things but they should not be ignored, especially since atmospheric temperatures a couple years ago were reportedly 1.5 degrees C lower than expected by a number of predictive algorithms for the current time.
dcpyle ... what, sir, are you smoking?
Convection pretty much stops at the boundary of the troposphere, certainly is absent above the stratosphere, so while these transport fluxes are in play locally, even regionally, they just don't compete with global radiation transport. As for all this alleged adiabatic expansion and compression, you'll have to tell us how that actually moves and heat into space. I think all it can do is slosh the heat around. Finally, please explain this magic "cooling action of CO2 in the upper atmosphere". Whatever that piece of "Wish Physics" might be, the concentration of CO2 drops very fast with altitude, while the molecule to molecule interaction rates drop with the square of the concentration leading to a much weaker effect from anything dependent of the concentration of CO2.
I would welcome some citations from refereed literature supporting these peculiar arguments.
Typical religionist, lib response--sling an insult at a person who writes or says something you don't comprehend fully.
Most of what I have written in the post to which you replied is fundamentally covered in Physics 101 and Earth Science 101. Many climate scientists and their sheep have forgotten the basics, it would appear.
Cooling of mesosphere (stratosphere is in mesosphere) and thermosphere by rising levels of CO2 and CH4 (predicted in 1989):
http://www.agu.org/pubs/crossref/1989/GL016i012p01441.shtml
Radiative cooling by CO2 and NO coupled with cooling effect in thermosphere by lower solar activity (not a referreed paper but science news nonetheless):
http://www.nasa.gov/topics/earth/features/coolingthermosphere.html
Those took all of about five seconds or less to locate. I'm not going to bother doing the rest of your research for you, with one exception below.
But, here is the thing, satellite observations show that storm clouds and other kinds of clouds raise heat above the tropopause. We know that thunder clouds and certain other kinds of clouds will stretch from the troposphere into the stratosphere, bringing their heat energy upward with them.
According to the Laws of Thermodynamics, what happens to two objects when you put a cool object next to a hot object? (Hint: Think "equilibrium"). Now, apply what you have realized to the atmosphere.
What happens to molecules of gases when heated. What do they do? Does the space between them become rarified even ever so slightly in spite of their increased collisions with one another, including expansion? Does that cause the emission of heat and allow greater escape of both molecules and dissipation of the heat that accompanies them?
In that vein, consider the following:
http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/CoolingOfAtmosphere.pdf
Apply what you have realized to the atmosphere.
Couple this activity with convection, with enhanced convection via cloud formations rising into and above the tropopause, with jet streams and other mesospheric circulations to carry this rising, heated gas across the globe.
I could go on and on. Contrary to the assertions of those who dismiss the information with a wave of the hand and forget the basics in their zeal to promote their new world religion, it is not wish physics.
On the other hand, using fudge factors to connect unconnectable climate dots as well as exaggeration factors in the mathematics involved in their postulations is a form of "wish physics."
Compare IPCC predictions with observations:
http://clivebest.com/blog/wp-content/uploads/2011/06/directcomparison.png
And, so what if this graphic comes from a blog. Run the fricken numbers for yourself and see for yourself that the graphic is accurate enough to see the gist of what has been going on. Be sure to use untainted (meaning "free from fudge factors") data, though. :-)
Well this is finally interesting. Let me grant for the moment the proposition that a fair fraction of the free enthalpy in the troposphere is indeed convected to high altitude where the gas cools to the ambient temperature. Where does that heat go after that? The earth cannot shed heat into space via convection or conduction as the atmosphere thins out, it must leave via radiation. As an isolated rock we are literally in a "thermos bottle"!
Now my previous objection still stands. Even if various trace gases (and other primary gases even) get up to the higher altitudes and get excited (at the low rates implied by the ever lower density) the radiative cooling is minimal. Why? The radiation is optically thin up there and not in equilibrium with the gas particles. The high efficiency of a black body radiator in shedding heat arises because the spectrum is filled in via many scatterings off the wings of the absorption lines and in all cases the power removed by a line or band radiator is less than the power shed by the equivalent black body spectrum. Not only that, the highest black body temperature you could see at high altitude that of the local gas, much cooler than the surface, and the heat loss is going at best like the fourth power of temperature ( T^4 ).
So I am dubious of your convection proposition.
The earth is not like a thermos bottle. Physics 201 and above, and astrophysics 101. Long wave radiation is emitted into space by planetary bodies, including ours. If that were not the case no satellite would be able to see IR leaving the surface of planetary bodies. No IR could leave earth's atmosphere, which is not the case. It does leave the atmosphere.
The upper atmosphere is cooling as predicted. Place a cooler volume of gas next to a warmer one and and both will attempt to reach thermal equilibrium via conduction or otherwise. This is still the case as air circulation and convection brings heat from the surface and "injects" it into the mesosphere. The cooling action of CO2 and NO in the mesosphere then works to bring that gas into thermal equilibrium as expansion occurs. We know that the upper atmosphere has expanded because of increased drag on satellites in LEO.
In addition to this, the gases are rarified so there are larger gaps between molecules that allow various forms of IR to radiate into space and be lost over time. As molecules spread themselves further apart a cooling results from adiabatic expansion. This happens with a periodicity that has its analogy in "breathing" in its rhythmic expansion. The fact that radiation is not in equilibrium with the motion of the gas molecules is important.
Yet, because of this the upper atmosphere is cooling as predicted as levels of CO2 and CH4 and NO rise there. The Laws of Thermodynamics show that all things move to equilibrium, meaning that the warmer will become cooler, and vice versa, until equilibrium is reached. Yet, the mesosphere continues to cool, meaning that the mesosphere will continue to function like a massive heatsink. And, heat is IR. I never said that convection is the functionary of heat loss into space. Convection occurs in the lower atmosphere to the upper atmosphere. Conduction is a functionary in the upper atmosphere, as are the larger gaps between molecules in the upper atmosphere that allows radiation to escape into space.
Yet, the programmers of the models are are not yet taking all of this into account. This is one way in which the models have gone wrong. In fact, one paper that showed increases of heat leaving the troposphere was attacked and all efforts made to discredit the scientist who wrote it because it goes against everything that they thought they knew about what was going on in the earth system in relation to clouds and climate. I do not recall the title of the paper at the moment. I think it was Dr. Roy Spencer who was the author but I am not certain at the moment. I'd have to find my papers and notes from last year to know for sure though. They are in storage at the present.
You can be dubious all you want. I would expect you to be. I would hope that you would be. That is the way of science. Of course, it goes both ways. There is room for skepticism. This is especially true when entities like the CRU and IPCC use fudge factors and exaggeration factors in their work.
Take a look at this paper to better explain a good part of what is going on in the upper atmosphere:
http://www.agu.org/journals/ABS/1992/92GL00160.shtml
Recall also that the warming effect of CO2 is enhanced by the presence of H2O vapor, the two together resulting in more of the IR spectrum being absorbed in the lower atmosphere. The upper atmosphere has considerably less of the latter so there are "larger holes" to let more radiation escape into space there, which is also part of the reason for the cooling in the upper atmosphere.
OK, I must dig around in the JGR a bit, but none of these abstracts are yakking about any major change to the global heat balance. The energy in vibrational modes, as lofted to the heights, will find its way out as radiation, but there just can't be that much in that channel.
The problem is simply this: all the convective processes will work to lower the temperature gradient across the atmosphere, but at higher elevations LTE between the gas and the IR will be weaker, this means that the T^4 cooling of a black body cannot be achieved and, even if it was, the radiative loss would be progressively lower by that T^4. Ultimately no energy leaves the planet except by radiation, and the radiation losses that are plugged by CO2 near the surface are in my view not likely to be made up via this delicate convection with line radiation pathway.
So, dc, I welcome your or somebody else's proof otherwise. I think the physics is against you here.
THE exact SAME weather conditions existed most of the 1930's
Google " The dust bowls"1930's,,, Hmm gee-whiz, No "silly global warming" back then.or Al Gore
AL GORE loves this con. He's made over $ 100 MILLION for this SCAM,
The earth goes thru cycles, up and down in temps
READ LEARN, look back thru weather historical
The climate change has been going on for 150 years, so this spans the 1930s. Odd error in thinking, there.
But to be sure, climate is the spacetime average of weather, and not every fluctuation or energy burp is to be tallied against AGW. Most climate investigators now agree that Katrina, for example, was not a measure of climate change.
Another clueless denier.
In the US global warming causes heat waves.
In England global warming causes cold weather.
http://stevengoddard.wordpress.com/2012/08/10/guardian-says-global-warming-induced-cold-is-the-new-normal/
Meanwhile the oceans around the United States are not even close to being at record warm temperatures. And since water holds more cold or heat that is much more important then a heat wave that is only in 2% of the world surface.
http://wattsupwiththat.com/2012/08/10/not-hot-ocean-sst-around-the-usa-not-anywhere-near-record-levels/
The oceans are a very effective heat sink and buffer, subject to cooling by evaporation -- a first order phase transition that tends to hold the temperature variations to minimal levels. The earth and rock and other solid matter on land cannot cool by evaporation, but are subject to the radiation based heat balance I already summarized.
You are barking up the wrong tree here.