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The past 30 years has seen more "hot" (orange), "very hot" (red) and "extremely hot" (brown) summers, compared to a base period defined in this study from 1951 to 1980  (Source: NASA/Goddard Space Flight Center Scientific Visualization Studio)
Hotter summers have become the norm from 1980 to present compared to 1951 to 1980 (the base period)

NASA researchers have claimed to find new evidence for everyone's favorite topic: global warming
James Hansen, study leader from NASA's Goddard Institute for Space Studies (GISS), as well as GISS researchers Makiko Sato and Reto Ruedy, have concluded that summer heat waves (mainly in the U.S. Midwest) have become the norm over the last 30 years compared to a base period 30 years before 1980 -- and it's because of global warming. 
Their study works like this: the team collected mean summer temperatures from 1951 to 1980. This was considered the base period for the study. They then looked at the surface temperature data from the last 30 years (1980 until now) to determine whether extreme heat events were increasing. 
From there, the team wanted to see how much heating and cooling occurred in both time periods. To do this, they used a bell curve, which is a common tool that places the middle ground at the top of the bell (for instance, if this were a grading curve, a "C" would be at the top while the next tier down on each side would be a "B" and a "D," and the bottom of the bell would be an "A" and an "F). In this case, the top of the bell would be mean temperature, the next tier down would be "cold" on one side and "hot" on the other, then "very cold" and "extremely cold" on one side moving down while "very hot" and "extremely hot" are moving down the bell on the other side. 
Researchers then applied mean temperatures from 1980 until present, and found that 1980s, 1990s and 2000s fell more to the hot side than cold. The curve widened and flattened as well, which means there was a broader range of variability. This is important because Hansen once predicted that global warming's connection to extreme events would become more apparent in the decades from 1980 to present, but natural variability can play a role too and actually mask the trend. It was important to distinguish the two. 
This wider curve created the new "extremely hot" category, which was barely there in the base period. However, hot has become considered normal in the last 30 years. To be more specific, 75 percent of land area on Earth had "hot" summers in the last decade alone, where only 33 percent had "hot" summers from 1951 to 1980 total. 
According to the researchers, an "extremely hot" summer is considered a mean summer temperature that is experienced by less than one percent of Earth's land area during the base period. But since 2006 alone, approximately 10 percent of land area across the Northern Hemisphere had a summer like this. 
"This summer, people are seeing extreme heat and agricultural impacts," said Hansen. "We're asserting that this is casually connected to global warming, and in this paper, we present the scientific evidence for that."
The study noted "extremely hot" summers in other areas besides just the U.S. Midwest, like Texas, Mexico and Oklahoma in 2011 and Eastern Europe, Western Asia and the Middle East in 2010.
This study was published in the journal Proceedings of the National Academy of Sciences

Source: Science Daily

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RE: Cherry picking
By amosbatto on 8/10/2012 4:56:17 PM , Rating: 2
Peer review doesn't mean much in my book. They are gate keepers, if they don't like something(based on personal views), it doesn't get past them. And it does happen. I know, those in the bubble think the peer-review is the holy grail.

Many climate change skeptics seem to think that there is a grand conspiracy to exclude any science which casts doubt on the consensus because it would threatens all their research funding.

The problem with that theory is that a large percentage of funding institutions which would love climate change to not be true and they would gladly fund their research if it were even remotely credible. The Koch brothers are funding anything which looks like it could disprove climate change and Exxon has funded a whole lot of junk science.

Anyone who could truly prove that global warming were a hoax would win wide acclaim and probably win a Nobel Prize for his work. The whole world would be so glad if the science could be disproven, because it would mean that we could avoid all sorts of difficult changes. Look at how hard the politicians are trying to avoid actually doing anything about climate change except talk. Most corporations would love climate change not to true, because they wouldn't have to change their business plans for the next 50 years.

The idea that a couple thousand scientists would conspire to hoodwink the entire world is pretty far-fetched, especially when a lot of their data is in the public domain. What makes it even more unlikely is that their funders (governments and corporations) would love climate change to not be real. The fact that scientists keep coming to conclusions that almost everyone hates should tell you that they are probably telling the truth.

Aside from all that, you can verify a number of things with your own eyes. Look at the number of hurricanes, heat waves and floods that are occurring compared to 50 years ago. Look at all the extreme weather that is occurring which is exactly what Hansen predicted back in 1988. Look at how the coral reefs are bleaching and how animals are migrating. These are things which you can verify yourself.

When uncertain language is used, like possible, potential and the like. I don't trust the findings.

Uncertain language is how science works when you are dealing with natural systems. This isn't the real of pure mathematics, but the messy real world. It is almost impossible to have 100% certainty, but as Bill McKibben noted, the chance that the world would have 327 months in a row with temperatures above the 20th century average is 1 in a google (1 followed by a 100 zeros).

In the end, when I have climate scientists tell me in private they dont' really know for 100% for sure what is going on. Models have about 14 variables they are making assumptions on. There are problems basing our future or policy on, if that is the case.

Yep, and they don't just say it privately. James Hansen notes many limitations of climate models in his book, Storms of My Grandchildren (p. 44, 74, 75-6, 81-2, 226), and he was one of the first to work on climate models. Hansen is the first point out that the models are based upon assumptions and there are many things that the modelers don't know. Hansen says that research priority should be placed in this order:
1. accurate measurement of the current atmosphere,
2. study of the Earth's history,
3. climate models
He trusts climate models the least of the three and thinks they must be constantly verified by current measurements and the Earth's history.

Hansen is up front about the problems with climate modeling:
Thirty years later, models alone still cannot do much better. Here is another killer: Even as our understanding of some feedbacks improves, we don't know what we don't know--there may be other feedbacks. Climate sensitivity will never be defined accurately by models. (p 44)

"People Don't Respect Confidentiality in This Industry" -- Sony Computer Entertainment of America President and CEO Jack Tretton

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