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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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Lunacy
By Cascader on 8/8/2012 5:55:36 PM , Rating: 2
Almost all of the carbon based fuels we are burning were initially created during a period of extreme global warming when co2 levels and sea levels were extremely high. This is a proven geologic fact. Common sense would dictate burning and releasing this carbon into the atmosphere will elevate co2 levels and return us to similar conditions.

The particles released when burning coal also block incoming sunlight... up to 20% to be exact. This is a seldom discussed phenomena known as global dimming.
http://youtu.be/p8RyNSzQDaU

To say 7billion human beings and their zeal for consumption will not negatively affect our environment is sheer lunacy. It truly speaks to the ignorance and selfishness of modern society.

Feel free to dismiss these global warming and refuse to take meaningful action. There's a growing suspicion the economy is currently encountering hard limits to growth. Inevitably the naysayers will be forced to give up their consumptive lifestyles whether they want to or not.




RE: Lunacy
By dgingerich on 8/8/2012 6:38:56 PM , Rating: 2
That period was also a period of huge proliferation of life, which is the reason we have the coal and oil. There were huge freshwater swamps throughout the world (which made the coal) and huge areas of high concentrations of algae, with dead zones underneath it (that formed our oil.)

In addition, there is a lot of CO2 that was loose back then that is now locked in coral reefs. So it can't get as high as it was 350 million years ago.

I'd say we'd be better off with such conditions. the ice ages wouldn't be so quick to return, we'd have longer growing seasons and many areas where we could grow a lot of our food year round, and human life would have a better chance to grow and flourish.


RE: Lunacy
By ArcliteHawaii on 8/12/2012 5:49:38 PM , Rating: 2
An increase in global temperature is not to be welcomed. Whenever you increase the energy in a system you increase the disorder and chaos.
* More heat will result in more extreme weather events like tornadoes and hurricanes.
* The rise in the sea levels will reduce the land available for an increasing global population
* Rising sea levels will also inundate fresh water aquifers with salt water, further reducing an already shrinking amount of fresh water on the planet.
* The increase in temperature will cause further drought and desertification of America's breadbasket and that of other countries pushing arable land further north. This land is less productive due to it's acute angle to the sun. Food will be more expensive or even unavailable.
* In addition the heat makes hard to treat tropical diseases more widespread. Already cases of west Nile and malaria are spreading in the US due to the increased average temps.


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