I had an interesting climate change discussion over turkey dinner yesterday my cousin claimed that the climate change skeptics have to prove that man-made global warming was false. I on the other hand argued the proponents of the great hoax have to prove that global warming was really happening, that it was caused by man and that it would really have the apocalyptic results its proponents claim.
This new study, which was funded by the National Science Foundation and published by the journal Science, suggests that the of global warming created by doubling of the CO2 in the atmosphere will not produce the cataclysmic results predicted some previous studies including the infamous UN IPCC.
This study was produced by people who believe in global warming but based on their work they believe the most dramatic projections of temperature increases from the doubling of CO2 are not very likely to happen
“Many previous climate sensitivity studies have looked at the past only from 1850 through today, and not fully integrated paleoclimate date, especially on a global scale,” said Andreas Schmittner, an Oregon State University researcher and lead author on the Science article. “When you reconstruct sea and land surface temperatures from the peak of the last Ice Age 21,000 years ago – which is referred to as the Last Glacial Maximum – and compare it with climate model simulations of that period, you get a much different picture.
“If these paleoclimatic constraints apply to the future, as predicted by our model, the results imply less probability of extreme climatic change than previously thought,” Schmittner added.
Some previous studies have claimed the impacts could be much more severe – as much as 10 degrees or higher with a doubling of CO2 – although these projections come with an acknowledged low probability. Studies based on data going back only to 1850 are affected by large uncertainties in the effects of dust and other small particles in the air that reflect sunlight and can influence clouds, known as “aerosol forcing,” or by the absorption of heat by the oceans, the researchers say.
To lower the degree of uncertainty, Schmittner and his colleagues used a climate model with more data and found that there are constraints that preclude very high levels of climate sensitivity.
The researchers compiled land and ocean surface temperature reconstructions from the Last Glacial Maximum and created a global map of those temperatures. During this time, atmospheric CO2 was about a third less than before the Industrial Revolution, and levels of methane and nitrous oxide were much lower. Because much of the northern latitudes were covered in ice and snow, sea levels were lower, the climate was drier (less precipitation), and there was more dust in the air.
The dust in the air reflects some of the heat back toward the sun and according to the study it mitigates some of the the CO2 results, in fact their analysis predicts the most probable result when double CO2 occurs is actually a rise of just 2.3°C which is only slightly above the 2°C limit the hoaxers say we need to stay within.
Schmittner said continued unabated fossil fuel use could lead to similar warming of the sea surface as reconstruction shows happened between the Last Glacial Maximum and today.
“Hence, drastic changes over land can be expected,” he said. “However, our study implies that we still have time to prevent that from happening, if we make a concerted effort to change course soon.”
There is even time for real research to determine the effect of the so called greenhouse gasses on the atmosphere, because until now everything released by the global warming proponents have been tainted by their obvious attempts to cover-up the truth.