The earth appears to have been warming very slowly for the last 150 years. The temperature rise over that period (less than one degree Celsius) is so slight, however, that projecting it forward for another 100 years gives no cause for alarm
So what is an alarmist going to do in that case? They predict a DEPARTURE from the existing trend due to a "tipping point". But what could cause a "tip"? Their theory is that clouds warm the earth and that an accumulation of clouds as warming proceeds on its gentle way will eventually start a positive feedback cycle, where warming causes more warming.
Now isn't that a simple explanation of Warmism? All the blather boils down to that one paragraph above. But you can see the crucial point: Do clouds really warm the earth? Amazingly enough, Warmists just assume it. They have no proof of the most critical point in their theory. And what evidence on the matter that is available so far suggests the opposite: Clouds COOL the earth. And more evidence has just become available -- and it appears in a very prestigious peer-reviewed journal:
A paper published in the Journal of Geophysical Research finds that a natural atmospheric oscillation, the Southern Annular Mode, is correlated to significant increases in cloud cover resulting in "large scale" local cooling of approximately -2.5C.
The research concerned South America only but South America is a rather large place and any claim that clouds behave differently there from anywhere else is something only a Greenie could even propose, let alone accept.
Understanding sudden changes in cloud amount: The Southern Annular Mode and South American weather fluctuations
By Benjamin A. Laken et al.
This work investigates the cause and effects of extreme changes in synoptic-scale cloud cover operating at daily timescales using a variety of satellite-based and reanalysis data sets. It is found that the largest sudden increases detected in globally averaged cloud cover over the last ten years of satellite-based observations occur following positively correlated shifts in the phase of the Southern Annular Mode (SAM) index. The associated pressure anomalies are found to generate frontal cloud formation over large areas of the South American continent, increasing regional cloud cover by up to 20%; these changes are correlated to statistically significant reductions in local temperatures of approximately −2.5°C with a +1 day time lag, indicating the SAM index is associated with large scale weather fluctuations over South America.
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 117, D13103, 7 PP., 2012