Environment & Energy
Related: About this forumNature - 20 Years Of Hot Arctic Summers Not Statistical Noise; Hottest In 600 Years
The Arctic has seen warmer summers over the past two decades than at any time in the past 600 years, according to a study published this week in the journal Nature. The study uses a sophisticated statistical approach, known as Bayesian modeling, to show that the extremely warm summers in high northern latitudes are evidence of an overall warming trend, rather than just a temporary fluctuation in an otherwise unchanging climate.
Thats a crucial distinction: a natural fluctuation might reverse before the full effects of warm temperatures could set in, including the melting of Greenlands ice cap, which could lead to a significant rise in sea level, and ice-free summers in the Arctic Ocean, which could trigger problematic weather anomalies in other parts of the globe.
Scientists have already shown that a warming climate will automatically generate more high-temperature records than a stable one. Thats because individual temperature measurements in a given location form a bell curve, with the greatest number of readings falling into the normal range for that location. A small number of readings will fall well above normal, however, and an equally small number will fall below.
If the normal range shifts, however, because the climate is warming overall, high temperatures that once came along very rarely will happen more often, while extreme cold temperatures will become even rarer. A 2012 paper by James Hansen, who recently retired from his post at NASAs Goddard Institute for Space Studies, showed how this must be true for daily temperatures, but the same principle applies to seasonal averages.
EDIT
http://www.climatecentral.org/news/study-arctic-summers-warmest-in-600-years-15873
pscot
(21,023 posts)They will kick your ass.
jpak
(41,742 posts)so we can laugh Teh Junk Science away...
yup