A comprehensive new analysis of temperature changes over the continents through 2,000 years has found that a long slide in temperatures in most regions preceded the unusual global warming of recent decades, but with a lot of regional variability and other fascinating details. A National Science Foundation news release has ample background.
The 78-author paper, published Sunday in Nature Geoscience, used a variety of indirect indicators of temperature, from tree rings to pollen grains, to build on other work charting temperature shifts since the end of the last ice age — including the recent Marcott et al paper, explored here, which used seabed sediments to chart 11,000 years of temperatures.
The new paper drew no conclusions about Africa (you’ll see it’s missing from the chart above) because there are too few spots where long climate records accumulate in lakes or caves. (In most other populated regions, instrumental records have covered the last 100 years, but much of Africa remains a data-free zone even now.)
But along with supporting the general picture of a long temperature slide until the modern era’s warming, the analysis reveals fascinating regional variations, including these:
The Arctic was also warmest during the twentieth century, although warmer during 1941–1970 than 1971–2000 according to our reconstruction….
Full Story: http://dotearth.blogs.nytimes.com/2013/04/22/study-charts-2000-years-of-continental-climate-changes/
No comments:
Post a Comment