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20th Century Not Hottest on Record
By Larry O'Hanlon, Discovery News
April 8, 2003 — A study of more than 240 climate studies covering the last thousand years has found that the 20th century may be just another bump in the climate road.
Over the past several years there has been a surge in research trying to tease out climate history using ice cores, tree rings, lake, river and seafloor sediments, historical records, corals, stalagmites, fossils, dust, pollen, and lots of other ways.
The new study by researchers from the Smithsonian-Harvard Center for Astrophysics, Center for the Study of Carbon Dioxide and Global Change, and the University of Delaware's Center for Climatic Research, brings together all the others.
"There are, indeed some very exciting developments," said Smithsonian astronomer Willie Soon, the lead author of the lengthy study coming out in the next issue of the journal Energy and Environment. "I was thinking that it was the right time to look at the bigger picture."
What the team found was that the 20th century was not the hottest in the last millennium. They also found that nature's climate records back up historical records of a "Little Ice Age" from 1300 to 1900, and a Medieval Warm Period from 800 A.D. to 1300.
The Medieval Warm Period is recorded in high latitudes in tree rings from about 950 to 1100 A.D. Another tree ring database from 14 widespread locations from 30 to 70 degrees north latitude also show the trend. Some...