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J. Overpeck, K. Hughen, D. Hardy, R. Bradley, R. Case, M. Douglas, B. Finney, K. Gajewski, G. Jacoby, A. Jennings, S. Lamoureux, A. Lasca, G. MacDonald, J. Moore, M. Retelle, S. Smith, A. Wolfe, and G. Zielinski.Complete Scientific ReferenceSummary:A large international team of scientists recently combined the results of their research to get the first circum-Arctic view of surface air temperature changes over the last 400 years. Records from 29 sites around the Arctic were averaged to generate the circum-Arctic temperature record shown here. The study used proxy climate data from tree-rings, ice-cores, lake and marine sediments. This "multi-proxy" approach insures that results were not biased as is possible if only one proxy source was used.The exact temperature calibration of the record is less certain than the other studies included in this www site, primarily because many of the individual Arctic records were collected from sites far from any instrumental weather station (nearby climate records allow for a close calibration between proxy records and actual temperature). However, a comparison with the circum-Arctic instrumental temperature record available shows that the paleoclimatic records are good proxies for temperature. Together, they indicate that the Arctic has warmed up to 1.5°C since 1850 - the coolest interval of the Arctic "Little Ice Age." Much of the recent Arctic warming took place between 1850 and 1920, most likely due to natural processes, whereas the warming after 1920 is increasingly difficult to ascribe to natural forcing. The Overpeck et al. results confirm results of earlier regional studies that suggest the Arctic is warming like never before. The authors also discuss the significant impacts of warming across the Arctic. These impacts include glacial melting, permafrost warming, lake and forest ecology changes, and the retreating of sea-ice. |
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Link to more on this study, including data and FTP information... On to the next study... "Pollack et al., 1998." Back to... "Paleo Data of the Last 2000 Years" |
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http://www.ncdc.noaa.gov/paleo/globalwarming/overpeck.html Downloaded Monday, 22-Sep-2008 00:43:09 EDT Last Updated Wednesday, 05-Apr-2006 11:47:30 EDT by paleo@noaa.gov Please see the Paleoclimatology Contact Page or the NCDC Contact Page if you have questions or comments. |