Multivariate climate reconstruction for the last 14,000 years in southernmost South America

• Main Authors: Markgraf, Vera, White, James W.C., Figge, Regina A., Kenny, Ray
• Format: Conference Object
• Language: English
• Published: 1995
• Subjects: Atmospheric Sciences; Earth Sciences; Oceanography; Antarctic; Antarc*; Sea ice; Tierra del Fuego
• Online Access: http://aquaticcommons.org/15716/; http://aquaticcommons.org/15716/1/Vera%20Markgraf.pdf

Comparison between past changes in pollen assemblages and stable isotope ratios (deuterium and carbon) analyzed in the same peat core from Tierra del Fuego at latitude 55°S permitted identification of the relative contribution of precipitation versus temperature responsible for the respective change. Major steps in the sequence of paleoenvironmental changes, such as at 12700, 9000, 5000, and 4000 years ago are apparently related only to increase in precipitation, reflecting the latitudinal location and intensity of the westerly storm tracks. On the other hand, high paleoenvironmental variability, which is characteristic for the late-glacial and the latest Holocene, is related to temperature variability, which affects the relative moisture content. Comparison with other paleoenvironmental records suggests that the late-glacial temperature variability is probably related to variability in the extent of Antarctic sea-ice, which in turn appears to be related to the intensity of Atlantic deep-water circulation. Temperature variability during the latest Holocene, on the other hand, is probably related to the dynamics of the El Niño/Southern Oscillation.