UVANTARCTIC: Reconstruction of historical (subrecent) stratospheric ozone levels in the antarctic: (poly)phenologic compounds in pollen and spores of antarctic plants as indicators of solar UV-B

The ozone hole over the Antarctic in 1985 was discovered in 1985, but meteorological climatological records of stratospheric ozone and solar UV-B from before 1970 are lacking. Enhanced solar UV-B induces polyphenolics in the wall of pollen and spores. These polyphenolics are highly resistant, their chemical structure last for a LONG TIME. The reconstruction of the past UV-B radiation climate, which we propose, is based on the dose response relationship between solar UV-B radiation and polyphenolics in pollen and spores of terrestrial plants. These polyphenolics in pollen en spores are hypothesised to be indicators of the solar UV-B radiation, a new proxy: a tool to reconstruct solar UV-B levels in past times. In addition to pollen and spores collected from (dated) herbarium specimens, pollen and spores in the Antarctic fossil record, such as in frozen moss peat banks at Signy represent an archive of past UV-B. Based on the dose response relationship between the UV-B dose absorbed and the content of polyphenolics determined, the solar UV-B and stratospheric ozone levels of the periods 1920-2000 and 3000 years B.P. upto recent will be reconstructed. Objectives: 1.to obtain dose response relationships between the UV-B dose absorbed by Antarctic plants and the content of polyphenolics in pollen and spores, which may represent a new proxy for reconstruction of solar UV-B levels in past climates. 2. to analyse and quantify polyphenolics in pollen and spores of (dated) Antarctic plant moss specimens from the herbarium collection of the British Antarctic Survey, covering the period 1920-2000. 3. to obtain cores from frozen moss peat banks in the Antarctic (0-3000 yrs Before Present), date plant material, collect and identify pollen and spores and to analyse and quantify polyphenolics in these pollen and spores. 4. to reconstruct historic UV-B levels and stratospheric ozone for the periods 1920-2000 and recent3000 yrs B.P. Uvantarctic is a research project for a postdoctoral fellow by staffmembers of Plant Ecology, Palynology (Palaeoecology) and Analytical Chemistry.