Impact of Ozone Depletion on Biological Doses

S. DIAZ; C. CAMILION; G. DEFERRARI; H. FUENZALIDA; A. PALADINI; C. BOOTH; S. CABRERA; C. CASICCIA; C. LOVENGREEN; D. NELSON; J. PEDRONI; A. ROSALES; H. ZAGARESE; M. VERNET

Acapulco, Mexico

Simposio; AGU Joint Assembly; 2007

American Geophysical Union

Invited Speaker After the discovery of ozone depletion, the study of the variability of the UV-B radiation at the earth’s surface became a topic of interest for the atmospheric community. Also, biologists, physicians and epidemiologists, working in this field, require values of UV irradiance and dose in their studies. The variation of UV radiation at the earth’s surface is not easily derived from ozone variation, since UV radiation is affected by several other factors, such as solar zenith angle, cloud cover, aerosols, albedo, altitude and earth-sun distance. The response of biological systems to UV radiation is wavelength dependant (action spectrum), then, to perform UV biological studies, the spectral distribution of solar radiation is a key issue. In the last decades, many efforts have been developed to measure UV radiation with spectral or multi-channel instruments. Biologically weighted irradiances are easy to calculate from spectral measurements, but calculation from multi-channel radiometers is not direct. In this study we apply a multi-regressive algorithm to retrieve biologically weighted irradiance from irradiance measured by multi-channel moderate bandwidth radiometers.  Climatologies and extreme events of biologically weighted irradiance are analyzed for ten spectral and multichannel instruments, which are part of the NSF Radiation Monitoring Network and the IAI Radiation Network, and are distributed from South Pole to the tropics. As case study spring year 2000 is shown. Since radiation effects on ecological systems may be accumulative we study the accumulated anomalies to evaluate if they can influence this process.