1. EDUCE: WP1 Climatological UV Maps A. Bais, K. Tourpali, A. Kazantzidis Aristotle University of Thessaloniki Laboratory of Atmospheric Physics

2. Objectives Develop a methodology for constructing maps of surface UV over Europe Apply this methodology to a sample of UV data from EUVDB Deliver climatological maps of surface UV in various time scales Focus on daily UV doses (CIE weighted)

3. Problems Density - distribution of UV sites in Europe –Small number of stations –Uneven distribution of stations

5. Problems Density - distribution of UV sites in Europe –Small number of stations –Uneven distribution of stations Derivation of daily doses from spectral data –Frequency of available spectra –Spectral range of single Brewers (290-325 nm)

8. Problems Density - distribution of UV sites in Europe –Small number of stations –Uneven distribution of stations Derivation of daily doses from spectral data –Frequency of available spectra –Spectral range of single brewers (290-325 nm) Spatial interpolation of data

9. Methodology 1 Definition of the area around each UV station represented by the station’s UV variability –Daily maps (1.5°x1.25°) of daily UV dose for 1979-92 (courtesy S. Madronich, C. Fischer, NCAR) Tropospheric ultraviolet and visible model (TUV) TOMS total ozone TOMS reflectivity to account for clouds Altitude of each grid-point –Monthly correlation fields for the grids corresponding to each EUVDB station

10. Methodology 2 Maps of daily UV doses –Construct a UV map using a RT model Based on total ozone, reflectivity (or clouds) –Extract measured doses (EUVDB) at all sites –Modify the model-based UV field using the measured doses within an area defined by the correlation field around each station –Discard all other grids (lower correlations)

11. Correlation field around the UV stations of EUVDB JULY-AUGUST

12. Work Plan Use TOMS UV to derive the correlation fields and compare the two methods Derive correlations of UV variability between grid-points at EUVDB stations Derive correlations of UV variability between stations using measured doses Construct climatological UV maps using data from EUVDB and post the maps on the web