DeSurvey Module 1.1 Climate Data (Vasto, April 4-7, 2006) Tom Holt Climatic Research Unit University of East Anglia Norwich, UK

Objectives for Year 1 (pt 1) extract regional subsets of data from global 6-hourly ERA-40 data on n80 grid to any region 1 x 1 deg lat/long grid extract regional subsets of data from global 6-hourly ERA-40 data on n80 grid to any region 1 x 1 deg lat/long grid downscale from ERA-40 data on 1x1 deg grid to a 1 km grid downscale from ERA-40 data on 1x1 deg grid to a 1 km grid –Thin plate spline interpolation with topography as added spatial covariate produce 1 km data for n degrees about any central node over the Mediterranean produce 1 km data for n degrees about any central node over the Mediterranean

Objectives for Year 1 (pt 2) Validate downscaled data against station observations at different altitudes Validate downscaled data against station observations at different altitudes –Stations from Greece and Portugal –Calibrate downscaling against station data if needed Document the methodology Document the methodology Extend method to more coarse resolutions, e.g. 20 km grid Extend method to more coarse resolutions, e.g. 20 km grid –These can be complete gridded data sets

Objectives for Year 1 (pt 3) repeat the downscaling using Regional Climate Model data from the PRUDENCE archive repeat the downscaling using Regional Climate Model data from the PRUDENCE archive –Gives data for and document climate analysis methods document climate analysis methods These objectives are essentially D due month 12. These objectives are essentially D due month 12. Setup ftp site for data and software Setup ftp site for data and software

Status (part 1) We are about 6 weeks late with D because the ERA-40 data were literally being processed by BADC as we wanted them (there were errors!) We are about 6 weeks late with D because the ERA-40 data were literally being processed by BADC as we wanted them (there were errors!) All ERA-40 data are now available All ERA-40 data are now available Downscaling method is complete Downscaling method is complete Validation is almost complete Validation is almost complete software written to process model data software written to process model data

Status (part 2) documentation on methodology is about 80% complete documentation on methodology is about 80% complete Once validation is complete, downscaling can be completed in a matter of days Once validation is complete, downscaling can be completed in a matter of days Evora has completed work on climate background to drought in Portugal Evora has completed work on climate background to drought in Portugal –Paper submitted IJC

Status (part 3) NOA Athens is in the process of validating downscaling NOA Athens is in the process of validating downscaling –Poster accepted for EGU UEA has developed a PCA-based set of global predictors based on ERA-40 mslp UEA has developed a PCA-based set of global predictors based on ERA-40 mslp –Uses EM algorithm method to overcome problems with speed and instability –To be used for any ambient climate studies

Status (part 4) Conversion of downscaling software to R is underway Conversion of downscaling software to R is underway –For DeSurvey Surveillance System Software for analysis of climate extremes is written Software for analysis of climate extremes is written –Easily converted from Matlab to R Summary: ahead on some things, behind on others! Summary: ahead on some things, behind on others!

Does downscaling work? (pt 1)

Top row: Scatter plots of the observed vs. estimated temperature data. Bottom row: Daily differences of the two datasets over the period.