From project webpage:
VASClimO was a joint climate research project of the Global Precipitation Climatology Centre (GPCC) at the German Met Service (DWD) and the Institute for Atmosphere and Environment – Working Group for Climatology at the Johann Wolfgang Goethe University Frankfurt.
The project was funded by the Bundesministerium für Bildung, Wissenschaft, Forschung und Technologie BMBF within the German Climate Research Program DEKLIM(DEKLIM Project-No.: 33 11 0307 - "Development of an observational data basis (Europe and global) for DEKLIM and related statistical analysis with regard to climate variability on a decadal to centennial time scale"). Funding was provided over a 5-year period for 3 scientists. Two scientists (Dr. Christoph Beck and myself) spent their time in part project A at GPCC. Their task was the creation of worldwide gridded datasets of 4 meteorological variables (precipitation, near surface temperature, snow cover and air pressure) in 2 temporal resolutions (monthly and daily). The datasets should have been built on long, quality controlled (homogeneity, outliers, station location) records of observations.
[...] The final dataset consists of gridded monthly precipitation data for the global land areas (excluding Greenland and Antarctica) from 1951 to 2000. It is gridded at three different resolutions (0.5° lat/lon, 1.0° lat/lon, 2.5° lat/lon) on the basis of long and nearly gap-free quality controlled station records. The dataset is now available for use in scientific research and can be downloaded as version 1.1 dated August 2005.
See this readme for detailed information on formats.
No explicit information on reuse, but does ask for attribution:
Please cite the dataset as: Beck, C., J. Grieser and B. Rudolf (2005): A New Monthly Precipitation Climatology for the Global Land Areas for the Period 1951 to 2000. Published in Climate Status Report 2004, pp. 181 - 190, German Weather Service, Offenbach, Germany.
Variability Analysis of Surface Climate Observations (VASClimO). No author.
Retrieved 10:56, May 24, 2013 (UTC).
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