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Global 30-Year Mean Monthly Climatology, 1930-1960, V. 2.1 (Cramer and Leemans)


This database is a major update of the Leemans & Cramer database (Leemans & Cramer 1991). It currently contains monthly averages of mean temperature, temperature range, precipitation, rain days and sunshine hours for the terrestrial surface of the globe, gridded at 0.5 degree longitude/latitude resolution. It was generated from a large data base, using the partial thin-plate splining algorithm developed by Michael F. Hutchinson, Canberra (Hutchinson & Bischof 1983).

Before using this data set in a publication, please contact the data originator with a brief explanation of the intended use.

Wolfgang Cramer
Potsdam Institute of Climate Impact Research
Tel.: +49-331-288-2521     Fax : +49-331-288-2600

Data Citation

Cite this data set as follows (revised on June 28, 2002):

Cramer, W. P., and R. Leemans. 2001. Global 30-Year Mean Monthly Climatology, 1930-1960, V2.1 (Cramer and Leemans). ORNL DAAC, Oak Ridge, Tennessee, USA. doi:10.3334/ORNLDAAC/416.


Hutchinson, M. F., and R. J. Bischof. 1983. A new method for estimating the spatial distribution of mean seasonal and annual rainfall applied to the Hunter Valley, New South Wales. Australian Meteorological Magazine 31:179-184.

Leemans, R., and W. P. Cramer. 1991. The IIASA database for mean monthly values of temperature, precipitation and cloudiness of a global terrestrial grid. Report no. RR-91-018. International Institute for Applied Systems Analysis (IIASA). Laxenburg, Austria.

Data Format:

The data set currently consists of five files:

clou.grd (2f6.1,12f3.0) : lon, lat, monthly sunshine hours in & of possible

prec.grd (2f6.1,12f5.0) : lon, lat, monthly mean precipitation

rd.grd (2f6.1,12f3.0) : lon, lat, monthly mean number of rain days

tmean.grd (14f6.1) : lon, lat, monthly mean temperature

tran.grd (14f6.1) : lon, lat, monthly mean temperature range

All grd-files contain the same 62483 pixels in the same order, with 30' latitude and longitude resolution. The coordinates are in degree-decimals and indicate the SW corner of each pixel. Topography is from ETOPO5 and indicates modal elevation. Other resolutions may be added later.

The data files are compressed using the gzip command under unix. Uncompress them with gunzip under unix, or with winzip or something similar on a non-unix machine.

Document Information:

Document Revision Date:

August 29, 2001 (Note: Citation revised on June 27, 2002)

Document Review Date:

August 29, 2001

Document Curator:

Document URL: