CRU05 DATA - 0.5 DEGREE 1961-1990 MEAN MONTHLY CLIMATOLOGY (Climate Research Unit)
[Status: Not yet available on TerraViva! GeoServer]

CRU05 is a dataset of mean monthly surface climate over global land areas, excluding Antarctica. Interpolated from station data to 0.5 degree lat/lon for a range of variables: precipitation and wet-day frequency, mean temperature and diurnal temperature range (from which maximum temperature and minimum temperature can be determined), vapour pressure, sunshine, cloud cover, ground-frost frequency and windspeed. The data are described in New, M., M. Hulme and P. Jones, 1999: Representing twentieth-century space-time climate variability. Part I: Development of a 1961-90 mean montthly terrestrial climatology. J. Cimate, 12, 829-856.

Preparing this large data set for TerraViva! involved creating more than a thousand individual maps, because for each variable there are monthly observations for each year and each decade. We created map "movies" to make it manageable for the user, so for each variable (precipitation, etc.) there is a map showing the climate at a particular time of year. Here, for example, is a map showing the average mean temperatures in the month of February, which tends to be rather dreary in the Northern Hemisphere. Using Global Data Viewer (GDV) it is possible to "step" through each year of the movie and see the climate change year by year.

These climatic data are particularly powerful when combined with other data, such as the global elevation map. Using Global Data Analyst (GDA), one could determine what areas of the world are suitable for growing, say, coffee, by creating a mask that shows all the places where minimum temperature is never below zero, precipitation is greater than 125 mm per moth but less than 1000, and elevation is higher than 10 m and less than 2500. The CRU05 data are also important because they are widely accepted in the scientific community as a standard calibration tool for multi-year models of climate change. For more information see the IPCC web site which distributes these data in raw form.