Mark New (1,*), David Lister (2), Mike Hulme (3), Ian Makin (4) A high-resolution data set of surface climate over global land areas Climate Research, 2000, Vol 21, pg 1-25 (1) School of Geography and the Environment, University of Oxford, Mansfield Road, Oxford OX1 3TB, United Kingdom (2) Climatic Research Unit, and (3) Tyndall Centre for Climate Change Research, both at School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom (4) International Water Management Institute, PO Box 2075, Colombo, Sri Lanka ABSTRACT: We describe the construction of a 10-minute latitude/longitude data set of mean monthly surface climate over global land areas, excluding Antarctica. The climatology includes 8 climate elements - precipitation, wet-day frequency, temperature, diurnal temperature range, relative humidity,sunshine duration, ground frost frequency and windspeed - and was interpolated from a data set of station means for the period centred on 1961 to 1990. Precipitation was first defined in terms of the parameters of the Gamma distribution, enabling the calculation of monthly precipitation at any given return period. The data are compared to an earlier data set at 0.5º latitude/longitude resolution and show added value over most regions. The data will have many applications in applied climatology, biogeochemical modelling, hydrology and agricultural meteorology and are available through the School of Geography Oxford (http://www.geog.ox.ac.uk), the International Water Management Institute "World Water and Climate Atlas" (http://www.iwmi.org) and the Climatic Research Unit (http://www.cru.uea.ac.uk). ---------------------------------------------------------------------------- This readme file is a brief description of the formats and units in the CRU/Oxford/IWMI 10-minute mean climate grids for global land areas. Please read the pdf document of the above article on this site (new_et_al_10minute_climate_CR.pdf), for details of the data sources, gridding methodology, etc. BEFORE contacting the distributers with queries. The file grid_10min_problems.txt lists all known problems with the data. Nomenclature and Units ---------------------- pre precipitation mm/month cv of precipitation percent rd0 wet-days no days with >0.1mm rain per month tmp mean temperature Deg C dtr mean diurnal temp- Deg C (note tmx=tmp+0.5*dtr; tmn=tmp-0.5*dtr) erature range reh relative humidity percent sunp sunshine percent of maximum possible (percent of daylength) frs ground-frost no days with groudn-frost per month wnd 10m windspeed m/s elv elevation km Data format ----------- 1. All grid files except elevation (elv) and precipitation (pre) latitutde, longitude, 12 monthly values (Jan to December) lat and lon are in degrees decimal format='(2f9.3,12f7.1)' Example (first line of tmp file): -59.083 -26.583 0.2 0.3 0.2 -1.9 -6.0 -9.8 -13.6 -9.2 -8.1 -5.3 -2.3 -1.1 2. Precipitation latitude, longitude, 12 monthly means of precip, 12 monthly CVs of precip format='(2f9.3,24f7.1)' Example (first line of pre file): -59.083 -26.583 105.4 121.3 141.3 146.7 159.6 162.4 141.5 151.1 141.6 124.9 110.0 93.9 35.2 38.7 38.4 27.5 49.5 40.8 50.8 33.5 42.2 56.6 35.5 43.4 3. Elevation latitude, longitude, elevation format='(3f9.3)' Example (first line of elv file): -59.083 -26.583 0.193