The CRU CY3.21 dataset consists of country averages at a monthly, seasonal and annual frequency, for ten climate variables in 289 countries for the period Jan. 1901 to Dec. 2012. It was produced in 2013 by the Climatic Research Unit (CRU) at the University of East Anglia.
Spatial averages are calculated using area-weighted means. Variables include cloud cover (cld), diurnal temperature range (dtr), frost day frequency (frs), precipitation (pre), daily mean temperature (tmp), monthly average daily maximum (tmx) and minimum (tmn) temperature, vapour pressure (vap), Potential Evapo-transpiration (pet) and wet day frequency (wet).
CRU CY3.21 is derived directly from the CRU TS3.21 dataset. Version numbering is matched between the two datasets.
To understand the CRU-CY3.21 dataset, it is important to understand the construction and limitations of the underlying dataset, CRU TS3.21. It is therefore recommended that all users read the paper referenced below (Harris et al, 2014).
CRU CY data are available for download to all CEDA users.
University of East Anglia Climatic Research Unit; Harris, I.C. (2013): CRU CY3.21: Climatic Research Unit (CRU) Year-by-Year Variation of Selected Climate Variables by CountrY (CY) version 3.21 (Jan. 1901 - Dec. 2012). NCAS British Atmospheric Data Centre, 04 October 2013
. doi:10.5285/f9d4b545-ded2-423c-b61c-f8a67609adf7. http://dx.doi.org/10.5285/f9d4b545-ded2-423c-b61c-f8a67609adf7