EcoChange : climate data
CRU CL 2.0 data
- The CRU CL 2.0 surface climate fields were produced by interpolation of meteorological station data means for the period from 1961 to 1990.
- "Days with ground-frost" are defined as the frequency of grass minimum temperatures < 0°C.
- "Rain day" frequencies express the number of days per month with precipitation > 0.1 mm.
- The spatial availability of data for each PRUDENCE model differs,
i.e. the SMHI-RCAO, CNRM-Arpège and HC-HadRM3P models cover different areas.
None of them covers the southern and eastern sides of the common geographical window.
- Data for some model experiments are not available:
"Wind speed" data for CNRM-Arpège (A2 scenario),
"Snow amount" data for HC-HadRM3P (all scenarios).
- The period covered by each ENSEMBLES model simulation varies:
KNMI-RACMO2 spans from Jan. 1950 to Dec 2100,
DMI-HIRHAM5 spans from Jan. 1951 to Dec. 2100, and
HC-HadRM3Q0 spans from Jan. 1951 to Nov. 2099.
However, the time dimension of each long-term data file (ordered 1st in each table cell, pages 6-8) is the same (i.e. 1812 months = 12 calendar months × 151 years);
missing monthly data are infilled with the default value (i.e. -999).
- Values for mean climates for 1961-1990 and 2071-2100 (ordered 2nd and 3rd in each table cell) were estimated by averaging the long-term monthly data.
For the HC-HadRM3Q0 model experiments the 2071-2100 mean climates were estimated using the available data (i.e. from Jan 2071 to Nov. 2099).
- HC-HadRM3Q0 data are not available for some fields:
"Daily minimum temperature", "Daily maximum temperature" & "Fractional snow cover".
- DMI-HIRHAM5 data for Nov. & Dec. 2050, should be treated with caution, since an inconsistency has been found in the respective climatic fields.
Another inconsistency is presented by "Fractional snow cover", which appears to be quite limited across Europe.
The model simulation will be reprocessed by DMI to correct these problems.
PET data (all sources)
- Potential (Reference) Evapotransipration data were derived on the basis of the FAO-56 Penman-Monteith method [Allen et al., 1998] using either observed or modelled climate data.
- PET data that appear to extend over sea and lakes, for several model experiments, should be discounted when one downscales to higher spatial resolutions in regions close to coastlines.
Vapour pressure data (all sources)
- Vapour pressure data were derived by employing humidity-calculation formulas and the relevant surface climate data available in each case:
"relative humidity and min/max temperature", "specific humidity & surface atmospheric pressure", or "dew-point temperature & mean temperature".