Weather and Climate
HarvestChoice uses several weather and climate data sources in a number of ways:
- Long term monthly climate data are used in the characterization and mapping of agroecological zones.
- Monthly long-term average and time series data are used in assessing the potential prevalence of specific pests and diseases.
- Daily weather and monthly climate data time series are used in the modeling of crop growth.
We also use two sources of modeled climate data for specialized applications:
- Potential changes in the climate patterns and variability as a consequence of climate change (WorldClim
). - Stochastic point estimates of daily climate variables in the sub-tropics and tropics
(MARKSIM). - Spatially-downscaled climate projection for 2030/2050/2080
(FutureClim).
While HarvestChoice is a secondary user of weather and climate data, we are working with partners to downscale existing data sources to generate weather/climate variable estimates at a higher resolution, e.g.,
- Temporal downscaling of CRU 30 arc minutes (0.5 degree) time-series climate data from monthly to daily resolution, and
- Spatial downscaling of NASA POWER daily weather data from 60 arc minutes (1 degree) to 5 arc minutes (10 km) resolution, using elevation as a covariable.
Currently the main source of daily historical weather data used in HarvestChoice researches is NASA Prediction of World Energy Resources (POWER): Agroclimate Database. The POWER provides satellite remote sensing-estimated daily weather variables (e.g., minimum and maximum temperature, rainfall, and solar radiation) globally at 1-degree grids, including:
- Solar radiation (daily total): From July 1983 through June 2005; and July, 2006 through current with one month delay
- Air temperature (daily average, minimum, maximum): From January 1983 through December 2006
- Dew point temperature (daily average): From January 1983 through December 2006
- Rainfall (daily average): From January 1997 - current with two month delay
Due to the nature of remote sensing-based estimation methods, the quality of data is sometimes questioned in mountainous areas or areas nearby big towns (e.g., heat islands), but localized verifications with station-based point data at agricultural lands in relatively flat terrain showed reasonable correlations.
Long-term climate data is used in cropping systems characterization as well as assessing risks associated with climate variability. The main source of climate data used in HarvestChoice researches is the University of East Anglia Climate Research Unit Time-Series (CRU-TS) Global Climate Data 3.0: Reformatted for Spatial Analysis by CGIAR-CSI. The CRU-TS dataset has monthly time-series of climate variables, for the period 1901-2006, covering the global land surface at 0.5 degrees resolution. The climate variables available through this dataset are:
- Mean, minimum and maximum temperature
- Diurnal temperature range
- Precipitation
- Wet day frequency
- Frost day frequency
- Vapor pressure
- Cloud cover
Data Download Link
