Research data: Evaluating the effects of climate change and CO2 fertilization on the irrigation demand assessment in South-West France

Data and code for the SIMETAW simulations of CO2 fertilization effects on crop water use and irrigation needs in the Aude department (France) This repository contains the code and input data needed to run the SIMETAW-based simulations of reference evapotranspiration (ET0), crop evapotranspiration (ETc, ETa) and net irrigation requirements (NAc) for the Aude department, under historical and future climate scenarios (RCP2.6, RCP4.5, RCP8.5), with and without the CO2 effect. Contents SIMETAW__LGP_only_corrected_ws.r: R script for the simulation with CO2-dependent surface resistance (CO2 fertilization effect). Needs the CO2_table_*.csv files. SIMETAW__LGP_only_NOCO2_ws.r: same simulation with fixed surface resistance (no CO2 effect). Used as the reference case. Soil_and_land_data_Aude/ (static inputs, all on the same grid as the climate data): mask_Aude.nc: land mask; cells outside the mask are skipped. EM_Aude.nc: elevation, used to compute atmospheric pressure. awc_Aude.nc: soil available water capacity (AWC) [units: to be checked]. In the scripts the AWC values are set by AWC_aude. Sdepth_Aude.nc: soil depth, used to limit the effective root depth. crop_table.csv: crop look-up table: growth-stage lengths, crop coefficients (Kc), planting and harvest dates, maximum root depth and irrigation methods for each crop code. CO2_table_historical.csv, CO2_table_rcp26.csv, CO2_table_rcp45.csv, CO2_table_rcp85.csv: annual atmospheric CO2 concentration [ppm] for each scenario. Surface_Agricoles.xlsx: agricultural area by crop in the Aude department [to be checked: source and use, e.g. weighting the results by crop area]. [Climate data: to be checked whether it is included in this repository or deposited separately.] Daily bias-corrected climate data for 5 regional climate models (CNRM-CNRM, CNRM_KNMI, MPI-SMHI, NCC-GERIC, NCC-SMHI), for the historical period (1976-2005) and the scenarios (2006-2100). Variables: tasmin, tasmax, pr, hurs, rsds, rlds, sfcWind. Files are named aude_<variable>_<model>_<scenario>_<period>_daily.nc. How to run Put the input files in the folders expected by the scripts, or edit in_dir, cl_dir and wd at the top of each script (the paths in the scripts are machine-specific). Run SIMETAW__LGP_only_corrected_ws.r and SIMETAW__LGP_only_NOCO2_ws.r in R. Required packages: sp, ncdf4, chron, raster, lubridate, stringr, hyfo. Outputs are yearly NetCDF files, for each model, scenario, crop and AWC value: ET0, and ETc, ETa and NAc over the growing season.