Input data set: N-Fertilizer (ISIMIP2)

Direct human forcings.

We provide the fertilization rate per our five canonical crop types, i.e. for both annual and perennial C3 and C4 crops, as well as for nitrogen fixing crops. The variables’ names are fertl_c3ann, fertl_c3per, fertl_c4ann, fertl_c4per and fert_c3nfx. The data are provided on an annual times step on the land surface of a global 0.5° × 0.5° grid. The units are kilograms per year and per hectare.

ISIMIP2a/ISIMIP2b: Data is available for the following time periods: historical (1861-2005), rcp26soc+rcp60soc (2006-2099) (see below for detailed information).

We provide fertilization rates for the historical period 1861-2005 and for the years 2006-2099 for the GHG scenarios RCP2.6 and RCP6.0 for all 4 GCMs (GFDL-ESM2M, HadGEM2-ES, IPSL-CM5A-LR and MIROC5). Temporally constant fertilization rates are provided in the 1860soc/, 2005soc/ and 2100rcp26soc/ folders. For instance, the files in 2100rcp26soc/ reuse the fertilization rates of 2100 to build a timeline covering 2100–2299. The other ${some_year}soc data is built in a similar manner.

The data for the historical time period have been provided by the HYDE group (Hyde 3.2), please refer to Goldewijk et al, DOI 10.17026/dans-znk-cfy3 for details. The fertilization rates for future scenarios are based on data provided by the Hurtt group (data set LUH2 v2f). Originally these data were provided on a 0.25° × 0.25° global grid. The ISIMIP team aggregated to the 0.5° × 0.5° grid, and cell fractions below 0.001 are set to 0. Grid cells with undefined values have been filled with a moving window approach and replaced with 0, since various crop models are unable to handle undefined fertilization rates.

For ISIMIP participants, these files are available for download on the DKRZ server.
- ISIMIP2a: /work/bb0820/ISIMIP/ISIMIP2a/InputData/landuse_humaninfluences/n-fertilizer
- ISIMIP2b: /work/bb0820/ISIMIP/ISIMIP2b/InputData/n-fertilizer/