**You are going to predict the yield of wheat and maize under climate change conditions.** Projected mean growing-season radiation and temperature are increasing each decade, and precipitation patterns are changing. The CO2 level is also rising, which can have a fertilisation effect on yields - but the effect of this depends on the crop’s photosynthesis pathway, which is different for maize and wheat.
In reality, irrigation and fertilisation would also vary over time, adding complication. However, in these simulations, this doesn’t need to be considered. We work only with water-limited yields, which means all grid cells are rainfed, and crops are fertilised at the same rate for all years, varying by country.
We have restricted the grid cells to areas which are heavily harvested (at least 2000 hectares), and we are providing 30 days of climate data before sowing at each grid cell and 210 days after to use as predictive features. The growing season will not necessarily last exactly 210 days. Crops are harvested when they reach maturity, but the maturity process is influenced by the effects of the weather, fertilization, CO2 level and soil type.
We included below a few visualisations of the behaviour of the climate variables, so that these variabilities and distribution shifts become more clear.
We include some maps of the management forcing data (nitrogen fertilization rate and soil texture). These vary spatially, based on recent observation datasets, and are held constant over time for these simulations.
Finally, we are only using for training and testing pixels where >2000 hectares are harvested (as of the year 2000). To illustrate this, we provide an example map of these pixels, coloured according to the yields in the second year of the training set for each crop.
