GDHY_v1_2_v1_3

The Global Dataset of Historical Yield (GDHY_v1_2_v1_3) offers annual time series data of 0.5-degree grid-cell yield estimates of major crops worldwide for the period 1981-2016. The crops considered in this dataset are maize, rice, wheat and soybean. The unit of yield data is t/ha. The grd-cell yield data were estimated using the satellite-derived crop-specific vegetation index and FAO-reported country yield statistics. Maize and rice have the data for each of two growing seasons (major/secondary). "Winter" and "spring" are used as the growing season categories for wheat. Only "major" growing season is available for soybean. These growing season categories are based on Sacks et al. (2010, DOI: 10.1111/j.1466-8238.2010.00551.x). The geographic distribution of harvested area changes with time in reality, but we used the time-constant data in 2000 (Monfreda et al., 208, doi:10.1029/2007GB002947). Many missing values are found in the first (1981) and last (2016) years because grid-cell yields are not estimated for these years when growing season spans two calendar years. The data for the period 1981-2010 are the same with the version 1.2 (GDHY_v1_2). For the period 2011-2016, a newly created version 1.3 using the satellite products that are different with earlier versions was alighned to ensure the continuity of yield time series. This version is therefore called "the alighned version v1.2+v1.3".