Global Cropland and Pasture Data from 1700-2007

This is a beta release of an updated version of historical cropland data set that spanned the 1700-1992 period. The original data set was described in the publication by Ramankutty and Foley (1999). This release updates the data to the 1700-2007 time period, and additionally includes pastures. This is a complete revision of the data, and not just a simple update of the last 15 years. This is a beta release – investigators have not checked carefully for errors yet, so please use with caution. The data are provided in NetCDF format at 0.5 degree resolution in latitude by longitude, and annual timescale. 5min resolution data as well as data in other formats will become available later. Reference: Ramankutty, N., and J.A. Foley. 1999. Estimating historical changes in global land cover: Croplands from 1700 to 1992, Global Biogeochemical Cycles 13(4): 997-1027.本数据集为覆盖1700-1992年时段的历史耕地数据集更新版本的测试版发布。原始数据集的相关说明已发表于Ramankutty与Foley（1999年）的研究论文中。本次发布将数据集的时间跨度更新至1700-2007年，且新增了牧场数据。本版本为数据集的全面修订，而非仅针对最后15年的简单更新。本版本属于测试发布版——研究人员尚未对数据误差进行细致核查，故使用时请谨慎。数据集以网络通用数据格式（NetCDF）提供，空间分辨率为0.5度经纬度，时间分辨率为年尺度。5分钟分辨率数据及其他格式的数据将在后续发布。参考文献：Ramankutty, N. 与 J.A. Foley. 1999. 《估算全球土地覆盖的历史变化：1700-1992年的耕地面积》，《全球生物地球化学循环（Global Biogeochemical Cycles）》13(4): 997-1027。