This document discusses sources of climate and weather data including: 1) Daily weather data from weather stations, gridded datasets, and satellite data which provide information but have limitations and errors. 2) Mean climatology datasets like WorldClim which provide interpolated climate normals but have biases. 3) Future climate data from global climate models (GCMs) which need to be downscaled to higher resolutions to be useful for agriculture due to their coarse scale. Downscaling methods can introduce uncertainties. 4) The document emphasizes selecting the best available data source for the use case, being aware of errors in the data, and using downscaled information carefully when modeling agriculture.