Agriculture is exposed to weather and climate change in many different ways. Effective, efficient, and appropriate adaptation thus requires understanding in detail where, when, and how crop vulnerability arises. Here I present findings from a series of studies on crop-hydroclimate interactions and their implications for effective policy design. First, using atmospheric and ground-based isotope observations, we show that global distribution of crop water origins and explain why crops that depend more on land-originating moisture are more sensitive to seasonal and sub-seasonal water conditions. Second, we link land-use change within a crop area’s “precipitation-shed” to changes in land-originating atmospheric moisture and rainfall. Focusing on sub-Saharan Africa, we show that the productivity of new croplands tends to be lower than existing croplands, partially due to hydroclimate changes from land conversion / deforestation. Together these findings help illuminate why some croplands are more vulnerable to climate and land use changes than others, what might be done to best adapt in those regions, and how new thinking about terrestrial carbon reserves might help catalyze investment in such adaptations.
