Terrestrial vegetation is a crucial component of the global carbon cycle, as it takes up large amounts of atmospheric carbon dioxide. The future evolution of this carbon uptake is uncertain, with substantial differences across projections of climate models. A major factor contributing to this uncertainty is the largely unknown response of vegetation growth to water availability. This talk will give insights about hydro-climate drivers of satellite-observed vegetation productivity, highlighting strong root-zone soil moisture controls in semi-arid regions.

Overall, the vegetation response to soil moisture changes is globally intensifying during the observational record. Land surface models are shown to have difficulties to accurately capture vegetation-water interactions as well as the observed long-term trends. This also affects their estimation of drought effects on the water cycle.

Our results provide a better understanding of vegetation-water processes which has important implications on ecosystem resilience to drought, and for future model projections of the terrestrial carbon sink.