Climate rather than overgrazing explains most rangeland primary productivity change in Mongolia

Rangelands are Earth’s dominant land type, supporting the livelihoods of more than 2 billion people. Concerns about rangeland degradation typically focus on overgrazing. But climate change may be a greater culprit. Using spatially disaggregated, nationwide data from Mongolia, from 1984 to 2024, we exploited seasonal variation in grazing locations to quasi-experimentally estimate the causal effects of livestock herd size, weather, and climate change on rangeland primary productivity. At interannual frequency, herd size modestly but significantly negatively affects primary productivity, with notable variation across ecological zones. The effects of weather fluctuations are, however, an order of magnitude larger. At the decadal scale, over which herders can adapt to climate change, herd size effects disappear, and temperature effects dominate. In Mongolia, climate change seems to drive most long-term change in rangeland primary productivity.