Increased Drought Impacts on Vegetation Productivity in Drylands Under Climate Change

Drought plays a critical role in the terrestrial carbon cycle, influencing both ecosystem disturbances and carbon sink dynamics. Here, we assess the effects of future droughts on gross primary production (GPP) under different Shared Socioeconomic Pathways (SSPs). Results show a marked increase in drought frequency, especially extreme droughts by the end of the century. GPP is projected to reduce across most regions, except in high-latitude areas. Extreme droughts cause the largest declines in GPP, particularly in the late century. GPP sensitivity to drought varies by vegetation type and climate zone. Evergreen Broadleaf Forests are particularly vulnerable to all drought intensities, with severe and extreme events showing intensifying impacts over time. Drought impacts are most pronounced in regions with aridity index near 0.15 (dry area) and around 0.8 (humid area). These findings underscore the importance of considering vegetation-specific and climate-sensitive responses to drought when designing future ecosystem mitigation strategies.