Global Insight into Extreme Events and Land Subsidence: Understanding Drivers, Interplay, and Impacts

Land subsidence (LS) or the relative lowering of the Earth’s ground surface is a critical concern that warrants global attention. LS is a chronic hazard in many areas that has adverse effects on built infrastructure, people, and natural systems. As global atmospheric temperatures rise and the water cycle intensifies, climatic extreme events (e.g., droughts, wildfires, heatwaves, floods) are expected to become more severe. We must therefore better understand the impact of interactions and feedbacks among extreme events, LS, human activities, and their effects around the world. Notably, our global study highlights that LS can alter the potential impacts of extreme events, and extreme events can contribute to LS. We also identify a variety of LS drivers, both natural and anthropogenic (e.g., natural compaction, urbanization, extraction of fossil fuels and groundwater from the subsurface), and corresponding LS rates throughout a variety of climatic zones and environments from the coastline inland. This study presents analysis of anthropogenic-related activities and natural processes that cause LS, but can also enhance climate change as greenhouse gases are released from the soil into the atmosphere (e.g., via permafrost thawing or peatland and wetland removal). Through our synthesis of process-driven relationships and examples, we underscore the interplay of climatic extremes and LS that damages infrastructure and enhances the vulnerability of large populations to floods and other natural hazards. Our study provides guidance for future policies and adaptation and mitigation approaches that account for the critical connections between the land surface, environmental change, and extreme events.