Extremes in temperature, vapor pressure deficit, and soil moisture severely endanger critical functions and services provided by terrestrial ecosystems. Both increasingly extreme long-term trends in environmental conditions and extreme events such as heatwaves, droughts, floods, and unseasonal freezes directly impact key physiological processes such as carbon uptake, transpiration, growth, and mortality. Abundances or scarcities of water, atmospheric dryness, heat, and cold can operate separately or in tandem to reduce terrestrial gross and net primary productivity and elevate risks of plant mortality. However, due to the complexity of these interactions and the lack of continuous time series, it is difficult to quantify the magnitude and timing of stress-related impacts on ecosystem function. As climate change accelerates the occurrence and severity of climatic extremes with consequences for terrestrial ecosystems, we must harmonize our efforts to characterize plant and ecosystem functions and develop frameworks for monitoring and prediction.

In this session, we broadly explore the roles of temperature extremes, evaporative demand, and soil moisture in carbon, water, and energy relations, along with plant mortality across various spatial and temporal scales. We encourage submissions dealing with novel approaches for measuring and modeling plant and soil water status, responses to extreme conditions, and their impacts on ecosystem function. We invite contributions on these topics at scales ranging from individual plant tissues to entire ecosystems, applying experimental, observational, or modeling approaches and dealing with diverse disciplines such as plant physiology, community ecology, ecosystem ecology, land management, and biogeochemistry.