Research on changes in the pace of the water cycle dates back to the 1970s. In the last few decades, leveraging a number of new regional and global datasets, research has highlighted changes in the water cycle and distribution attributed to secular trends in relevant processes and/or to anthropogenic activities, such as irrigation, groundwater pumping, dam and reservoir operations. For example, studies have investigated changes in the rate of exchange across terrestrial water storages and land-atmosphere interactions using different datasets, including remotely sensed, modeled, or data-assimilated, and reanalysis products. Past studies have also differed in their period of analysis, regional focus, and methods for change analysis and attribution. This session aims to provide a platform to present and discuss studies that seek to understand (i) the current state of knowledge on understanding the role of climatic change and the human water management in influencing land-atmosphere interactions and resulting in accelerating or decelerating water cycle processes, (ii) uncertainties and open questions related to this critically important research topic. Studies focused on change analysis of individual or integrated water cycle components and land atmosphere interactions using one or more of the above-mentioned data types and modeling techniques are encouraged, with either a regional or global focus. We are interested in studies that highlight existing uncertainties in the state of knowledge regarding the magnitude or direction of these changes, including changes due to human management. We particularly encourage studies that highlight existing uncertainties in the magnitude or direction of water cycle changes and those that utilize diverse sources of observations and modeling approaches and foster interdisciplinary collaboration to inform sustainable water management strategies.
Sonia Seneviratne