Abstract
Abstract. The total water storage change (TWSC) over land is a major component of the global water cycle, with a large influence on the climate variability, sea level budget and water resource availability for human life. Its first estimates at a large scale were made available with GRACE (Gravity Recovery and Climate Experiment) observations for the 2002–2016 period, followed since 2018 by the launch of the GRACE-FO (Follow-On) mission. In this paper, using an approach based on the water mass conservation rule, we propose to merge satellite-based observations of precipitation and evapotranspiration with in situ river discharge measurements to estimate TWSC over longer time periods (typically from 1980 to 2016), compatible with climate studies. We performed this task over five major Asian basins, subject to both large climate variability and strong anthropogenic pressure for water resources and for which long-term records of in situ discharge measurements are available. Our Satellite Water Cycle (SAWC) reconstruction provides TWSC estimates very coherent in terms of seasonal and interannual variations with independent sources of information such as (1) TWSC GRACE-derived observations (over the 2002–2015 period), (2) ISBA-CTRIP (Interactions between Soil, Biosphere and Atmosphere CNRM – Centre National de Recherches Météorologiques – Total Runoff Integrating Pathways) model simulations (1980–2015) and (3) the multi-satellite inundation extent (1993–2007). This analysis shows the advantages of the use of multiple satellite-derived datasets along with in situ data to perform a hydrologically coherent reconstruction of a missing water component estimate. It provides a new critical source of information for the long-term monitoring of TWSC and to better understand its critical role in the global and terrestrial water cycle.
Highlights
Continental freshwater, excluding ice caps, represents only a few percent of the total amount of water on Earth
The total water storage change (TWSC), comprising of all water mass variations from surface waters, soil moisture, snowpack, glaciers and groundwater, is of high interest because it represents a good indicator of potential long-term water cycle (WC) modifications related to natural or anthropogenic factors (Rodell et al, 2018)
The specific seasonality of each basin is well characterized by the Satellite Water Cycle (SAWC) reconstruction; see for instance the difference between the Mekong and the Brahmaputra seasons
Summary
Continental freshwater, excluding ice caps, represents only a few percent of the total amount of water on Earth. It has a major impact on the terrestrial environment and human life and activities and plays a very important role in climate variability. Understanding and predicting continental water storage variations is a topic of great importance for climate research, global water cycle studies (IPCC, 2014) and water resource management. Monitoring long-term spatiotemporal changes in continental freshwater storage has become fundamental. This question is important for regions such as southern Asia that experienced drastic changes over the last decades.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
