Abstract
Abstract. Two daily gravity field solutions based on observations from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are evaluated against daily river runoff data for major flood events in the Ganges–Brahmaputra Delta (GBD) in 2004 and 2007. The trends over periods of a few days of the daily GRACE data reflect temporal variations in daily river runoff during major flood events. This is especially true for the larger flood in 2007, which featured two distinct periods of critical flood level exceedance in the Brahmaputra River. This first hydrological evaluation of daily GRACE gravity field solutions based on a Kalman filter approach confirms their potential for gravity-based large-scale flood monitoring. This particularly applies to short-lived, high-volume floods, as they occur in the GBD with a 4–5-year return period. The release of daily GRACE gravity field solutions in near-real time may enable flood monitoring for large events.
Highlights
Floods are dynamic events, which may only take hours to days to develop and drain
Two daily gravity field solutions based on observations from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are evaluated against daily river runoff data for major flood events in the Ganges– Brahmaputra Delta (GBD) in 2004 and 2007
This study presents a hydrological evaluation of daily GRACE gravity field solutions based on a Kalman filter approach, which are scheduled for an operational run in 2017 with a time delay of just 5 days, in part enabled by quick-look Level-1 data with a time delay of 1 day (made available on request by NASA Jet Propulsion Laboratory (JPL)), by comparing the time series to observed river runoff in the Ganges–Brahmaputra Delta (GBD) under flood conditions
Summary
Floods are dynamic events, which may only take hours to days to develop and drain. For monitoring purposes, Earth observation products need to be available sufficiently frequently to capture the progressing stages of a flood event. Is at best 7–10 days, but most reliably 1 month, caused by a need to accumulate GRACE observations over this time period Both latency and temporal averaging currently limit the potential use of the GRACE Level-3 products (i.e., TWSAs) for flood monitoring and early-warning systems. This study presents a hydrological evaluation of daily GRACE gravity field solutions based on a Kalman filter approach, which are scheduled for an operational run in 2017 with a time delay of just 5 days, in part enabled by quick-look Level-1 data with a time delay of 1 day (made available on request by NASA Jet Propulsion Laboratory (JPL)), by comparing the time series to observed river runoff in the Ganges–Brahmaputra Delta (GBD) under flood conditions. In July and September 2007, two separate major flood peaks in the Brahmaputra caused inundation lasting weeks, affecting 42 % of the country (Islam et al, 2010)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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.
