AirSWOT measurements of river water surface elevation and slope: Tanana River, AK. Issue 1 (5th January 2017)

• Record Type: Journal Article
• Authors: Altenau, Elizabeth H.; Pavelsky, Tamlin M.; Moller, Delwyn; Lion, Christine; Pitcher, Lincoln H.; Allen, George H.; Bates, Paul D.; Calmant, Stéphane; Durand, Michael; Smith, Laurence C.
• Is Part Of: Geophysical research letters. Volume 44:Issue 1(2017)
• Page Start: 181
• Page End: 189
• Publication Date: 2017-01-05
• Subjects: AirSWOT -- river hydrology -- remote sensing -- river channels; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2016GL071577
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: Fluctuations in water surface elevation (WSE) along rivers have important implications for water resources, flood hazards, and biogeochemical cycling. However, current in situ and remote sensing methods exhibit key limitations in characterizing spatiotemporal hydraulics of many of the world's river systems. Here we analyze new measurements of river WSE and slope from AirSWOT, an airborne analogue to the Surface Water and Ocean Topography (SWOT) mission aimed at addressing limitations in current remotely sensed observations of surface water. To evaluate its capabilities, we compare AirSWOT WSEs and slopes to in situ measurements along the Tanana River, Alaska. Root‐mean‐square error is 9.0 cm for WSEs averaged over 1 km 2 areas and 1.0 cm/km for slopes along 10 km reaches. Results indicate that AirSWOT can accurately reproduce the spatial variations in slope critical for characterizing reach‐scale hydraulics. AirSWOT's high‐precision measurements are valuable for hydrologic analysis, flood modeling studies, and for validating future SWOT measurements. Key Points: AirSWOT provides a new method for measuring river water surface elevations (WSEs) and slopes without the need for in situ data AirSWOT detects decimeter‐level variations in WSEs for 1 km 2 areas and cm/km‐level variations in river slopes along 10 km reaches Results indicate that AirSWOT is capable of producing measurements useful for validating SWOT‐quality measurements of river WSEs and slopes