Jung, H. ., The Ohio State University, Columbus, USA, jung.196@osu.edu
Alsdorf, D. ., The Ohio State University, Columbus, USA, alsdorf.1@osu.edu

REPEAT-PASS INTERFEROMETRIC SAR MEASUREMENTS OF SEASONAL CHANGES IN CONGO FLOOD WATER ELEVATIONS

The Congo River has the second-largest flow in the world, behind the Amazon, and the second-largest watershed of any river, again trailing the Amazon. The impact and connections of this hydrologic flux with the region’s climate, biogeochemical cycling, and terrestrial water storages, especially in floodplains, is of great importance. However, there is a lack of published research documenting the Congo Basin terrestrial water storage on the floodplains. Interferometric processing of JERS-1 SAR data from four locations in the central Congo Basin provides centimeter-scale measurements of water level change (dh/dt). As in the Amazon Basin, inundated vegetation is needed to return the radar pulse to the antenna from the specular water surface. Computed differential interferometric SAR phase values and their unwrapped values show water level fluctuations and reveal the main factors, such as channels and topographic bowls (i.e. slightly lower areas), that affect the hydraulics of flow on the floodplains. Our research shows that Amazon floodplain channels play an important role in that basin’s water flow, which appears to be a localized process, whereas the Congo does not show similar floodplain channels and the related dh/dt phase values are broadly distributed. Spatially integrated observations of dh/dt are being used to estimate changes in floodplain storage, a vital parameter in basin-wide hydrologic models.

Poster presentation

Presentation is given by student: Yes
Session #:006
Date: 03-03-2008
Time: 17:30 - 19:30