Remote Sensing of River Widths and Discharge Estimation for the Mainstem Congo River

To conduct research in a study area such as the Congo basin is extremely difficult. The central African region is large and demanding to traverse. Obtaining the data necessary for calculating discharge in the field requires large amounts of time and funding; thus available data are very sparse. A much more efficient way to estimate discharge would be to estimate the variables from space-borne remote sensing measurements. The forthcoming NASA Surface Water and Ocean Topography satellite mission will measure river height, slope, and width. Not all variables necessary for determining discharge can be measured from remote sensing. The focus of this thesis is on measurement of river width via Landsat imagery and an automated width calculation algorithm. Depth was calculated using an approximation for reach-averaged depth from drainage area, adjusted for within-reach variations in river width. By combining these two variables with a constant Manning’s n and surface slope measurements, Manning’s open channel flow equation for discharge can be used. The measured mainstem Congo width ranged from 242 meters to 15,773 meters. The average estimated discharge of the mainstem was calculated to be 68,209 m3/sec, which was greater than what was recorded at the Kinshasa station by 25,136 m3/sec. It is hypothesized that the over estimation of discharge is due to the estimation of depth. Future improvements of RivWidth would improve automatic mainstem width measurement efficiency.No embarg