Time series for water levels in virtual gauge stations in the Amazon basin using satellite radar altimetry

Abstract

Using satellite altimeter radar technology for monitoring changes in water levels at continental scale is a relatively recent ad- vance. Several studies have demonstrated the interest being shown in applying this technology to monitoring the hydrographic patterns of large-scale basins worldwide. The current study presents the inference of time series representing changes in water le- vel for bodies of water by defining virtual gauge stations deduced for two very different rivers in terms of their biophysical and to- pographic characteristics; the two rivers were the Rio Negro in the Brazilian Amazon Basin and the Caqueta River on the Colombian side. The differences between the two rivers revealed the limits of satellite radar altimeter when applied to continental waters (±20cm and ±40 cm precision for Río Negro and Río Caquetá, respectively). However, applying this technology seems very promising, since new missions have been scheduled to be put into orbit by the end of 2008.

Keywords

• radar altimetry
• virtual gauge station
• altimetry time series
• hydrological modeling
• Amazon Basin