Small Temporal Baseline Subset Analysis (stbas): an Insar Technique for Multi-temporal Water Level Monitoring in Wetlands

We present an InSAR technique called Small Temporal Baseline Subset (STBAS) for monitoring absolute water levels time series using radar interferograms acquired successively over wetlands. We tested the STBAS technique with two-year long Radarsat-1 data acquired over the Water Conservation Area 1 (WCA1) in the Everglades wetlands, south Florida (USA). The fine beam SAR data were acquired successively every 24 days during the years 2006-2007 except for two missing acquisitions. The InSAR derived water level data were calibrated using 13 stage stations located in the study area to generate 28 successive high spatial resolution maps (50 meter pixel resolution) of absolute water levels. We evaluated the quality of our study by using a root mean square error (RMSE) analysis. The average RMSE is 6.6 cm, which provides an estimation of the STBAS technique to monitor absolute water levels.