Observing Seasonality of Inundation Patterns Across the Pacaya-Samiria National Reserve Region Through the Use of Sentinel SAR 1

Wetlands, ecosystems seasonally or permanently inundated, play a major role in the Earth system, affecting biodiversity, hydrology, and meteorology. The Pacaya-Samiria National Reserve (PSNR) in Peru comprises one of the largest protected wetlands regions in the world. Located within the Amazon basin, the PSNR encompasses an area of more than 20,000 km², much of which is seasonally or perpetually inundated. The water-saturated soils lack oxygen for aerobic organisms to perform cellular respiration, leading to the release of large amounts of methane gas into the atmosphere by means of fermentation. Methane is a greenhouse gas that has been proven to be more threatening to our environment than carbon dioxide due to its high heat absorbency and associated greenhouse warming effect. Remote sensing satellites allow study of large expanses of difficult-to-access regions such as the PSNR. Time series remote sensing datasets support mapping of seasonal inundation patterns and comparative analyses with seasonal rainfall and river stage available from ground station networks. Time series imaging radar data from the European Space Agency’s Sentinel SAR are employed to assess seasonal variations in surface inundation. We compare these remote sensing datasets with ground measurements of river stage and precipitation collected by a network of meteorological and hydrological weather stations in the PSNR. The combination of the information from the ground stations and the radar imaging data support interpretation of seasonality of inundation patterns through means of direct comparison while supporting interpretation and validation of the derived remote sensing products. Results of this project will enhance our use of remote sensing imaging radar datasets for understanding of the role and impact of wetlands on global climate change.