This interferogram was created by combining two Sentinel-1A radar scenes from March 2 and March 14, 2015, over the Danube Delta in Romania, which covers more than 4,000 square kilometers and plays important roles in water supply and biodiversity.
As one of the Ramsar Convention’s wetlands of international importance and a UNESCO World Heritage Site, the delta has more than 30 different types of ecosystems that function as a natural buffer zone for pollutants from the Danube River.
The synthetic-aperture radar (SAR) Sentinel images, when combined, allow scientists to understand hydrological parameters such as water-surface extent, water-level changes, and the direction and gradients of water flow.
“The observed local behaviors proved to be much more complex than previously believed,” said Gheorghe Oaie, general director of GeoEcoMar, a Romanian research institute involved in the project. “Unprecedented detail could be gained on the normally unobservable connections between water bodies, making it possible to create local water-flow scenarios and improve on hydrological models.”