Global Wetting by Seasonal Surface Water Over the Last Decades

• Main Authors: Sonia Borja, Zahra Kalantari, Georgia Destouni
• Format: Article
• Language: English
• Published: American Geophysical Union (AGU) 2020-03-01
• Series: Earth's Future
• Subjects: surface water; global hydrology; seasonal surface water; water area change
• Online Access: https://doi.org/10.1029/2019EF001449

Abstract Surface water bodies and their changes in the landscape are critical for societies and ecosystems. However, the global change in surface water area over the last decades remains unclear, as recent studies using the same satellite data disagree on its direction. Here, we reanalyze reported maps of global water classification based on that data in order to estimate the changes in long‐term average surface water area from the first (1985–2000) to the second (2001–2015) half of the recent 30‐year period (1985–2015). We find a net gain in global surface water area by 100,454 km2, primarily due to seasonal water gains (83,329 km2). Over the world, we identify net wetting in 187 and net drying in 57 regional hydrological catchments, with the greatest water gain in Sabarmati (India) and loss in Amu Darya (Uzbekistan). We provide an interactive map to further explore the highly heterogeneous local changes around the world.