“NASA Study Reveals Alarming Loss of Salt Marshes and Impact on Climate Change”

NASA-led study reveals global loss of salt marshes, emitting significant carbon dioxide into the atmosphere

A new NASA-led study has uncovered a concerning trend of salt marsh loss around the world, with a total of 561 square miles (1,453 square kilometers) disappearing over the past two decades. This loss has significant implications for climate change, as marshes play a crucial role in sequestering carbon and protecting coastal communities.

Salt marshes are coastal grasslands that are regularly flooded by salty seawater. They serve as a vital indicator of climate change and provide essential protection against rising sea levels and severe storm impacts. Additionally, these ecosystems offer critical habitat for a variety of plant, animal, and bird species, as well as recreational opportunities for humans.

Lead author of the study, Anthony Campbell, emphasized the importance of salt marshes in storing carbon and the detrimental impact of their degradation on climate change. The study, which provided the first consistent global accounting of salt marsh locations and changes, estimated that 16.3 Terragrams of carbon dioxide were emitted into the atmosphere over the study period, equivalent to the annual emissions of approximately 3.5 million motor vehicles.

While some regions experienced gains in marshland, the overall global loss equated to two soccer fields disappearing every hour. The United States and Russia were identified as the primary contributors to marsh losses, accounting for 64% of the total decline.

Using satellite imagery from Landsat missions, NASA scientists conducted a comprehensive analysis of salt marsh changes, identifying key drivers such as storm events, urbanization, and sea-level rise. The resulting global salt marsh change data are now openly available, providing valuable insights for conservation efforts and policy-making.

Lola Fatoyinbo, a researcher at NASA’s Goddard Space Flight Center, highlighted the importance of blue carbon ecosystems like salt marshes in the global carbon budget. She emphasized the need for these ecosystems to be included in international climate policies, such as the Paris Agreement’s Nationally Determined Contributions (NDC), to effectively mitigate climate change.

As wetlands and marshes continue to face threats from climate-related drivers and coastal development, the protection and restoration of these ecosystems are crucial for achieving climate targets. The new global map of wetland losses and gains generated by this study could serve as a valuable tool for countries to prioritize conservation efforts and ensure the long-term sustainability of these critical ecosystems.