COASTAL ECOSYSTEM MAPPING
A GLOBALLY CONSISTENT MAP OF TIDAL MARSHES
Tidal marsh ecosystems are found on many of the world’s sheltered sediment-dominated coastlines, and consist of a variety of herbaceous and woody vascular plants. Tidal marshes are generally considered the characteristic vegetated intertidal ecosystem of temperate and arctic regions; however, they are an important, yet relatively overlooked, coastal feature in arid and tropical regions. The current global extent of tidal marshes is not well quantified, with estimates subject to large bounds of uncertainty. Further, owing to a lack of historical data on the distribution of tidal marshes, our understanding of the extent of tidal marsh loss is very limited, even for those more intensively studied areas. Here we address the lack of a tidal marsh extent baseline using high resolution satellite data and the cloud-based geospatial analysis platform Google Earth Engine. We hope that this analysis will provide the impetus for further research to quantify the ecosystem service value of tidal marshes and identify tidal marsh conservation and restoration opportunities.