NASA DEVELOP

The Belize Barrier Reef is a biodiverse marine ecosystem and the largest coral reef system in the western hemisphere. The reef also provides ecosystem services in the form of fisheries and tourism and is estimated to be responsible for 12 to 15% of the nation’s gross domestic product. Retaining these ecosystem functions requires sustainable coastal management and preservation of water quality, especially in the face of global changes in climate and local anthropogenic impacts. The Belize Water Resources Team at NASA Jet Propulsion Laboratory and NASA Ames Research Center partnered with the Coastal Zone Management Authority and Institute, a Belizean governmental agency, and the Wildlife Conservation Society to evaluate water quality conditions and inform coastal management decisions. Using Google Earth Engine, we developed a tool that outputs a time series of sea surface temperature, turbidity, and chlorophyll-a concentration derived from Landsat 8 Operational Land Imager (OLI) and Sentinel-2 Multispectral Instrument (MSI), Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) and Terra MODIS satellite imagery. With optical data available from 2013 onward, our partners can efficiently identify reef areas threatened by depreciating water quality, designate Marine Protected Areas and no-take zones, and conduct temporal analyses of water quality changes following environmental disturbance events, such as hurricanes. Additionally, this tool will assist in identifying indicators that may be used to measure Belize’s progress towards Sustainable Development Goals regarding marine environments. Using the tool, partners can better monitor changing water quality and make decisions accordingly in regards to sustainable resource use, coral reef conservation practices, and environmental capital.

The Mesoamerican reef is a biodiverse ecosystem that stretches more than 600 miles along four Central American coasts and is the longest barrier reef in the western hemisphere. The national economies of Belize and Honduras heavily depend on the commercial, recreational, and subsistence fishing services the reef supplies. While the reef has benefitted from sustainable collaborative management practices, ecosystem stress resulting from the destruction of coastal habitats and overfishing threatens its diverse communities and ecological functions. The Belize & Honduras Water Resources II team at NASA Jet Propulsion Laboratory partnered with the Secretaría de Recursos Naturales y Ambiente (Honduras), the Comisión Centroamericana de Ambiente y Desarrollo, the Coastal Zone Management Authority and Institute (Belize), and the Wildlife Conservation Society to continue developing the Optical Reef and Coastal Area Assessment (ORCAA) tool in Google Earth Engine to monitor and evaluate water quality changes and advise coastal management decisions. The tool incorporates Earth observations from Landsat 8 Operational Land Imager (OLI), Sentinel-2 Multispectral Instrument (MSI), and Aqua and Terra Moderate Resolution Imaging Spectroradiometer (MODIS). ORCAA outputs maps and time series graphs of turbidity, sea surface temperature, chlorophyll-a, and colored dissolved organic matter concentrations from 2013 onward, which our partners will use to identify reef degradation, pass coastal resource regulations, and establish protected zones along the reef. These maps will better enable our partners to address declining water quality conditions through policy initiatives and maintain the environmental and economic health of the region.