Over recent decades, significant changes in the extent and composition of mangroves in response to environmental change have been observed in mangrove ecosystems worldwide. With the predicted climate changes forecast for this century, including sea level rise, increasing temperatures and storm activity, acceleration in the natural processes of change may occur. Furthermore, direct clearance of mangroves and conversion of mangrove to other land uses, including in particular aquaculture, is occurring at an alarming rate and, in many cases, the extent of clearance is unknown.

The Global Mangrove Watch (GMW) was originally formed as part of the JAXA Kyoto & Carbon initiative and aims to:

  • Generate revised baseline maps of mangrove extent in the tropics and subtropics for 2010 and 2015.
  • Map changes relative to existing pan-tropical and subtropical mangrove baseline data sets using mid-1990’s JERS-1 SAR data, ALOS PALSAR data acquired in 2007, 2008, 2009 and 2010 and ALOS-2 PALSAR-2 annually from 2015 onwards.
  • Undertake routine monitoring of mangroves.
  • Provide validation of the products through reference to field and other remote sensing acquisitions for key sites worldwide.
  • Describe and understand the causes and consequences of change, whether natural or anthropogenic.
  • Contribute to the Ramsar Global Wetlands Observing System (GWOS).

The Global Mangrove Watch (GMW) is a collaboration between Aberystwyth University (U.K.), solo Earth Observation (soloEO; Japan), Wetlands International the World Conservation Monitoring Centre (UNEP-WCMC) and the Japan Aerospace Exploration Agency (JAXA).