A global map of open water bodies and coastlines at 150 m based on synergies between SAR and optical datasets

In the framework of the European Space Agency Climate Change Initiative, a global map of open water bodies and coastlines at 150 m resolution was derived using synthetic aperture radar and optical datasets including observations from the 2000-2012 period. This map and constitutive inputs were assessed qualitatively and quantitatively against a global reference validation database of 2110 samples, intentionally biased towards areas prone to errors in characterizing water bodies. It yielded more informative quality assessment figures in terms of the relative improvement between products and types of errors. The overall accuracy of the Climate Change Initiative global map of open water bodies at 150 m was found equal to 99% with a F-score of 89% for class water, significantly superior to its constitutive input water bodies datasets. The dataset is openly available at: http://maps.elie.ucl.ac.be/CCI/viewer since 2016.