In September 2020, the Norwegian Government announced a contract providing public access to high-resolution satellite imagery of tropical forests.
Never has the public had open access to satellite imagery with such high spatial and temporal resolution. But what does this data windfall mean for forest monitoring? How will it contribute to our goals of reducing tropical deforestation and restoring forest landscapes?
Under this new contract, the earth imaging company Planet will provide free public access to 5-metre resolution satellite imagery covering the entire tropical forest region, to be updated monthly. Any person can view the mosaics—compilations of the clearest images taken the previous month— via websites like Global Forest Watch(GFW). More technically inclined users can download the data directly from Planet to conduct analyses and create derivative map products.
The contract is valued at US$43 million and is secured for a two-year period, with the possibility of extension for an additional two years. Existing forest monitoring systems, GFW included, rely primarily on freely available medium-resolution imagery (10-30 meter pixels) from NASA’s Landsat or the European Space Agency’s Sentinel programs. At this scale, we can detect with reasonable accuracy where forests are cleared, and— over longer time periods— where forests have grown back.
Landsat captures a complete picture of the Earth every eight days, although it may take many months or even years to capture a usable image in areas with high cloud cover, including many tropical rainforests.
At 5-meter resolution, we can see changes in forests on the scale of a single tree. Furthermore, Planet’s constellation of over 150 microsatellites image the entire Earth daily, which significantly increases the odds of capturing cloud-free images every month.
Imagery can be viewed on Global Forest Watch or be downloaded here.
Source: globalforestwatch
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