Satellites: ambition for forest initiative

Full text (Correspondence is 300 words). Lynch et al. (Nature 496, 293-294; 2013) are surely right to say that satellites are essential for monitoring deforestation under the REDD+ provisions of a future climate agreement; indeed the need to use remotely sensed and ground based data in combination for this purpose was formally recognized by decision of the United Nations Framework on Climate Change Conference (UNFCCC) of Parties in 2009. What seems less likely is that a comprehensive rapid response monitoring system will, as Lynch et al. hope, be enshrined in international law under the UNFCCC at the 19th Conference of Parties, in Warsaw later this year. Nature is perhaps not the appropriate place to debate national sovereignty concerns, but these would represent a significant barrier to putting in place such a proposal. Cloud is also a constraint on optical remote sensing although screening and compositing methods can help reduce its effects. Radar can penetrate cloud but in our view is not yet established as an operational means for the capture of changes to forest ecosystems in the suitably systematic and repeatable manner required for monitoring deforestation although may become operationally relevant in the future. As participants in these processes we disagree strongly with the suggestion that the outputs of Global Observation of Forest and Land Cover Dynamics Programme (GOFC-GOLD) or the Global Forest Observations Initiative (GFOI) lack ambition and an understanding of the potential of satellites. On the contrary the aim of these activities is show objectively and without bias in favour of one approach or another how remote sensing helps systematic global monitoring to make REDD+ a reality, in the context of wider societal engagement and capacity building that are essential for its success.JRC.H.3-Forest Resources and Climat