Chapter 4 Remote sensing and ground-based observations
This chapter focusses on the main types and sources of remotely-sensed and ground-based data used operationally for the estimation of emissions and removals associated with REDD+ activities. It includes advice on the use of pre-processed global data sets, particularly the UMD data provided via the Global Forest Watch. It describes the role of NFIs as a source of emissions and removals factors as well as for direct REDD+ estimation. Possibilities are identified for using intensive monitoring sites for model calibration, and the use of auxiliary information for data interpretation and augmentation is described. The chapter recognizes the roles of data in mapping and in providing reference data to correct for estimated bias and estimate precision, as set out in Chapter 5.