Version 2 of the CCI Biomass ATBD details the advances made in the retrieval methodology. A key development involves retrieving Above Ground Biomass (AGB) directly (rather than retrieving Growing Stock Volume and converting this to AGB). By reformulating the Water Cloud Model to include empirical parameters derived from height (and other) metrics the CCI Biomass team expect to see improved quality of the Year 2 products. The ATBD can be found here: Algorithm Theoretical Basis Document.