Calculates country-level basic wood density (tDM per m3) based on IPCC 2006 Vol 4 Chapter 12 Table 12.4 values and Koeppen-Geiger climate classification. Density values: Tropical (A) = 0.59, Arid (B) = 0.52, Temperate (C) = 0.45, Continental (D) = 0.45, Polar (E) = 0.45.