We have modelled the baseline (1970-2000) and future (2050s, 2041-2060) habitat distribution across Africa for 127 tree species that were prioritized for the Provision of Adequate Tree Seed Portfolio in Ethiopia (PATSPO) project. The maps we developed for the 2050s correspond to two different scenarios: a low emissions scenario (Shared Socioeconomic Pathway SSP 1-2.6) and a high emissions scenario (SSP 3-7.0) projected by nine Global Climate Models (General Circulation Models) as available from WorldClim 2.1. The resolution of our maps is a 2.5 arc-minutes grid (~ 4.6 km at the equator), the highest level of detail that is available in WorldClim 2.1 for making future projections.

The choice of tree species' whose distributions we modelled was based on two main information sources. First, they were selected from a ‘top-96’ priority list of native and exotic tree species in Ethiopia that was developed for the PATSPO project (Kindt 2018). This list was expanded with further species native to Ethiopia that are listed in the Agroforestree database or Seed Leaflets series and that were part of a longer list of 240 candidate species in the report (Kindt 2018). 

Habitat suitability models were calibrated with ensemble suitability models via the BiodiversityR package in the R environment. A detailed description of methods used for creating the maps, such as how predictor variables were selected from an expanded set of bioclimatic, soil and topographic variables; on the compilation of occurrence observations; on the calibration of suitability models; and on the projections of habitat change in future climates, is given in an accompanying working paper (Kindt et al. 2023).

The attributes of tree species - such as growth form, reproductive biology and seed type - that are made available in our Atlas are a subset of the information available in a separate database compiled in parallel with the development of the maps (Lillesø, in prep.).

Our atlas is an output of the PATSPO project that is supported by Norway's International Climate and Forest Initiative through the Royal Norwegian Embassy in Ethiopia. Additional funding came from the CGIAR Research Program on Forests, Trees, and Agroforestry, supported by the CGIAR Trust Fund. PATSPO supports the Ethiopian government with the provision of high-quality tree planting material to meet its large forest restoration targets, while FTA is the world’s largest research-for-development programme focused on the role of forests, trees and agroforestry in sustainable development, food security and addressing climate change.