Assessing the non-local Climate impacts of Tropical deforestation (ACT)

Rapid deforestation is occurring across the tropics with substantial impacts on local and regional climate including increased temperature and reduced precipitation. Whilst there is now strong evidence of the local climate impacts of deforestation, there is very limited understanding of how deforestation alters the climate at distances of tens to hundreds of km from the location of forest loss. These non-local climate impacts are challenging to assess and are poorly constrained, but have important impacts on the lives of millions of people living across tropical forest regions. Our analysis of satellite data has shown that regions of the Brazilian Amazon with both local and regional deforestation have experienced four times greater land-surface warming than regions with only local forest loss, suggesting that non-local impacts are substantial. We will use a novel combination of satellite remote sensing, machine learning and regional climate models to make the first detailed assessment of the non-local impacts of tropical deforestation on climate. We will apply machine learning methods to isolate the local and non-local climate impacts of forest loss in satellite records of temperature and precipitation. We will use a regional climate model with embedded water vapour tracking to assess how deforestation alters water fluxes, regional water budgets and climate. We will quantify the regional climate impacts of policy relevant scenarios and interventions identified through our network of tropical forest stakeholders. This work will transform our understanding of how deforestation alters regional climate and will ensure new results support evidence-based sustainable land use in the tropics.