More than half of all species live in tropical forests, which process five times as much carbon annually as humans emit from fossil fuel use. Tropical forests sustain societies, safeguard biodiversity, and help regulate the climate system. Their protection is needed to eliminate carbon emissions by 2050 and limit global warming to 1.5 degrees Celsius. As a result, there is an intense focus on slowing forest loss and restoring new forests. But there is a third, neglected piece of the puzzle: What is happening within remaining forests?  

In this lecture, Simon L. Lewis, Professor of Global Change Science at the University of Leeds and University College London, describes the role of remaining tropical forests in the contemporary Earth system over the past three decades. Using a pan-tropical network of long- term tropical forest inventory plots tracking over 2 million individual trees in 27 countries, Dr. Lewis demonstrates how intact tropical forests have been a globally significant factor in slowing climate change. However, there are hints that all is not well in the world’s last remote tropical forests, and Dr. Lewis also explores tropical forests’ potential to begin accelerating climate change in the future, a scenario that would impact us all.