Why are we studying tropical forests?
Tropical forests cover less than 7% of Earth’s surface but exchange vast amounts of CO2, water, and energy with the atmosphere. They are the world’s most important land-based carbon sinks, helping to regulate the Earth’s climate. However, scientists are uncertain how tropical forests will respond to a warming climate and changing atmosphere, and if they will continue to act as a net carbon sink over the coming decades. Understanding the responses of tropical forests to global changes is critical for improving model projections of future climate.
What is NGEE-Tropics?
The Next-Generation Ecosystem Experiments–Tropics, or NGEE-Tropics, is a ten-year, multi-institutional project funded by the U.S. Department of Energy (DOE), Office of Science, Office of Biological and Environmental Research (BER). NGEE-Tropics aims to fill the critical gaps in knowledge of tropical forest-climate system interactions. The overarching goal of NGEE-Tropics is to develop a predictive understanding of how tropical forest carbon balance and climate system feedbacks will respond to changing environmental drivers over the 21st Century.
In our current Phase 2 of NGEE–Tropics, we are assessing what is known about tropical forest ecosystems and how well these processes are represented in Earth system models (ESMs). Uncertainty assessments are informing field and laboratory studies that will provide new, high-priority data for forest ecosystem models. Several initial field studies are underway at key sites, including pilot studies in Brazil, Panama, and Puerto Rico, and a select group of ForestGEO sites across the tropics. Measurements at these sites address:
• Forest carbon cycle−hydrology interactions
• Nutrient limitations in tropical secondary forests
• Plant functional diversity response to climate change
• Regional variation in the causes of tree mortality
The overarching goal of NGEE-Tropics is to develop a predictive understanding of how tropical forest carbon balance and climate system feedbacks will respond to changing environmental drivers over the 21st Century.
NGEE-Tropics’ grand deliverable is a representative, process-rich tropical forest ecosystem model, extending from bedrock to the top of the vegetative canopy-atmosphere interface, in which the evolution and feedbacks of tropical ecosystems in a changing climate can be modeled at the scale and resolution of a next-generation Earth System Model grid cell (~10 x 10 km2 grid size).