
NGEE-Tropics will link model development with field research. Berkeley Lab’s Jeff Chambers conducting plant physiology and carbon cycle research at a site operated by Brazil’s National Institute of Amazonian Research and located north of Manaus, Brazil. Photo credit: Kolby Jardine
Tropical forests cycle more CO2 and water than any other biome, and play critical roles in determining Earth’s energy balance. Intact tropical forests are also estimated to be Earth’s largest carbon sink, yet the stability of this sink is susceptible to a warming climate and disturbance processes. Understanding of carbon and related water and energy exchanges between tropical forests and the atmosphere lags that of other biomes, and poor model representation of these processes is the most significant source of terrestrial uncertainty in projections of Earth’s future climate.
The 10-year vision for NGEE Tropics is to achieve dramatically reduced uncertainty in ESM projections, and increased scientific understanding of how tropical forest ecosystems will respond to climate and atmospheric change. An overall critical question is whether these forests will continue to offset a large fraction of anthropogenic carbon emissions in the 21st century or become carbon sources from vegetation die-back under a warming climate. Thus, 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.
The grand deliverable of NGEE Tropics is the development of a representative, process-rich tropical forest ecosystem model, extending from bedrock to the top of the vegetative canopy, in which the evolution and feedbacks of tropical ecosystems in a changing climate can be modeled at the scale/resolution of a next-generation Earth System Model grid cell (i.e., expected to be at least 10 x 10 km grid size). To achieve this goal, we will develop a new hierarchical, modular modeling platform that integrates crucial processes needed to represent tropical forest ecosystem responses to global changes, including belowground biogeochemistry, plant demography and ecophysiology, plant functional traits, and aquifer-to-canopy hydrology.
Model advances will be directly enabled by pantropical syntheses of existing data, and investments in high priority observations and experiments that enhance process representation, support model parameterization, and provide critical model benchmarks. These model functionalities have never been brought together into a single platform or rigorously evaluated against observations at a pantropical scale. Thus, NGEE Tropics will enable cutting-edge research advances toward addressing tropical forest response to a changing atmosphere and warming climate.
NGEE Tropics anticipates numerous productive collaborations and partnerships with tropical Earth system scientists to realize these goals.
NGEE Tropics is a Department of Energy (DOE) funded project lead by Berkeley Lab’s Earth & Environmental Sciences area.