Estimates of aboveground carbon stocks are derived from a patchwork of methods that vary in quality and sampling density. Scientists lack consensus about the size of the forest carbon stock and the role of forests in the global carbon cycle. The NASA Global Ecosystem Dynamics Investigation (GEDI) was designed to overcome these challenges by placing a multibeam waveform lidar into low Earth orbit on the International Space Station. GEDI is a competitively selected NASA mission. It is producing globally representative measurements of the vertical distribution of vegetation in temperate and tropical forests, woodlands and savannas, and is the first spaceborne laser measurement system optimized for vegetation structure. The instrument successfully launched to the International Space Station in December, 2018 and began its nominal two-year mission life after in-orbit checkout early in 2019.
Quantifying carbon stocks using remote sensing requires statistical relationships between measured variables and field estimates of aboveground carbon density. Our approach to developing these models is data driven. We develop candidate models that are stratified by plant functional types and regions, and we evaluate models with varying numbers of predictors and transformations to identify the subset with the best performance.
The first public release of GEDI aboveground biomass density data will be in August, 2021.
Collaborators: Dr. Laura Duncanson (University of Maryland, College Park), Dr. John Armston (University of Maryland, College Park), and the GEDI Science Team.
Funding source: NASA