AirMOSS

The overarching goal of the Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS) project is to significantly reduce the current uncertainty in net ecosystem exchange (NEE) estimates over North America. NEE is a key parameter for the carbon cycle that describes the difference between net primary production (NPP), which is the rate of carbon uptake through photosynthesis, and ecosystem respiration, which is the rate of carbon release.

AirMOSS will meet this challenge by providing high-resolution regional observations of Root Zone Soil Moisture (RZSM) over the major North American biomes. RZSM is defined here as the total moisture in the soil column from surface to the root zone. This benchmark dataset, the first of its kind, would be a major advancement over current point-scale RZSM measurements and provides carbon flux models a critical input parameter to create improved NEE estimates. By utilizing a succession hydrologic data assimilation and Ecosystem Demography model version-2 (ED2) we will investigate and quantify the impact of high-resolution RZSM on NEE estimation.

To measure RZSM, AirMOSS will build (from print) an ultra-high frequency (UHF) synthetic aperture radar (SAR) that has the capability to penetrate through substantial vegetation canopies and subsurface and retrieve information to the depths as large as 1.2m depending on the soil moisture content.