The NASA Airborne Microwave Observatory of Subcanopy and Subsurface (AirMOSS) campaign focused on observations of root zone soil moisture (RZSM) and net ecosystem exchange (NEE) of carbon dioxide over a variety of North American biomes across several seasons. AirMOSS completed 34 deployments from 2012-2015, over parts of Canada, the US, and Costa Rica. Airborne observations included P-band synthetic aperture radar (SAR) measurements as well as carbon and other gas concentrations. AirMOSS supports NASA’s carbon cycle and ecosystems, climate, and Earth surface missions.
The AirMOSS P-band Radar is an airborne synthetic aperture radar (SAR) developed by the Jet Propulsion Laboratory (JPL). It was designed based on the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) L-band radar and has been a part of the UAVSAR instrument suite since the completion of the AirMOSS investigation in 2015. AirMOSS collects radar data to derive measurements of root-zone soil moisture, permafrost, and underground structures and subsurface changes. It operates across the 280-440 MHz frequency range and can detect up to 1.2 m below the land surface. AirMOSS has a slant range resolution of 7 m and a range swath width of 7 km at a nominal altitude of 12,500 m.
The Best Air Turbulence (BAT) probe is an in situ airborne wind sensor developed by NOAA. It is mounted on the front of an aircraft to make high-frequency wind measurements. The BAT probe measures the wind speed and direction with respect to the aircraft, while a complementary GPS and accelerometers measure the aircraft velocity with respect to the Earth. These measurements are combined to get the atmospheric pressure, temperature, and wind information at a sampling rate of 10 Hz. The BAT probe is typically mounted on aircraft but can be deployed on ships and vehicles.
The Picarro gas concentration analyzer is an in situ airborne or ground-based sensor manufactured by Picarro, Inc. It uses Wavelength-Scanned-Cavity Ring Spectroscopy (WS-CRDS) to measure trace gases such as carbon dioxide, carbon monoxide, methane, and water vapor. For carbon dioxide measurements, the laser within Picarro operates at 1603 nm wavelength and 1651 nm wavelength for methane and water vapor measurements. Picarro has a typical sampling time of 2.5 seconds. Depending on the model, Picarro can also provide measurements of carbon isotopes for gas concentrations.
FLUXNET is a global network of eddy covariance flux towers. Each tower is equipped with gas sensors to continuously measure the fluxes of trace gases such as carbon dioxide, methane, and water vapor between the land surface and the atmosphere. These towers are also equipped with various meteorological sensors to measure air temperature, precipitation, winds, radiation, and soil temperature. Currently, FLUXNET has over 250 flux tower sites across the globe in various vegetation types such as tundra, tropical, forest, and grasslands.
Earth Science > Land Surface > Soils > Soil Temperature
Rain gauges are ground-based instruments that provide in situ measurements of liquid precipitation amounts over a set time. There are multiple types of rain gauges that each collect and record data differently such as the tipping bucket rain gauge and weighing precipitation gauge. Rain gauges can be deployed in various locations due to their relatively small size and easy set-up and are typically colocated with other precipitation instruments such as disdrometers to provide more details about precipitation being collected such as precipitation rate and size distribution.
Earth Science > Spectral/engineering > Infrared Wavelengths > Brightness Temperature
Soil moisture probes are in situ ground-based sensors used to measure soil water content. The most common type of soil moisture probes used for scientific research use dielectric permittivity techniques such as capacitance sensors or time-domain reflectometry sensors. These types of probes measure the charge-storage capacity of the soil to determine the soil moisture content. They typically operate at frequencies around 50 MHz and above to reduce sensitivity to salinity. Soil moisture probes provide continuous measurements and are relatively easy to deploy.
The Best Air Turbulence (BAT) probe is an in situ airborne wind sensor developed by NOAA. It is mounted on the front of an aircraft to make high-frequency wind measurements. The BAT probe measures the wind speed and direction with respect to the aircraft, while a complementary GPS and accelerometers measure the aircraft velocity with respect to the Earth. These measurements are combined to get the atmospheric pressure, temperature, and wind information at a sampling rate of 10 Hz. The BAT probe is typically mounted on aircraft but can be deployed on ships and vehicles.
