Aerosol Optical Thickness Measurements During the Forest Ecosystem Dynamics - Multisensor Aircraft Campaign

Forest Ecosystem Dynamics Multisensor Airborne Campaign (FED MAC):
Aerosol Optical Thickness

The Biospheric Sciences Branch (formerly Earth Resources Branch)
within the Laboratory for Terrestrial Physics at NASA's Goddard Space
Flight Center and associated University investigators are involved in
a research program entitled Forest Ecosystem Dynamics (FED) which is
fundamentally concerned with vegetation change of forest ecosystems at
local to regional spatial scales (100 to 10,000 meters) and temporal
scales ranging from monthly to decadal periods (10 to 100 years). The
nature and extent of the impacts of these changes, as well as the
feedbacks to global climate, may be addressed through modeling the
interactions of the vegetation, soil, and energy components of the
boreal ecosystem.

Measurement of atmospheric attenuation and hence estimate of the
aerosol optical thickness were made in the Northern Experimental
Forest (NEF) in Howland, Maine, with sunphotometers. This parameter is
useful in calibration and correction of other measurements made with
remote sensing instruments at FED sites. Measurements were made with the
eight channel sun-photometer named SXM-2 (440, 522, 613, 672, 781, 871
and 1030 nm with 10 nm FWHM) located on the ground. It tracks the
sun automatically using a 4 quadrant detector. The detector is a
silicon photodiode which is kept at a constant temperature. The
instrument has a 1.5 degree field-of-view.

The FED Home Page is at: "https://forest.gsfc.nasa.gov/".