Open AccessLooking skyward to study ecosystem carbon dynamics
Author(s) -
Dye Dennis G.
Publication year - 2012
Publication title -
eos, transactions american geophysical union
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.316
H-Index - 86
eISSN - 2324-9250
pISSN - 0096-3941
DOI - 10.1029/2012eo140002
Subject(s) - radiance , environmental science , sky , atmosphere (unit) , aerosol , diffuse sky radiation , radiation , atmospheric sciences , remote sensing , sunlight , albedo (alchemy) , meteorology , geology , scattering , physics , astronomy , optics , art , performance art , art history
Between May and October 2011 the U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) program, conducted a field campaign at the ARM Southern Great Plains site in north central Oklahoma to evaluate a new instrument for quantitative image‐based monitoring of sky conditions and solar radiation. The High Dynamic Range All‐Sky Imaging System (HDR‐ASIS) was developed by USGS to support studies of cloud‐ and aerosol‐induced variability in the geometric properties of solar radiation (the sky radiance distribution) and its effects on photosynthesis and uptake of carbon dioxide (CO 2 ) by terrestrial ecosystems. Under a clean, cloudless atmosphere when the Sun is above the horizon, most of the solar radiation reaching an area of the Earth's surface is concentrated in a beam coming directly from the Sun; a relatively small proportion arrives as diffuse radiation from the rest of the sky. Clouds and atmospheric aerosols cause increased scattering of the beam radiation, which increases the proportion of diffuse radiation at the surface.