Spectral composition and quanta-to-energy ratio of diffuse photosynthetically active radiation under diverse cloud conditions
نویسندگان
چکیده
منابع مشابه
Estimation of photosynthetically active radiation under cloudy conditions
Clouds are the largest modulators of the solar radiative flux reaching the Earth’s surface. The amount and type of cloud cover prevailing at a given time and location largely determines the amount and type of solar radiation received at the Earth’s surface. This cloud radiative forcing is different for the different solar spectral bands. In this work, we analysed the influence of cloud radiativ...
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The efficiency with which incoming photosynthetically active radiation (PAR) is intercepted by a canopy depends on the proportions of diffuse and direct radiation in the incoming PAR. In the present work, we developed a comparison between two spectral cloudless sky parameterization schemes in terms of their capability to provide accurate estimates of global, diffuse and direct incoming PAR. Bot...
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Plant canopy interception of photosynthetically active radiation (PAR) drives carbon dioxide (CO2), water and energy cycling in the soil-plant-atmosphere system. Quantifying intercepted PAR requires accurate measurements of total incident PAR above canopies and direct beam and diffuse PAR components. While some regional data sets include these data, e.g. from Atmospheric Radiation Measurement (...
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Photosynthetically-active radiation is a necessary input in applications dealing with plant physiology, biomass production and natural illumination in greenhouses. Unfortunately, a worldwide routine network for the measurement of photosynthetically-active radiation is not yet established and it is often calculated as a constant ratio of the broadband solar radiation. This ratio is affected by m...
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ژورنال
عنوان ژورنال: Journal of Geophysical Research
سال: 2004
ISSN: 0148-0227
DOI: 10.1029/2003jd004251