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Overview | UV Data Partnership | UV Data Sites | Database | Analysis Software | References | Links | Home |
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The Solar Environmental Data Network (SOLARNET) is a partnership among the following Federal Government Agencies:
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National Institute of Standards and Technology (NIST), Gaithersburg, Maryland
- Service-Life Prediction Program at the Building and Fire Research Laboratory
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Smithsonian Institution, Environmental Research Center (SERC), Edgewater, Maryland
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U.S. Department of Agriculture, UV Monitoring Program, Ft. Collins, CO
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Forest Products Laboratory, U.S. Department of Agriculture, Madison, Wisconsin
Each agency is committed to various aspects of the operation and data analysis for the Solar UV Data Network. NIST oversees the program direction and its interest is in the management of data for determining the effects of UV spectra on the performance of building materials, such as coatings. SERC's interest in the data is represented by a long-term program in measuring the effects of UV spectra on biological species. SERC performs calibration services for the SR18 spectrophotometer, development and maintenance of the data acquisition software, and analysis of the spectral UV data. USDA, FLP's interest lies in evaluating the effect of UV spectra on wood products. The FLP in Madison, Wisconsin maintains a remote site for data acquisition. The program is supported by the NIST, Standard Reference Data Program whose mission is to provide value added data to the scientific community.
NIST Service-Life Prediction Program
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NIST is conducting basic and applied research to develop methods for predicting the performance and service life of polymeric building materials, such as protective coatings. Researchers at the Institute are investigating degradation mechanisms, improving characterization methods, and developing mathematical models of the degradation processes. Stochastic models, which are based in reliability theory and life-testing analysis, are included in the modeling efforts. |
NIST SPHERE (Simulated Photodegradation by High Energy Radiant Exposure) technology developed and patented by NIST researchers working on the Service Life Prediction of Polymer Coatings consortium. |
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To help in understanding the mechanisms of degradation and provide data for models, materials are characterized using many techniques to capture information regarding both chemical and physical degradation, including: |
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Image of the NIST SPHERE taken with a thermal camera. |
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Researchers also are developing improved ways to characterize atmospheric environments to which these materials are exposed. Characterization of environmental parameters that cause degradation is needed to link material properties with service life. The NIST work provides a strong scientific and technical basis for standards used by industry. The research is coordinated with voluntary standards organizations and trade associations, industry, and other federal agencies. |
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SERC (Smithsonian Environmental Research Program)
Smithsonian Photobiology
Research:
UV Impacts on Ecosystem Processes
One of the main biological impacts of UV exposure on plants is a reduction in the rate of photosynthesis. This can have a direct effect on plant primary productivity and, since different species may vary in their sensitivity to UV exposure, may eventually affect biodiversity. Research in the Photobiology Lab at SERC is focused on aquatic plants, particularly the suspended microalgae (phytoplankton) and benthic macroalgae (e.g. kelp).
Phytoplankton photosynthesis is inhibited by UV exposure, but impacts differ with wavelength. Short wavelength UVB is more effective than longer wavelengths of UVB; UVA is even less photoinhibiting (per unit exposure). These differential effects can be documented by measuring photosynthetic rates under defined experimental irradiances containing varying proportions of UVB, UVA and visible (photosynthetically active) irradiance. Given high resolution spectral measurements, a biological weighting function (or action spectrum) can be estimated for UV inhibition of photosynthesis. We have developed experimental methods for estimating biological weighting functions using environmentally realistic irradiance treatments (polychromatic exposures).
By defining the relative importance of UVB, UVA and visible irradiance in inducing photoinhibition for many types of phytoplankton, we are learning more about what factors control sensitivity to UVB damage. Within each species, UVB sensitivity is being related to factors such as growth rate, optical properties and chemical composition.
For more information, contact Dr. Patrick Neale.
Ecosystems under study include:
Chesapeake Bay and associated subestuaries (red tides)
Antarctica: Coastal environments (McMurdo, Palmer Station): Open Southern Ocean (Weddell Scotia Seas)
Arctic: Kelp communities at Resolute, NWT, Canada
Field studies in remote locations are supported by on-site operation of SR-18 radiometers, which provide high time resolution data to support evaluation of dose response relationships. The deployments also complement data sets of other monitoring instruments making higher spectral resolution, but less frequent measurements. In Antarctica, the SR-18 has been collocated with the NSF UV Network SUV-100 at Palmer Station. In the Arctic, our study area (location of the SR-18) was near the Brewer operated at Resolute by Environment Canada.
In the future, spectral techniques developed to study phytoplankton responses will be extended to other aquatic processes including bacterial growth and the photochemistry of dissolved organic compounds.
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The USDA UV-B Monitoring and Research Program is a program of the US Department of Agriculture's Cooperative State Research, Education and Extension Service (CSREES). The program was initiated in 1992, through a grant to Colorado State University, to provide information on the geographical distribution and temporal trends of UVB (ultraviolet -B) radiation in the United States. This information is critical to the assessment of the potential impacts of increasing ultraviolet radiation levels on agricultural crops and forests. Specifically the monitoring program:
- Provides information to the agricultural community and others about
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the climatological and geographical distribution of UVB irradiance;
- Furnishes the basic information necessary to support evaluations of
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the potential damage effects of UVB to agricultural crops and forests;
- Supplies ground truth for satellite measurements and basic information
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for radiation transfer model calculations;
- Establishes long-term records of UVB irradiance necessary to assess trends;
In a broader sense, the monitoring program supports research that increases our understanding of the factors controlling surface UVB irradiance and provides the data necessary for assessing the impact of UVB radiation on human health, ecosystems and materials.
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Wood Surface Chemistry
R. Sam Williams, Project Leader
This unit’s mission is to determine the basic mechanisms of deterioration of wood and wood-based composites used outdoors and to develop innovative technologies for modifying wood surfaces to enhance durability. This is achieved by developing the fundamental technical information needed to prevent the premature weathering failure and improve the weathering performance of wood, finished wood, and wood-based materials; by developing technical information about the wood surface needed to improve the performance of environmentally preferable water-based, water-repellent preservative technologies; and by developing fundamental information about wood surface chemistry, specifically on how surface coatings and wood interact.
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NIST - Standard Reference Data Program
For 30 years, the NIST Standard Reference Data Group (SRDG) has provided well-documented numeric data to scientists and engineers for use in technical problem-solving, research, and development. These recommended values are based on data which have been extracted from the world's literature, assessed for reliability, and then evaluated to select the preferred values. These data activities are conducted by scientists at NIST and in university data centers.
Standard Reference Data Group:
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John Rumble, Chief
john.rumble@nist.gov
(301) 975-2203
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