Source: COLORADO STATE UNIVERSITY submitted to NRP
GLOBAL CHANGE/ULTRAVIOLET RADIATION, CO
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
0218488
Grant No.
2009-34263-19774
Cumulative Award Amt.
$1,312,660.00
Proposal No.
2009-03276
Multistate No.
(N/A)
Project Start Date
Aug 1, 2009
Project End Date
Jul 31, 2012
Grant Year
2009
Program Code
[HZ]- Global Change/Ultraviolet Radiation
Recipient Organization
COLORADO STATE UNIVERSITY
(N/A)
FORT COLLINS,CO 80523
Performing Department
Natural Resource Ecology Lab
Non Technical Summary
The UVMRP strives to meet the monitoring and modeling needs of its stakeholders. (1) High energy ultraviolet solar radiation can significantly damage plants, crops, animals, and ecosystems, alone or in combination with other environmental stress factors such as temperature and moisture. To address these concerns, in 1992 the USDA established the UV-B Monitoring and Research Program (UVMRP) at Colorado State University to provide cost-effective monitoring of UV-B levels over wide geographic areas of the United States. Most monitoring stations are located at USDA agricultural research facilities, or on University facilities with ties to USDA. Monitoring sites were selected to provide measurements useful for studies of national, regional, and local scope. This UVB Network is the only remaining US national monitoring effort for these wavelengths. This program provides high quality UVB data, dating back to 1995, which is publically available through the Internet. The UVMRP dataset is being used for agricultural research at the Agricultural Research Station at Beltsville, University of Maryland, Colorado State University, Mississippi State University, Purdue University, Cornell University, and the University of Nebraska; for health research at the University of California at Davis, University of Colorado Health Center and the University of Hawaii-Manoa; for education (including at several high schools), and at other universities and government agencies for a variety of projects. (2) The U.S. agriculture has been under severe stresses by frequent climate anomalies, threatening national food security. The threat is increasing and is made imminent as the earth?s climate is experiencing unequivocal, significant, and continuing changes. As a result of human activities, the concentration of atmospheric CO2 and other gases and particles continues increase with an unprecedented magnitude, possibly, as predicted by general circulation models, causing a global warming of 1.8-4.0 ?C at the end of this century. The warming is expected to accompany important shifts in precipitation distribution, and more frequent occurrences of cold/hot extremes and drought/flood events. Changes in these variables (CO2, temperature, precipitation, UV-B will alter plant growth, biomass, and community composition, which in turn affect water and nutrient cycling in and across ecosystems. Collectively, global changes in emissions and climate will likely have serious consequences on the terrestrial hydrology, ecosystem production, and water quality in the U.S. These components are intimately coupled in nature and should be modeled as such to assess their responses to global change. This proposed research will develop such an integrated modeling system for future credible assessment of food security, yield, and economic impact.
Animal Health Component
(N/A)
Research Effort Categories
Basic
100%
Applied
(N/A)
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
1320440207020%
2032499102010%
2022499108010%
1320430207015%
2030699102010%
2030799102010%
1020199107010%
6011719301015%
Goals / Objectives
GOALS-The UV-B Monitoring and Research Program (UVMRP) maintains two distinct and complementary program components.(1)The primary goal of the monitoring component is continued operation of the national UV-B monitoring network. Agricultural research scientists rely on the network's high quality data, data products, and services to support agricultural research describing the geographic distribution of UV-B solar irradiance, effects of increased or diminished UV-B on crops, native and invasive plants, and animals, and to facilitate the use of these measurements directly or as input to climate and crop models.(2) The goal of the program's modeling component is to develop an Integrated Agricultural Impact Assessment System that will couple a state-of-the-art regional climate model with comprehensive crop models to study climate-crop interactions and related economic impacts stemming from crop response to a wide range of stressors, including those associated with global climate change. Decision makers need reliable crop yield assessment tools to determine optimal cultural practices, assess risks and risk management strategies, and determine economic impacts. OBJECTIVES-(1)Effective and efficient operation of the UV-B network will be assured by adhering to the existing, proven methods of instrument servicing, data processing, and web-based data dissemination developed, enhanced, and refined over the past 16 years. Concurrently, work will continue to develop in-house instrument characterization capabilities, upgrade data processing algorithms and products, automate quality assurance checks, and consider next-generation instrumentation.(2) Development of the Integrated Agricultural Impact Assessment System is a large scale, multi-year effort that will integrate new and existing technology to meet objectives. First, to lay the foundation, a large volume of satellite and ground based data will be collected and assimilated. Second, the best, state-of-the-art climate and crop models will be improved, recoded, and optimized for integration. Third, quantitative, UVMRP supported, study-based crop stress modules and algorithms will be incorporated into crop models. And fourth, all components will be integrated into a system that will be validated as to its capability for providing relevant and credible crop yield and economic assessments for managers. EXPECTED OUTPUTS-(1)Solar irradiance data and data products collected from 37 monitoring sites in the United States, Canada, and New Zealand, will continue to be provided for near real-time viewing and data download on the UVMRP web site.(2)Valuable intermediary products will result from the development and validation of the numerous modeling modules to be integrated into the assessment system. These products, and the methodology behind them, will be reported in refereed journal articles and conference proceedings. Both the monitoring and modeling components of the UVMRP continue to be active in the scientific community. Last year project scientist's published 21 scientific papers in peer-reviewed journals, conference proceedings, and transactions while continuing to advise graduate and undergraduate students.
Project Methods
The UV-B Monitoring Network is comprised of 37 stations, each equipped with ultraviolet and visible solar radiometers. The network has been operational since 1993, providing high quality data necessary to determine climatology and variation of UV-B radiation.(1)The UVMRP will continue to use and enhance the mature and proven methods for operation of the network that have been developed and tested over many years. Methods and procedures exist for all facets of network operation: calibration and servicing of instruments; on-site maintenance and troubleshooting; and data collection, processing, management, and dissemination. Data integrity and security is of primary importance and is ensured through automated and manual quality control activities, the use of an extensive MySQL database, and implementation of the most current computer security measures in operation of the program's mature web site. The UVMRP continues to find methods to increase the efficiency of network operation: in-house instrument characterization capabilities are under development to assure uninterrupted collection of high quality data; data analysis algorithms are continually being developed to derive additional useful products from the measurements; and enhanced methods for web based data and data product dissemination are continually being deployed. Finally, looking to meeting the future needs of agricultural researchers, next-generation instrumentation and data products are being considered.(2) Several on-going experiments in growth chambers, green houses, and open fields will be continued to quantify the cross effects of UV-B radiation with other factors such as CO2, high temperature, and water stress on agricultural crops, trees, grasses, and ecosystems. Quantitative functional algorithms describing the UVB effects on phenomenological, growth, and physiological parameters of crop plants are being derived from the extensive experiments and incorporated into well-developed crop models.Enhancement of existing crop simulation models is underway to comprehensively study the impacts of UVB radiation, especially the combined effects with other abiotic and biotic factors, on crop growth, development, and yield.The crop models will also be coupled with regional climate models to evaluate the potential risks of climate change and UVB variation on the US agricultural production, and with economic models to assess financial impacts.Collaborations with scientists from other universities, research institutions, and government agencies are necessary to run this comprehensive and extensive monitoring and research program.We have established a good and efficient cooperative network in the US and throughout the world.The program will continue to develop this important crop yield and economic assessment tool.

Progress 08/01/09 to 07/31/12

Outputs
OUTPUTS: The UVMRP continues with its core objectives: 1) UV-B Monitoring and Research, which is a network of 40 climatological research stations in the United States, Canada, and New Zealand. An issue within the 48 states beyond our control is the problem of 'rural call completion', or more accurately non-completions, which has affected several of our rural sites causing significant loss of data cumulatively over time. To counter this problem and restore and maintain high data collection rates, we now have 13 sites converted to Internet-based polling, with more planned. For the instruments themselves we have instituted in-house instrument characterization of radiometric and spectral to date, with angular responsivity in progress. This includes the development of in-situ Langley calibration techniques which are now applied to all of the data we have available via the web site. 2) Continuous development of the regional Climate-Weather Research and Forecasting model (CWRF) coupled with the most-comprehensive crop growth models to study climate-crop interactions. In particular, we quantify the impacts of key environmental stress factors, including temperature, moisture, nutrient, UV radiation, CO2 concentration, aerosols, and other air pollutants, on agricultural crop quality and yields. This will facilitate model sensitivity studies to provide credible information on crop responses to regional climate variability and changes for decision makers to determine optimal cultural practices, assess potential risks, and identify risk management strategies. We found significant correlation between simulated and observed interannual variations across 87% of harvest grids. Included is an evaluation of the economic consequence at the national level from the predicted climate variability/change and associated crop responses, distributed at regional to local scales. It is this aggregate economic impact factor that is essential to facilitate policy decisions for agricultural production and management. The most important aggregate measure of the long-run health of the productive component of the agricultural economy is the measured agricultural total factor productivity (TFP). TFP in the US has experienced average growth of 1%-2% over the past 50 years, the variability of which is difficult to decompose into contributions from actual technical improvement or weather vulnerability. 3) Dissemination of Results: The UV-B Network data and data products, including spectral ultraviolet (UV) and visible radiation, erythemally weighted UV, photosynthetically active radiation (PAR), daily sums of UVA, UVB, erythemal irradiance, and Flint- and Caldwell-weighted biologically active irradiances are disseminated in near real-time, in tabular and graphic form, to a wide array of users via the program's web site, which is continually upgraded to keep pace with advances in web presence. The UVMRP website continues to be the primary vehicle for disseminating data and data products to stakeholders and researchers. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The UVMRP monitoring network continues to accumulate a valuable long-term (17+ years) record of surface UV-B and other solar irradiance measurements, working toward generation of realistic baseline levels of UV-B for comparison with future measurements. Improvement of the Integrated Climate-Crop Model continues. For input to the economic productivity module, high-resolution data, including temperature (daily maximum and minimum), precipitation, solar radiation, evaporation and crop yield, as well as their temporal characteristics (such as seasonal cycle and frequency distribution) has been obtained at the finest spatial scales available to best enable aggregations into specified regions (county, state, nation) that are required by the economic model for the total factor productivity (TFP) evaluation. This research will focus on developing a quantitative assessment of the US agricultural TFP, economic impacts, adaptation measures and policy changes in response to global climate change. The economic analysis of U.S. crop production pilot study initiated dialog between climate and economic scientists to develop potential synergies for better understanding and prediction of the complicated links between climate, agricultural productivity, and the economy. We achieved our goal to build an interdisciplinary bridge between physical crop and statistical economy modelers to advance prediction of climate change impacts on future US agricultural total factor productivity (TFP). As a result, we have prepared a list of major climate and crop variables for input to the economic productivity model. They include temperature, precipitation, solar radiation, evaporation, and crop yield, as well as their temporal characteristics (such as seasonal cycle and frequency distribution). The data for these variables were given at the finest spatial resolution available to enable aggregations into specified regions required by the economic model for productivity evaluation. We have also recruited one student who has a strong background in climate and more importantly essential knowledge of economy modeling and keen interest in policy related studies. We are now been well positioned to address bigger science problems: How does future US agricultural TFP change under global warming What are possible adaptation measures and mitigation policies that can capitalize future US crop production to the benefit of economy growth These questions will be the focus on our next phase research. The outcome of this research will lead to a quantitative assessment of the US agricultural TFP, economic impacts, adaptation measures and policy changes in response to global climate change. Calibration of the Monitoring Network instruments has become an in-house program due to reduced funding. Radiometric calibration is now routinely accomplished using comparison to known instruments at the world-renown Mauna Loa Observatory in Hawaii. Spectral calibration measurements are underway in our lab at the CSU office, though additional work is required to refine these measurements to a level acceptable to scientific users. Angular calibration capability is concurrently under development.

Publications

  • Liang, X.Z., M. Xu, W. Gao, K.R. Reddy, K. Kunkel, D.L. Schmoldt and A.N. Samel. 2012. Physical modeling of U.S. cotton yields and climate stresses during 1979-2005. Agronomy Journal, 104:675-683


Progress 08/01/10 to 07/31/11

Outputs
OUTPUTS: The UVMRP remains focused on its core objectives: 1) UV-B Monitoring and Research: High data collection rates continue to be maintained throughout the network of 40 climatological and research stations in the United States, Canada, and New Zealand. Additional sites continue to be converted to Internet-based polling to help maintain high data collection rates. To assure measurement accuracy, the network staff continues to improve our internal, in-house instrument characterization (radiometric, spectral, and angular responsivities) including the development of in-situ Langley calibration techniques. 2) Development of an Integrated Climate-Crop Model : A study to quantify effects of UV-B radiation on crop growth and development for use in the modeling project has these three objectives: A) test the hypothesis that elevated UV-B and other factors such as low temperature will modify the response of transpiration, carbon acquisition, growth and development of crops (cotton, peanut and sorghum) during seedling establishment; B) test the hypothesis that elevated CO2 will ameliorate the deleterious effects of UV-B and low temperature stress effects on crops; C) understand the physiological and biochemical basis of these responses to multiple stress factors either alone or in combination and their interactions on major crops grown in the USA and in tropical conditions. 3) Dissemination of Results: The UV-B Network data and data products, including spectral ultraviolet (UV) and visible radiation, erythemally weighted UV, photosynthetically active radiation (PAR), daily sums of UVA, UVB, erythemal irradiance, and Flint- and Caldwell-weighted biologically active irradiances are disseminated in near real-time, in tabular and graphic form, to a wide array of users via the program's web site, which was recently upgraded to keep pace with advances in web design. The UVMRP website continues to be the primary vehicle for disseminating data and data products to stakeholders and researchers. Our senior scientist chaired one international conference and our research scientists published two scientific papers in peer-reviewed journals, proceedings and transactions. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The UVMRP monitoring network continues to generate a valuable, long-term (17+ years) record of surface UVB measurements. Improvement of the Integrated Climate-Crop Model continues. We have developed a dynamic and statistical parameterization of surface albedo for snow-free land by optimizing MODIS direct and diffuse albedo in two bands (visible and near-infrared) with AVHRR vegetation cover fraction and type, MODIS LAI product and North American Land Data Assimilation System (NDLAS) top soil layer moisture data. Since the end of 2007, MODIS data products have combined the observations from both Aqua and Terra satellites, with numerous updates in the retrieval algorithm, and have been released for public use. The quality of this new data is significantly improved compared the products used in Liang et al. (2005b)'s study. Moreover, the North American Regional Reanalysis (NARR) data (Mesinger et al., 2006) has been available and it provides good estimations of top soil layer moisture to be used in albedo parameterization. The recent updates are essential for the crop modeling especially since we find that the big changes are most relevant to croplands. Hence, we re-optimized the surface albedo using MODIS LAI and albedo products in long period (~11 years) and short composite days (8 days), and advanced the regional reanalysis soil moisture data from NARR. To be consistent with the MODIS LAI and albedo, the vegetation cover and type are also derived from MODIS vegetation cover product (MCD12Q1) in our optimizations. The results indicate that the albedo calculated by the old CLM scheme is much worse than that in Liang et al. (2005b), because more data are used in current comparison. However, the re-optimized new scheme still has comparative performance across nearly all vegetation covers. The reduction in correlation coefficient for tree types using the visible albedo may be due to the uncertainty of MODIS products.Continue to further develop and improve the coupled modeling system for crop-climate interactions, to accurately model the surface UV radiation by assimilating the latest satellite observations into the numerical models. Immediate tasks include: 1) incorporating the MODIS products into the Modularized Tropospheric Ultraviolet and Visible (TUV) Radiation Model (MTUV) to predict UV ratio under all-sky conditions, 2) improving the consistency of the CWRF-GOSSYM coupled modeling system, and 3) implementing the DSSAT-CERES-maize model into CWRF. Calibration of the Monitoring Network instruments has become an in-house program due to the reduced funding. Currently radiometric calibration is accomplished using comparison to known instruments at the world-renown Mauna Loa Observatory in Hawaii. Spectral calibration capability is nearing completion in our lab at the CSU office, with angular calibration capability concurrently under development.

Publications

  • Gao, Z. and W. Gao. 2010. Comparative analysis of UVB exposure between Nimbus 7/TOMS satellite estimates and ground-based measurements. Remote Sensing and Modeling of Ecosystems for Sustainability VII, edited by Wei Gao, Thomas J. Jackson and Jinnian Wang, Proc. of SPIE, Vol. 7809, 78090Q-1, doi: 10.1117/12.858452
  • Singh, S.K., V.G. Kakani, G.K. Surabhi, and K.R. Reddy. 2010. Cowpea (Vigna unguiculata [L] Walp.) genotypes response to multiple abiotic stresses. Journal of Photochemistry and Photobiology B: Biology 100:135-146


Progress 08/01/09 to 07/31/10

Outputs
OUTPUTS: The UVMRP remains focused on its core objectives: 1) UV-B Monitoring and Research: High data collection rates continue to be maintained throughout the network of 40 climatological and research stations in the United States, Canada, and New Zealand. Additional sites continue to be converted to Internet-based polling to help maintain high data collection rates. To assure measurement accuracy, the network staff continues to improve our internal, in-house instrument characterization (radiometric, spectral, and angular responsivities) including the development of in-situ Langley calibration techniques. 2) Development of an Integrated Climate-Crop Model : A study to quantify effects of UV-B radiation on crop growth and development for use in the modeling project has these three objectives: A) test the hypothesis that elevated UV-B and other factors such as low temperature will modify the response of transpiration, carbon acquisition, growth and development of crops (cotton, peanut and sorghum) during seedling establishment; B) test the hypothesis that elevated CO2 will ameliorate the deleterious effects of UV-B and low temperature stress effects on crops; C) understand the physiological and biochemical basis of these responses to multiple stress factors either alone or in combination and their interactions on major crops grown in the USA and in tropical conditions. To full fill these objectives, a controlled environment study was conducted in sunlit growth chambers to determine the effects of UV-B radiation, elevated CO2, and temperature on three tropical crops of cotton, peanut and sorghum. The experiment was conducted in sunlit controlled environment chambers known as SPAR (Soil-Plant-Atmosphere-Research) facility at Mississippi State University's Plant Science Research Center. These computer-controlled chambers permit the determination of quantifiable results needed for the development of the integrated climate-crop model. 3) Dissemination of Results: The UV-B Network data and data products, including spectral ultraviolet (UV) and visible radiation, erythemally weighted UV, photosynthetically active radiation (PAR), daily sums of UVA, UVB, erythemal irradiance, and Flint- and Caldwell-weighted biologically active irradiances are disseminated in near real-time, in tabular and graphic form, to a wide array of users via the program's web site, which was recently upgraded to keep pace with advances in web design. Our senior scientist chaired one international conference and our research scientists published two scientific papers in peer-reviewed journals, proceedings and transactions. The UVMRP website continues to be the primary vehicle for disseminating data and data products to stakeholders and researchers. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Not relevant to this project.

Impacts
The UVMRP monitoring network continues to generate a valuable, long-term record of surface UVB measurements. A recent study analyzed UVB flux over the continental USA using NASA TOMS data and UVMRP network data and found that ground-based in-situ measurements, like those from the UVMRP network, are indispensible in monitoring atmospheric status and not totally replaceable by space-based remote sensing retrievals. Current satellite retrieval algorithms for average aerosol optical depth and air pollution data now have better accuracy due to this intensive cross-validation from ground-based UV measurements and these new post-calibration methods have improved UV retrievals for the latest satellite package (OMI). A second paper presents a new drought assessment method by spatially and temporally integrating temperature vegetation dryness index (TVDI) with regional water stress index (RWSI) based on a synergistic approach. A drought impact assessment for 1987-2000 linked RWSI with TVDIs group wise and determined: land surface temperature and vegetation indices were negatively correlated in most cases of low, medium and high vegetation cover except for high density vegetation cover in 2000 from urban heat island effect; shortage of water in 1987 was more salient than in 2000 based on all indices of TVDI and RWSI; and TVDIs are more suitable for monitoring mild drought, normal and wet conditions when RWSI is smaller than 0.752 but they are not suitable for monitoring moderate and severe drought conditions. A third study at Mississippi State University, using computer-controlled sunlit growth chambers, quantified effects of UVB and other environmental stressors on cotton, peanut and sorghum and developed algorithms for use in the integrated climate-crop modeling program. These results have been presented at scientific conferences. Photosynthesis and stomatal conductance exhibited considerable variability among the crops and treatments. A similar pattern was observed in transpiration rate. On average, low temperature decreased net photosynthesis by 30%; however, the addition of CO2 increased the response by 5%. Sorghum was the most sensitive crop to low temperatures. On average, the low temperature treatment transpiration rates were 60% lower than the control. Low temperature suppressed total chlorophyll content; however, carotenoid levels increased. Plants grown under elevated CO2 showed lower injury while low temperature and elevated CO2 treatment combinations increased the damage to the cell membranes. Maximum relative injury (75%) was observed in cotton exposed to low temperature stress. The average chlorophyll stability index ranged from 70 to 80% in all treatment combinations. In summary, low temperature suppressed photosynthesis and vegetative growth processes, and showed more damage to cell membranes compared to optimum conditions. The beneficial effects of elevated CO2 on photosynthesis and growth processes at these treatment conditions either alone or in combination were not uniform or appears to be species-dependent.

Publications

  • Gao, Z.Q., W. Gao, and N.B. Chang. 2010. Comparative Analyses of Ultraviolet-B Flux over the Continental US with NASA TOMS Data and USDA Ground-based Measurements. Journal of Applied Remote Sensing, Vol. 4, 043547, doi: 10.1117/1.3507249
  • Gao, Z. Q., W. Gao, N. Chang. 2010. Integrating Satellite-based Temperature Vegetation Dryness Index (TVDI) with Regional Water Stress Index (RWSI) for Drought Impact Assessment in a Developed Coastal Region. International Journal of Applied Earth Observation and Geoinformation, doi:10.1016/j.jag.2010.10.005