32 results on '"Luvall, J. C."'
Search Results
2. Field Scale Mapping of Surface Soil Clay Concentration
- Author
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Chen, Feng, Kissel, David E., West, Larry T., Adkins, W., Clark, Rex, Rickman, Doug, and Luvall, J. C.
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- 2004
- Full Text
- View/download PDF
3. Use of MODIS Satellite Data to Evaluate Juniperus spp. Pollen Phenology to Support a Pollen Dispersal Model, PREAM, to Support Public Health Allergy Alerts
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Luvall, J. C, Sprigg, W. A, Levetin, E, Huete, A, Nickovic, S, Prasad, A, Pejanovic, G. A, Vukovic, A, VandeWater, P. K, Budge, A. M, Hudspeth, W, Krapfl, H, Toth, B, Zelicoff, A. P, Myers, O. B, Bunderson, L, Ponce-Campos, G, Crimmins, T. M, Menache, M, and Vujadinovic, M
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Geophysics - Abstract
Pollen can be transported great distances. Van de Water et. al., 2003 reported Juniperus spp. pollen was transported 200-600 km. Hence local observations of plant phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. The DREAM (Dust REgional Atmospheric Model) is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and concentrations of dust. We are modifying the DREAM model to incorporate pollen transport. Pollen emission is based on MODIS-derived phenology of Juniperus spp. communities. Ground-based observational records of pollen release timing and quantities will be used as model verification. This information will be used to support the Centers for Disease Control and Prevention s National Environmental Public Health Tracking Program and the State of New Mexico environmental public health decision support for asthma and allergies alerts
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- 2013
4. Use of MODIS Satellite Data to Evaluate Juniperus spp. Pollen Phenology to Support a Pollen Dispersal Model, PREAM, to Support Public Health Allergy Alerts
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Luvall, J. C, Sprigg, W, Levetin, E, Huete, A, Nickovic, S, Pejanovic, G. A, Vukovic, A, VandeWater, P, Budge, A, Hudspeth, W, Krapfl, H, Toth, B, Zelicoff, A, Myers, O, Bunderson, L, Ponce-Campos, G, Crimmins, T, and Menache, M
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Life Sciences (General) - Abstract
Juniperus spp. pollen is a significant aeroallergen that can be transported 200-600 km from the source. Local observations of Juniperus spp. phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. Methods: The Dust REgional Atmospheric Model (DREAM)is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and quantities of dust. We successfully modified the DREAM model to incorporate pollen transport (PREAM) and used MODIS satellite images to develop Juniperus ashei pollen input source masks. The Pollen Release Potential Source Map, also referred to as a source mask in model applications, may use different satellite platforms and sensors and a variety of data sets other than the USGS GAP data we used to map J. ashei cover type. MODIS derived percent tree cover is obtained from MODIS Vegetation Continuous Fields (VCF) product (collection 3 and 4, MOD44B, 500 and 250 m grid resolution). We use updated 2010 values to calculate pollen concentration at source (J. ashei ). The original MODIS derived values are converted from native approx. 250 m to 990m (approx. 1 km) for the calculation of a mask to fit the model (PREAM) resolution. Results: The simulation period is chosen following the information that in the last 2 weeks of December 2010. The PREAM modeled near-surface concentrations (Nm-3) shows the transport patterns of J. ashei pollen over a 5 day period (Fig. 2). Typical scales of the simulated transport process are regional.
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- 2012
5. Assessing the Association Between Asthma and Air Quality in the Presence of Wildfires
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Young, L. J, Lopiano, K. K, Xu, X, Holt, N. M, Leary, E, Al-Hamdan, M. Z, Crosson, W. L, Estes, M. G, Luvall, J. C, Estes, S. M, DuClos, C, Jordan, M, and Gotway, C. A
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Environment Pollution - Abstract
Asthma hospital/emergency room (patient) data are used as the foundation for creating a health outcome indicator of human response to environmental air quality. Daily U.S. Environmental Protection Agency (EPA) Air Quality System (AQS) fine particulates (PM2.5) ground data and the U.S. National Aeronautical Space Administration (NASA) MODIS aerosol optical depth (AOD) data were acquired and processed for years of 2007 and 2008. Figure 1 shows the PM2.5 annual mean composite of all the 2007 B-spline daily surfaces. Initial models for predicting the number of weekly asthma cases within a Florida county has focused on environmental variables. Weekly maximums of PM2.5, relative humidity, and the proportions of the county with smoke and fire were the environmental variables included in the model. Cosine and sine functions of time were used to account for seasonality in asthma cases. Counties were considered to be random effects, thereby adjusting for differences in socio ]demographics and other factors. The 2007 predictions for Miami ]Dade county when using B ]splines PM2.5 are displayed in Figures 2.
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- 2012
6. Aerobiology of Juniperus ashei Pollen in Texas and Oklahoma: 647
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Levetin, E., Bunderson, L., Van de Water, P., and Luvall, J. C.
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- 2011
7. Use of MODIS Satellite Images and an Atmospheric Dust Transport Model To Evaluate Juniperus Spp. Pollen Phenology and Dispersal to Support Public Health Alerts: 59
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Luvall, J. C., Sprigg, W., Levetin, E., Huete, A., Nickovic, S., Pejanovic, G., Van de Water, P., Myers, O., Budge, A., Crimmins, T., Krapfl, H., and Zelicoff, A.
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- 2011
8. Use of MODIS Satellite Images and an Atmospheric Dust Transport Model to Evaluate Juniperus spp. Pollen Phenology and Transport
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Luvall, J. C, Sprigg, W. A, Levetin, E, Huete, A, Nickovic, S, Pejanovic, G. A, Vukovic, A, Van de Water, P. K, Myers, O. B, Budge, A. M, Zelicoff, A. P, Bunderson, L, Ponce-Campos, G, and Crimmins, T. M
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Earth Resources And Remote Sensing - Abstract
Pollen can be transported great distances. Van de Water et al., 2003 reported Juniperus spp. pollen, a significant aeroallergen was transported 200-600 km. Hence local observations of plant phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. Direct detection of pollen via satellite is not practical. A practical alternative combines modeling and phenological observations using ground based sampling and satellite data. The DREAM (Dust REgional Atmospheric Model) is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and quantities of dust (Nickovic et al. 2001). The use of satellite data products for studying phenology is well documented (White and Nemani 2006). In the current project MODIS data will provide critical input to the PREAM model providing pollen source location, timing of pollen release, and vegetation type. We are modifying the DREAM model (PREAM - Pollen REgional Atmospheric Model) to incorporate pollen transport. The linkages already exist with DREAM through PHAiRS (Public Health Applications in Remote Sensing) to the public health community. This linkage has the potential to fill this data gap so that the potential association of health effects of pollen can better be tracked for possible linkage with health outcome data which may be associated with asthma, respiratory effects, myocardial infarction, and lost workdays. Juniperus spp. pollen phenology may respond to a wide range of environmental factors such as day length, growing degree-days, precipitation patterns and soil moisture. Species differences are also important. These environmental factors vary over both time and spatial scales. Ground based networks such as the USA National Phenology Network have been established to provide national wide observations of vegetation phenology. However, the density of observers is not adequate to sufficiently document the phenology variability over large regions. Hence the use of satellite data is critical to observe Juniperus spp. pollen phenology. MODIS data was used to observe Juniperus spp. pollen phenology. The MODIS surface reflectance product(MOD09) provided information on the Juniper spp. cone formation and cone density (Fig 1). Ground based observational records of pollen release timing and quantities were used as verification. Techniques developed using MOD09 surface reflectance products will be directly applicable to the next generation sensors such as VIIRS.
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- 2011
9. Use of MODIS Satellite Images and an Atmospheric Dust Transport Model To Evaluate Juniperus spp. Pollen Phenology and Dispersal
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Luvall, J. C, Sprigg, W. A, Levetin, Estelle, Huete, Alfredo, Nickovic, S, Pejanovic, G. A, Vukovic, A, VandeWater, P. K, Myers, O. B, Budge, A. M, Zelicoff, A. P, Bunderson, L, and Crimmins, T. M
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Earth Resources And Remote Sensing - Abstract
Pollen can be transported great distances. Van de Water et. al., 2003 reported Juniperus spp. pollen was transported 200-600 km. Hence local observations of plant phenology may not be consistent with the timing and source of pollen collected by pollen sampling instruments. The DREAM (Dust REgional Atmospheric Model, Nickovic et al. 2001) is a verified model for atmospheric dust transport modeling using MODIS data products to identify source regions and quantities of dust. We are modifying the DREAM model to incorporate pollen transport. Pollen release will be estimated based on MODIS derived phenology of Juniperus spp. communities. Ground based observational records of pollen release timing and quantities will be used as verification. This information will be used to support the Centers for Disease Control and Prevention's National Environmental Public Health Tracking Program and the State of New Mexico environmental public health decision support for asthma and allergies alerts.
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- 2011
10. Benefits of Using Remote Sensing for Health Alerts and Chronic Respiratory Exposures
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Luvall, J. C
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Earth Resources And Remote Sensing - Abstract
Respiratory diseases such as asthma can be triggered by environmental conditions that can be monitored using Earth observing data and environmental forecast models. Frequent dust storms in the southwestern United States, the annual cycle of juniper pollen events in the spring, and increased aerosol and ozone concentrations in summer, are health concerns shared by the community at large. Being able to forecast the occurrence of these events would help the health care community prepare for increased visits to emergency rooms, as well as allow public health officials to issue alerts to affected persons. This information also is important to epidemiologists for analyzing long-term trends and impacts of these events on the health and well-being of the community. Earth observing data collected by remote sensing platforms are important for improving the performance of models that can forecast these events, and in turn, improve products and information for decision-making by public health authorities. This presentation will discuss the benefits of using remote sensing data for forecasting environmental events that can adversely affect individuals with respiratory ailments. The presentations will include a brief discussion on relevant Earth observing data, the forecast models used, and societal benefits of the resulting products and information. Several NASA-funded projects will be highlighted as examples
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- 2010
11. Effects of Solar Photovoltaic Panels on Roof Heat Transfer
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Dominguez, A, Klessl, J, Samady, M, and Luvall, J. C
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Mechanical Engineering - Abstract
Building Heating, Ventilation and Air Conditioning (HVAC) is a major contributor to urban energy use. In single story buildings with large surface area such as warehouses most of the heat enters through the roof. A rooftop modification that has not been examined experimentally is solar photovoltaic (PV) arrays. In California alone, several GW in residential and commercial rooftop PV are approved or in the planning stages. With the PV solar conversion efficiency ranging from 5-20% and a typical installed PV solar reflectance of 16-27%, 53-79% of the solar energy heats the panel. Most of this heat is then either transferred to the atmosphere or the building underneath. Consequently solar PV has indirect effects on roof heat transfer. The effect of rooftop PV systems on the building roof and indoor energy balance as well as their economic impacts on building HVAC costs have not been investigated. Roof calculator models currently do not account for rooftop modifications such as PV arrays. In this study, we report extensive measurements of a building containing a flush mount and a tilted solar PV array as well as exposed reference roof. Exterior air and surface temperature, wind speed, and solar radiation were measured and thermal infrared (TIR) images of the interior ceiling were taken. We found that in daytime the ceiling surface temperature under the PV arrays was significantly cooler than under the exposed roof. The maximum difference of 2.5 C was observed at around 1800h, close to typical time of peak energy demand. Conversely at night, the ceiling temperature under the PV arrays was warmer, especially for the array mounted flat onto the roof. A one dimensional conductive heat flux model was used to calculate the temperature profile through the roof. The heat flux into the bottom layer was used as an estimate of the heat flux into the building. The mean daytime heat flux (1200-2000 PST) under the exposed roof in the model was 14.0 Watts per square meter larger than under the tilted PV array. The maximum downward heat flux was 18.7 Watts per square meters for the exposed roof and 7.0 Watts per square meters under the tilted PV array, a 63% reduction due to the PV array. This study is unique as the impact of tilted and flush PV arrays could be compared against a typical exposed roof at the same roof for a commercial uninhabited building with exposed ceiling and consisting only of the building envelope. Our results indicate a more comfortable indoor environment in PV covered buildings without HVAC both in hotter and cooler seasons.
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- 2010
12. Integration for Airborne Dust Prediction Systems and Vegetation Phenology to Track Pollen for Asthma Alerts in Public Health Decision Support Systems
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Luvall, J. C, Sprigg, W. A, Nickovic, S, Huete, A, Budge, A, and Flowers, L
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Earth Resources And Remote Sensing - Abstract
The objective of the program is to assess the feasibility of combining a dust transport model with MODIS derived phenology to study pollen transport for integration with a public health decision support system. The use of pollen information has specifically be identified as a critical need by the New Mexico State Health department for inclusion in the Environmental Public Health Tracking (EPHT) program. Material and methods: Pollen can be transported great distances. Local observations of plan phenology may be consistent with the timing and source of pollen collected by pollen sampling instruments. The Dust REgional Atmospheric Model (DREAM) is an integrated modeling system designed to accurately describe the dust cycle in the atmosphere. The dust modules of the entire system incorporate the state of the art parameterization of all the major phases of the atmospheric dust life such as production, diffusion, advection, and removal. These modules also include effects of the particles size distribution on aerosol dispersion. The model was modified to use pollen sources instead of dust. Pollen release was estimated based on satellite-derived phenology of key plan species and vegetation communities. The MODIS surface reflectance product (MOD09) provided information on the start of the plant growing season, growth stage, and pollen release. The resulting deterministic model is useful for predicting and simulating pollen emission and downwind concentration to study details of phenology and meteorology and their dependencies. The proposed linkage in this project provided critical information on the location timing and modeled transport of pollen directly to the EPHT> This information is useful to support the centers for disease control and prevention (CDC)'s National EPHT and the state of New Mexico environmental public health decision support for asthma and allergies alerts.
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- 2008
13. Analysis of Upper Air, Ground and Remote Sensing Data For the ATLAS Field Campaign in San Juan, Puerto Rico
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Gonzalez, J. E, Luvall, J. C, Rickman, D, Comarazamy, D. E, and Picon, A
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Earth Resources And Remote Sensing - Abstract
The Atlas San Juan Mission was conducted in February 2004 with the main objectives of observing the Urban Heat Island of San Juan, providing high resolution data of the land use for El Yunque Rain Forest and for calibrating remote sensors. The mission was coordinated with NASA staff members at Marshall, Stennis, Goddard, and Glenn. The Airborne Thermal and Land Applications Sensor (ATLAS) from NASA/Stennis, that operates in the visual and IR bands, was used as the main sensor and was flown over Puerto Rico in a Lear 23 jet plane. To support the data gathering effort by the ATLAS sensor, remote sensing observations and upper air soundings were conducted along with the deployment of a number of ground based weather stations and temperature sensors. This presentation focuses in the analysis of this complementary data for the Atlas San Juan Mission. Upper air data show that during the days of the mission the Caribbean mid and high atmospheres were relatively dry and highly stable reflecting positive surface lifted index, a necessary condition to conduct this suborbital campaign. Surface wind patterns at levels below 850mb were dominated by the easterly trades, while the jet stream at the edge of the troposphere dominated the westerly wind at levels above 500mb. The jet stream remained at high latitudes reducing the possibility of fronts. In consequence, only 8.4 mm of precipitation were reported during the entire mission. Observation of soundings located about 150 km apart reflected minimum variations of the boundary layer across the island for levels below 850 meters and a uniform atmosphere for higher levels. The weather stations and the temperature sensors were placed at strategic locations to observe variations across the urban and rural landscapes. Time series plot of the stations' data show that heavily urbanized commercial areas have higher air temperatures than urban and suburban residential areas, and much higher temperatures than rural areas. Temperature differences [dT(U-R)] were obtained by subtracting the values of several stations from a reference urban station, located in the commercial area of San Juan. These time series show that the UHI peaks during the morning between 10:00am and noon to an average of 4.5 C, a temporal pattern not previously observed in similar studies for continental cities. It is also observed a high variability of the UHI with the precipitation patterns even for short events. These results may be a reflection of a large land use density by low level buildings with an apparent absence of significant heat storage effects in the urban areas, and the importance of the surrounding soil and vegetation moisture in controlling the urban tropical climate. The ATLAS data was used to determine albedo and surface temperature patterns on a 10m scale for the study area. These data were used to calibrate the spatial distribution of the surface temperature when using remote sensing images from MODIS (Moderate Resolution Imaging Spectroradiometer). Surface temperatures were estimated using the land surface temperature product MOD11_L2 distributed by the Land Process Distributed Active Archive Center (LP DAAC). These results show the maximum, minimum and average temperatures in San Juan and in the entire Island at a resolution of 1 km. The information retrieved from MODIS for land surface temperatures reflected similar temporal and spatial variations as the weather stations and ATLAS measurements with a highest absolute offset of about 5 C due to the differences between surface and air temperatures.
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- 2004
14. Mapping Surface Soil Organic Carbon for Crop Fields with Remote Sensing
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Chen, Feng, Kissel, David E, West, Larry T, Rickman, Doug, Luvall, J. C, and Adkins, Wayne
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Earth Resources And Remote Sensing - Abstract
The organic C concentration of surface soil can be used in agricultural fields to vary crop production inputs. Organic C is often highly spatially variable, so that maps of soil organic C can be used to vary crop production inputs using precision farming technology. The objective of this research was to demonstrate the feasibility of mapping soil organic C on three fields, using remotely sensed images of the fields with a bare surface. Enough soil samples covering the range in soil organic C must be taken from each field to develop a satisfactory relationship between soil organic C content and image reflectance values. The number of soil samples analyzed in the three fields varied from 22 to 26. The regression equations differed between fields, but gave highly significant relationships with R2 values of 0.93, 0.95, and 0.89 for the three fields. A comparison of predicted and measured values of soil organic C for an independent set of 2 soil samples taken on one of the fields gave highly satisfactory results, with a comparison equation of % organic C measured + 1.02% organic C predicted, with r2 = 0.87.
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- 2004
15. Mapping Soil pH Buffering Capacity of Selected Fields
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Weaver, A. R, Kissel, D. E, Chen, F, West, L. T, Adkins, W, Rickman, D, and Luvall, J. C
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Inorganic, Organic And Physical Chemistry - Abstract
Soil pH buffering capacity, since it varies spatially within crop production fields, may be used to define sampling zones to assess lime requirement, or for modeling changes in soil pH when acid forming fertilizers or manures are added to a field. Our objective was to develop a procedure to map this soil property. One hundred thirty six soil samples (0 to 15 cm depth) from three Georgia Coastal Plain fields were titrated with calcium hydroxide to characterize differences in pH buffering capacity of the soils. Since the relationship between soil pH and added calcium hydroxide was approximately linear for all samples up to pH 6.5, the slope values of these linear relationships for all soils were regressed on the organic C and clay contents of the 136 soil samples using multiple linear regression. The equation that fit the data best was b (slope of pH vs. lime added) = 0.00029 - 0.00003 * % clay + 0.00135 * % O/C, r(exp 2) = 0.68. This equation was applied within geographic information system (GIS) software to create maps of soil pH buffering capacity for the three fields. When the mapped values of the pH buffering capacity were compared with measured values for a total of 18 locations in the three fields, there was good general agreement. A regression of directly measured pH buffering capacities on mapped pH buffering capacities at the field locations for these samples gave an r(exp 2) of 0.88 with a slope of 1.04 for a group of soils that varied approximately tenfold in their pH buffering capacities.
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- 2003
16. The Design of a Remote Sensing Data Acquisition Campaign for Precision Agriculture and Some Early Results
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Rickmanl, D, Luvall, J. C, Wersinger, J. M, Mask, P, and Kissel, D. E
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Earth Resources And Remote Sensing - Abstract
In the 1970s NASA and the Department of Agriculture attempted to use the new Landsat MSS system for agricultural purposes. The program had relatively little success. With the advent of differential GPS, yield monitors on harvest equipment and higher spatial resolution remote sensing systems it seemed likely the situation should be reexamined. Therefore, a campaign of data acquisition involving remote sensing and other modalities with dependent research was assembled and funded by the Space Grant Consortia in Alabama and Georgia. The design of the remote sensing data acquisition was driven by the biology and physics of the crop system and limited by the available sensor platforms. Major parameters included crop stage, spatial resolution, seasonal and daily weather conditions, and which portion of the EM spectrum would actually capture the most discriminating information. Joint visible and Near IR with Thermal IR would permit use of existing indices, such as greenness, as well as phenomena driven by the plant' s evapotranspiration. Spatial resolution in the 2-5 meter range was chosen, avoiding many complexities caused by aliasing crop row spacing at, higher resolutions yet finer than the harvester's tightest recording rate. This dictates use of an airborne system. Use of an airborne system also makes scheduling around weather much simpler than use of satellite data. Active video calibration was recognized as essential if quantitative measures were ever to be obtained or reproduced. The system would also have to have onboard geoOF1 Based on these elements 3 data acquisitions have been flown. Seven flight lines were flown twice in 1998 and 16 lines flown in 1999. Total raw data is several GBytes. All of the data has now been geometrically corrected and some preliminary analysis accomplished. The thermal bands have an extremely high correlation with yield. For one@test case with corn, correlation in excess of 0.86 was obtained from a data acquisition two months prior to harvest! Soil images show significant within field variation in clay, soil brightness and emissivity. Light wind has been found to effect the reflectance and temperature of broad leaf crops, including soybeans, cotton and peanuts. Clearly, this work has already demonstrated some very important results. With continued development of the remote sensing technology there is good reason to believe this research will soon be able to help the individual farmer.
- Published
- 1999
17. A New Image Processing and GIS Package
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Rickman, D, Luvall, J. C, and Cheng, T
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Geosciences (General) - Abstract
The image processing and GIS package ELAS was developed during the 1980's by NASA. It proved to be a popular, influential and powerful in the manipulation of digital imagery. Before the advent of PC's it was used by hundreds of institutions, mostly schools. It is the unquestioned, direct progenitor or two commercial GIS remote sensing packages, ERDAS and MapX and influenced others, such as PCI. Its power was demonstrated by its use for work far beyond its original purpose, having worked several different types of medical imagery, photomicrographs of rock, images of turtle flippers and numerous other esoteric imagery. Although development largely stopped in the early 1990's the package still offers as much or more power and flexibility than any other roughly comparable package, public or commercial. It is a huge body or code, representing more than a decade of work by full time, professional programmers. The current versions all have several deficiencies compared to current software standards and usage, notably its strictly command line interface. In order to support their research needs the authors are in the process of fundamentally changing ELAS, and in the process greatly increasing its power, utility, and ease of use. The new software is called ELAS II. This paper discusses the design of ELAS II.
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- 1998
18. Application of High-Resolution Thermal Infrared Remote Sensing and GIS to Assess the Urban Heat Island Effect
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Lo, C. P, Quattrochi, D. A, and Luvall, J. C
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Earth Resources And Remote Sensing - Abstract
Day and night airborne thermal infrared image data at 5 m spatial resolution acquired with the 15-channel (0.45 micron - 12.2 micron) Advanced Thermal and Land Applications Sensor (ATLAS) over Alabama, Huntsville on 7 September, 1994 were used to study changes in the thermal signatures of urban land cover types between day and night. Thermal channel number 13 (9.6 micron - 10.2 micron) data with the best noise-equivalent temperature change (NEAT) of 0.25 C after atmospheric corrections and temperature calibration were selected for use in this analysis. This research also examined the relation between land cover irradiance and vegetation amount, using the Normalized Difference Vegetation Index (NDVI), obtained by ratioing the difference and the sum of the red (channel number 3: 0.60-0.63 micron) and reflected infrared (channel number 6: 0.76-0.90 micron) ATLAS data. Based on the mean radiance values, standard deviations, and NDVI extracted from 351 pairs of polygons of day and night channel number 13 images for the city of Huntsville, a spatial model of warming and cooling characteristics of commercial, residential, agricultural, vegetation, and water features was developed using a GIS approach. There is a strong negative correlation between NDVI and irradiance of residential, agricultural, and vacant/transitional land cover types, indicating that the irradiance of a land cover type is greatly influenced by the amount of vegetation present. The predominance of forests, agricultural, and residential uses associated with varying degrees of tree cover showed great contrasts with commercial and services land cover types in the center of the city, and favors the development of urban heat islands. The high-resolution thermal infrared images match the complexity of the urban environment, and are capable of characterizing accurately the urban land cover types for the spatial modeling of the urban heat island effect using a GIS approach.
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- 1997
- Full Text
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19. Geocoding and stereo display of tropical forest multisensor datasets
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Welch, R, Jordan, T. R, and Luvall, J. C
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Earth Resources And Remote Sensing - Abstract
Concern about the future of tropical forests has led to a demand for geocoded multisensor databases that can be used to assess forest structure, deforestation, thermal response, evapotranspiration, and other parameters linked to climate change. In response to studies being conducted at the Braulino Carrillo National Park, Costa Rica, digital satellite and aircraft images recorded by Landsat TM, SPOT HRV, Thermal Infrared Multispectral Scanner, and Calibrated Airborne Multispectral Scanner sensors were placed in register using the Landsat TM image as the reference map. Despite problems caused by relief, multitemporal datasets, and geometric distortions in the aircraft images, registration was accomplished to within + or - 20 m (+ or - 1 data pixel). A digital elevation model constructed from a multisensor Landsat TM/SPOT stereopair proved useful for generating perspective views of the rugged, forested terrain.
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- 1990
20. Application of remote sensing in tropical forests
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Joyce, Armond T, Luvall, J. C, and Sever, T
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Earth Resources And Remote Sensing - Abstract
Cloud cover in tropical humid forests can pose serious operational constraints on Landsat TM and SPOT HRV instrumentation, given their respective orbital frequencies of 16 and 26 days. SAR data intrinsically precludes such problems; the increase of data acquisition frequency to daily rates, as with the NOAA AVHRR instrument, also bears consideration. It is deemed essential that SAR data-related research be expedited, in order to ascertain inherent SAR information for tropical forests in a timely and cost-effective manner.
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- 1990
21. Quantification and mitigation of long-term impacts of urbanization and climate change in the tropical coastal city of San Juan, Puerto Rico
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Comarazamy, D. E., primary, Gonzalez, J. E., additional, and Luvall, J. C., additional
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- 2013
- Full Text
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22. Modeling surface temperature distributions in forest landscapes
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Holbo, H. R and Luvall, J. C
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Earth Resources And Remote Sensing - Abstract
A model of the frequency distributions of the spatial variability in surface temperature is presented. Surface temperature data are obtained from two daytime and two nighttime flights of the Thermal IR Multispectral Scanner (TIMS) over forest land in western Oregon in August, 1985. The temperature values are corrected for atmospheric attenuation and thermal radiation emission with the LOWTRAN-6 algorithm. The temperature distributions were modeled with a two-parameter beta probability density distribution and the fit of the model was evaluated by comparison with the TIMS data set. Use of the model's parameters to identify and classify surface types shows good discrimination among various surfaces for the daytime images, with less distinct discrimination for the nighttime images.
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- 1989
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23. Measurements of short-term thermal responses of coniferous forest canopies using thermal scanner data
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Luvall, J. C and Holbo, H. R
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Earth Resources And Remote Sensing - Abstract
Thermal Infrared Multispectral Scanner (TIMS) data were collected over a coniferous forest in western Oregon. Concurrent radiosonde measurements of atmospheric profiles of air temperature and moisture provided inputs to LOWTRAN6 for atmospheric radiance corrections of the TIMS data. Surface temperature differences measured by the TIMS over time between flight lines were combined with surface radiative energy balance estimates to develop thermal response numbers (TRN). These numbers characterized the thermal response of the diffent surface types. Barren surfaces had the lowest TRN, whereas the forested surfaces had the highest.
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- 1989
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24. Using the thermal infrared multispectral scanner (TIMS) to estimate surface thermal responses
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Luvall, J. C and Holbo, H. R
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Instrumentation And Photography - Abstract
A series of measurements was conducted over the H.J. Andrews, Oregon, experimental coniferous forest, using airborne thermal infrared multispectral scanner (TIMS). Flight lines overlapped, with a 28-min time difference between flight lines. Concurrent radiosonde measurements of atmospheric profiles of air temperature and moisture were used for atmospheric radiance corrections of the TIMS data. Surface temperature differences over time between flight lines were used to develop thermal response numbers (TRNs) which characterized the thermal response (in KJ/sq m/C, where K is the measured incoming solar radiation) of the different surface types. The surface types included a mature forest (canopy dominated by dense crowns of Pseudosuga menziesii, with a secondary canopy of dense Tsuga heterophylla, and also a tall shrub layer of Acer circinatum) and a two-year-old clear-cut. The temperature distribution, within TIMS thermal images was found to reflect the surface type examined. The clear-cut surface had the lowest TRN, while mature Douglas fir the highest.
- Published
- 1987
25. Mapping Soil Organic Carbon Concentration for Multiple Fields with Image Similarity Analysis
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Chen, Feng, primary, Kissel, David E., additional, West, Larry T., additional, Adkins, W., additional, Rickman, Doug, additional, and Luvall, J. C., additional
- Published
- 2008
- Full Text
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26. Mapping Soil pH Buffering Capacity of Selected Fields in the Coastal Plain
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Weaver, A. R., primary, Kissel, D. E., additional, Chen, F., additional, West, L. T., additional, Adkins, W., additional, Rickman, D., additional, and Luvall, J. C., additional
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- 2004
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27. Mapping Soil Organic Carbon Concentration for Multiple Fields with Image Similarity Analysis.
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Feng Chen, Kissel, David E., West, larry T., Adkins, W., Rickman, Doug, and Luvall, J. C.
- Subjects
CARBON ,CARBON in soils ,SOIL management ,SOIL mapping ,SOIL conservation ,SOIL productivity ,SOIL restoration ,SOIL science ,ARTIFICIAL neural networks - Abstract
Remotely sensed imagery with high spatial resolution has been used to map soil organic carbon (SOC) concentrations at a field scale with greatly increased accuracy and reduced cost compared with grid sampling. The procedure, however, requires each crop field to be sampled and mapped separately. The purpose of this study was to determine if cost could be reduced further by grouping a number of crop fields based on their image similarity, and then mapping them together as one group. Ten crop fields with a bare soil surface were selected from a 2000 NASA ATLAS image. The similarity among these fields was examined with the Ward neural network system (WNNS) using the image histogram features extracted from the image for each field. Seven fields were placed into two groups based on the coefficient of determination (R2) values computed from WNNS, with one group consisting of three fields and the second consisting of four fields. Soil samples were taken from the seven fields along with their global positioning system locations and were divided into two data sets, with one for model development and the other for result checking. Models for mapping SOC concentrations were developed for each group of fields using a single procedure. The resulting maps were checked based on soil sample sets that were not used in model development and showed good agreement between mapped values and lab-determined values, with r
2 values of 0.80 for one group of fields and 0.77 for the second group of fields. The models were greatly improved compared with the model developed for all seven fields (R2 was 0.87 and 0.91 for two groups vs. 0.63 for all fields and RMSE was 0.108 and 0.143 vs. 0.219 of SOC percentage). The model developed with similarity grouping was also compared with the model for field-by-field mapping and showed close agreement (R2 was 0.87 for Group 1 vs. 0.89 for Field 2 only in Group 1 and RMSE was 0.108 vs. 0.119 for the same field). [ABSTRACT FROM AUTHOR]- Published
- 2008
- Full Text
- View/download PDF
28. Growth and mineral nutrition of cattails inhabiting a thermally‐graded south carolina reservoir: II. The micronutrients.
- Author
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Adriano, D. C., Sharitz, R. R., Ciravolo, T. G., Luvall, J. C., and Harding, S. A.
- Published
- 1984
- Full Text
- View/download PDF
29. Growth and mineral nutrition of cattails inhabiting a thermally‐graded South Carolina reservoir: I. Growth and the macronutrients.
- Author
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Sharitz, R. R., Adriano, D. C., Pinder, J. E., Luvall, J. C., and Ciravolo, T. G.
- Published
- 1984
- Full Text
- View/download PDF
30. A decision support information system for urban landscape management using thermal infrared data
- Author
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Quattrochi, D. A., Luvall, J. C., Doug Rickman, Estes M G, Jr, Laymon, C. A., and Howell, B. F.
31. Use of MODIS satellite images and an atmospheric dust transport model to evaluate juniperus spp. Pollen phenology and dispersal
- Author
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Luvall, J. C., Sprigg, W. A., Levetin, E., Huete, A., Nickovic, S., Pejanovic, G. A., Ana Vukovic Vimic, Water, P. K., Myers, O. B., Budge, A. M., Zelicoff, A. P., Bunderson, L., and Crimmins, T. M.
32. Mapping surface soil organic carbon for crop fields with remote sensing.
- Author
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Chen, F., Kissel, D. E., West, L. T., Rickman, D., Luvall, J. C., and Adkins, W.
- Subjects
- *
CARBON in soils , *ENVIRONMENTAL mapping , *REMOTE sensing , *GLOBAL Positioning System , *FARMS - Abstract
The soil organic carbon (C) concentration of surface soil can be used in agricultural fields to vary crop production inputs. Soil organic C is often highly spatially variable, so that maps of soil organic carbon can be used to vary crop production inputs using precision farming technology. The objective of this research was to demonstrate the feasibility of mapping soil organic carbon on three fields, using remotely sensed images of the fields with a bare surface. Soil samples covering the range in soil organic carbon were taken from each field to develop a satisfactory relationship between soil organic carbon content and image reflectance values. The regression equations differed between fields, but gave highly significant relationships with R² values of 0.93, 0.95, and 0.89 for the three fields. Two classification, arbitrarily classification and a minimum distance clustering, were applied in mapping soil organic carbon. A comparison of mapped soil organic carbon with an independent set of 21 soil samples taken on one of the fields gave highly satisfactory results for the two methods with r² = 0.81 and 0.87. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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