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Full-Text Articles in Engineering
Sharpening Ecostress And Viirs Land Surface Temperature Using Harmonized Landsat-Sentinel Surface Reflectances, Jie Xue, Martha C. Anderson, Feng Gao, Christopher Hain, Liang Sun, Yun Yang, Kyle R. Knipper, William P. Kustas, Alfonso F. Torres-Rua, Mitch Schull
Sharpening Ecostress And Viirs Land Surface Temperature Using Harmonized Landsat-Sentinel Surface Reflectances, Jie Xue, Martha C. Anderson, Feng Gao, Christopher Hain, Liang Sun, Yun Yang, Kyle R. Knipper, William P. Kustas, Alfonso F. Torres-Rua, Mitch Schull
Civil and Environmental Engineering Faculty Publications
Land surface temperature (LST) is a key diagnostic indicator of agricultural water use and crop stress. LST data retrieved from thermal infrared (TIR) band imagery, however, tend to have a coarser spatial resolution (e.g., 100 m for Landsat 8) than surface reflectance (SR) data collected from shortwave bands on the same instrument (e.g., 30 m for Landsat). Spatial sharpening of LST data using the higher resolution multi-band SR data provides an important path for improved agricultural monitoring at sub-field scales. A previously developed Data Mining Sharpener (DMS) approach has shown great potential in the sharpening of Landsat LST using Landsat …
Implications Of Soil And Canopy Temperature Uncertainty In The Estimation Of Surface Energy Fluxes Using Tseb2t And High-Resolution Imagery In Commercial Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian
Implications Of Soil And Canopy Temperature Uncertainty In The Estimation Of Surface Energy Fluxes Using Tseb2t And High-Resolution Imagery In Commercial Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian
Civil and Environmental Engineering Faculty Publications
Estimation of surface energy fluxes using thermal remote sensing–based energy balance models (e.g., TSEB2T) involves the use of local micrometeorological input data of air temperature, wind speed, and incoming solar radiation, as well as vegetation cover and accurate land surface temperature (LST). The physically based Two-source Energy Balance with a Dual Temperature (TSEB2T) model separates soil and canopy temperature (Ts and Tc) to estimate surface energy fluxes including Rn, H, LE, and G. The estimation of Ts and Tc components for the TSEB2T model relies on the linear relationship between the composite land surface temperature and a vegetation index, namely …
To What Extent Does The Eddy Covariance Footprint Cutoff Influence The Estimation Of Surface Energy Fluxes Using Two Source Energy Balance Model And High-Resolution Imagery In Commercial Vineyards?, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Louis Sanchez, Nick Dokoozlian
To What Extent Does The Eddy Covariance Footprint Cutoff Influence The Estimation Of Surface Energy Fluxes Using Two Source Energy Balance Model And High-Resolution Imagery In Commercial Vineyards?, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Héctor Nieto, Mac Mckee, Lawrence Hipps, Joseph Alfieri, John H. Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Louis Sanchez, Nick Dokoozlian
Civil and Environmental Engineering Faculty Publications
Validation of surface energy fluxes from remote sensing sources is performed using instantaneous field measurements obtained from eddy covariance (EC) instrumentation. An eddy covariance measurement is characterized by a footprint function / weighted area function that describes the mathematical relationship between the spatial distribution of surface flux sources and their corresponding magnitude. The orientation and size of each flux footprint / source area depends on the micro-meteorological conditions at the site as measured by the EC towers, including turbulence fluxes, friction velocity (ustar), and wind speed, all of which influence the dimensions and orientation of the footprint. The …
Influence Of Model Grid Size On The Estimation Of Surface Fluxes Using The Two Source Energy Balance Model And Suas Imagery In Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Hector Nieto, Mac Mckee, Lawrence E. Hipps, David King Stevens, Joseph Alfieri, John Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian
Influence Of Model Grid Size On The Estimation Of Surface Fluxes Using The Two Source Energy Balance Model And Suas Imagery In Vineyards, Ayman Nassar, Alfonso F. Torres-Rua, William Kustas, Hector Nieto, Mac Mckee, Lawrence E. Hipps, David King Stevens, Joseph Alfieri, John Prueger, Maria Mar Alsina, Lynn Mckee, Calvin Coopmans, Luis Sanchez, Nick Dokoozlian
Civil and Environmental Engineering Faculty Publications
Evapotranspiration (ET) is a key variable for hydrology and irrigation water management,with significant importance in drought-stricken regions of the western US. This is particularly true for California, which grows much of the high-value perennial crops in the US. The advent of small Unmanned Aerial System (sUAS) with sensor technology similar to satellite platforms allows for the estimation of high-resolution ET at plant spacing scale for individual fields. However, while multiple efforts have been made to estimate ET from sUAS products, the sensitivity of ET models to different model grid size/resolution in complex canopies, such as vineyards, is still unknown.The variability …
Assessment Of Groundwater Resources In Siwa Oasis, Western Desert, Egypt, Noha H. Moghazy, Jagath J. Kaluarachchi
Assessment Of Groundwater Resources In Siwa Oasis, Western Desert, Egypt, Noha H. Moghazy, Jagath J. Kaluarachchi
Civil and Environmental Engineering Faculty Publications
One of the major challenges facing Egypt is limited water resources associated with rapid increase in population. In 1960s, Egyptian government started to use groundwater from the Nubian Sandstone Aquifer System (NSAS) in the Western Desert to expand agricultural sector. Siwa Oasis is the focus of this study to assess the efficiency of groundwater use and corresponding impacts from 1980 to 2012. Results show that from 1980 to 1998, withdrawal from poorly designed wells increased rapidly causing an increase in excess water about 336%. The increase of excess water with the usage of poor drainage produced lakes. Remote Sensing showed …
Spatial And Temporal Analysis Of Precipitation And Effective Rainfall Using Gauge Observations, Satellite, And Gridded Climate Data For Agricultural Water Management In The Upper Colorado River Basin, Mahyar Aboutalebi, Alfonso F. Torres-Rua, L. Niel Allen
Spatial And Temporal Analysis Of Precipitation And Effective Rainfall Using Gauge Observations, Satellite, And Gridded Climate Data For Agricultural Water Management In The Upper Colorado River Basin, Mahyar Aboutalebi, Alfonso F. Torres-Rua, L. Niel Allen
Civil and Environmental Engineering Faculty Publications
Accurate spatial and temporal precipitation estimates are important for hydrological studies of irrigation depletion, net irrigation requirement, natural recharge, and hydrological water balances in defined areas. This analysis supports the verification of water savings (reduced depletion)from deficit irrigation of pastures in the Upper Colorado River Basin. The study area has diverse topography with scattered fields and few precipitation gauges that are not representative of the basin.Gridded precipitation products from TRMM-3B42, PRISM, Daymet, and gauge observations were evaluated on two case studies located in Colorado and Wyoming during the 2014–2016 irrigation seasons. First, the resolution at the farm level is discussed. …
Estimation Of Surface Soil Moisture In Irrigated Lands By Assimilation Of Landsat Vegetation Indices, Surface Energy Balance Products, And Relevance Vector Machines, Alfonso F. Torres-Rua, Andres M. Ticlavilca, Roula Bachour, Mac Mckee
Estimation Of Surface Soil Moisture In Irrigated Lands By Assimilation Of Landsat Vegetation Indices, Surface Energy Balance Products, And Relevance Vector Machines, Alfonso F. Torres-Rua, Andres M. Ticlavilca, Roula Bachour, Mac Mckee
Civil and Environmental Engineering Faculty Publications
Spatial surface soil moisture can be an important indicator of crop conditions on farmland, but its continuous estimation remains challenging due to coarse spatial and temporal resolution of existing remotely-sensed products. Furthermore, while preceding research on soil moisture using remote sensing (surface energy balance, weather parameters, and vegetation indices) has demonstrated a relationship between these factors and soil moisture, practical continuous spatial quantification of the latter is still unavailable for use in water and agricultural management. In this study, a methodology is presented to estimate volumetric surface soil moisture by statistical selection from potential predictors that include vegetation indices and …
Estimating Chlorophyll With Thermal And Broadband Multispectral High Resolution Imagery From An Unmanned Aerial System Using Relevance Vector Machines For Precision Agriculture, Manal Elarab, Andres M. Ticlavilca, Alfonso F. Torres-Rua, Inga Maslova, Mac Mckee
Estimating Chlorophyll With Thermal And Broadband Multispectral High Resolution Imagery From An Unmanned Aerial System Using Relevance Vector Machines For Precision Agriculture, Manal Elarab, Andres M. Ticlavilca, Alfonso F. Torres-Rua, Inga Maslova, Mac Mckee
Civil and Environmental Engineering Faculty Publications
Precision agriculture requires high-resolution information to enable greater precision in the management of inputs to production. Actionable information about crop and field status must be acquired at high spatial resolution and at a temporal frequency appropriate for timely responses. In this study, high spatial resolution imagery was obtained through the use of a small, unmanned aerial system called AggieAirTM. Simultaneously with the AggieAir flights, intensive ground sampling for plant chlorophyll was conducted at precisely determined locations. This study reports the application of a relevance vector machine coupled with cross validation and backward elimination to a dataset composed of reflectance from …
Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso F. Torres-Rua, Austin M. Jensen, Mac Mckee
Assessment Of Surface Soil Moisture Using High-Resolution Multi-Spectral Imagery And Artificial Neural Networks, Leila Hassan-Esfahani, Alfonso F. Torres-Rua, Austin M. Jensen, Mac Mckee
Civil and Environmental Engineering Faculty Publications
Many crop production management decisions can be informed using data from high-resolution aerial images that provide information about crop health as influenced by soil fertility and moisture. Surface soil moisture is a key component of soil water balance, which addresses water and energy exchanges at the surface/atmosphere interface; however, high-resolution remotely sensed data is rarely used to acquire soil moisture values. In this study, an artificial neural network (ANN) model was developed to quantify the effectiveness of using spectral images to estimate surface soil moisture. The model produces acceptable estimations of surface soil moisture (root mean square error (RMSE) = …
Estimation Of Dariy Particulate Matter Emission Rates By Lidar And Inverse Modeling, C. C. Marchant, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, R L. Pfeiffer, K H. Prueger, J L. Hatfield
Estimation Of Dariy Particulate Matter Emission Rates By Lidar And Inverse Modeling, C. C. Marchant, Kori D. Moore, Michael D. Wojcik, Randy S. Martin, R L. Pfeiffer, K H. Prueger, J L. Hatfield
Civil and Environmental Engineering Faculty Publications
Particulate matter (PM) emissions from agricultural operations are an important issue for air quality and human health and a topic of interest to government regulators. PM emission rates from a dairy in the San Joaquin Valley of California were investigated during June 2008. The facility had 1,885 total animals, including 950 milking cows housed in free-stall pens with an open-lot exercise area, and 935 dry cows, steers, bulls, and heifers housed in open lots. Point sensors, including filter-based aerodynamic mass samplers and optical particle counters (OPC), were deployed at select points around the facility to measure optical and aerodynamic particulate …
Integration Of Remote Lidar And In-Situ Measured Data To Estimate Particulate Flux And Emission From Tillage Operations, Vladmir V. Zavyalov, Gail E. Bingham, Michael D. Wojcik, Jerry L. Hatfield, Thomas D. Wilkerson, Randy S. Martin, Christian Marchant, Kori D. Moore, Bill Bradford
Integration Of Remote Lidar And In-Situ Measured Data To Estimate Particulate Flux And Emission From Tillage Operations, Vladmir V. Zavyalov, Gail E. Bingham, Michael D. Wojcik, Jerry L. Hatfield, Thomas D. Wilkerson, Randy S. Martin, Christian Marchant, Kori D. Moore, Bill Bradford
Civil and Environmental Engineering Faculty Publications
Agriculture, through wind erosion, tillage and harvest operations, burning, diesel-powered machinery and animal production operations, is a source of particulate matter emissions. Agricultural sources vary both temporally and spatially due to daily and seasonal activities and inhomogeneous area sources. Conventional point sampling methods originally designed for regional, well mixed aerosols are challenged by the disrupted wind flow and by the small mobile source of the emission encountered in this study. Atmospheric lidar (LIght Detection And Ranging) technology provides a means to derive quantitative information of particulate spatial and temporal distribution. In situ point measurements of particulate physical and chemical properties …
Strategies For Lidar Characterization Of Particulates From Point And Area Sources, Michael D. Wojcik, Kori D. Moore, Randy S. Martin, Jerry Hatfield
Strategies For Lidar Characterization Of Particulates From Point And Area Sources, Michael D. Wojcik, Kori D. Moore, Randy S. Martin, Jerry Hatfield
Civil and Environmental Engineering Faculty Publications
Use of ground based remote sensing technologies such as scanning lidar systems (light detection and ranging) has gained traction in characterizing ambient aerosols due to some key advantages such as wide area of regard (10 km2 ), fast response time, high spatial resolution (m) and high sensitivity. Energy Dynamics Laboratory and Utah State University, in conjunction with the USDA-ARS, has developed a three-wavelength scanning lidar system called Aglite that has been successfully deployed to characterize particle motion, concentration, and size distribution at both point and diffuse area sources in agricultural and industrial settings. A suite of massbased and size distribution …