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Utilizing Collocated Crop Growth Model Simulations To Train Agronomic Satellite Retrieval Algorithms, Nathaniel Levitan, Barry Gross
Utilizing Collocated Crop Growth Model Simulations To Train Agronomic Satellite Retrieval Algorithms, Nathaniel Levitan, Barry Gross
Publications and Research
Due to its worldwide coverage and high revisit time, satellite-based remote sensing provides the ability to monitor in-season crop state variables and yields globally. In this study, we presented a novel approach to training agronomic satellite retrieval algorithms by utilizing collocated crop growth model simulations and solar-reflective satellite measurements. Specifically, we showed that bidirectional long short-term memory networks (BLSTMs) can be trained to predict the in-season state variables and yields of Agricultural Production Systems sIMulator (APSIM) maize crop growth model simulations from collocated Moderate Resolution Imaging Spectroradiometer (MODIS) 500-m satellite measurements over the United States Corn Belt at a regional …
Satellite Remote Sensing Of Woody And Herbaceous Leaf Area For Improved Understanding Of Forage Resources And Fire In Africa, Milkah Njoki Kahiu
Satellite Remote Sensing Of Woody And Herbaceous Leaf Area For Improved Understanding Of Forage Resources And Fire In Africa, Milkah Njoki Kahiu
Electronic Theses and Dissertations
In sub-Saharan Africa (SSA) tree-grass systems commonly referred to as savannas dominating drylands, play a critical role in social, cultural, economic and environmental systems. These coupled natural-human systems support millions of people through pastoralism, are important global biodiversity hotspots and play a critical role in global biogeochemical cycles. Despite the importance of SSA savannas, they have been marginalized for years as most governments neglect dryland resources in favor of agricultural research and development assistance. Hence, lack of spatially and temporally accurate information on the status and trends in savanna resources has led to poor planning and management. This scenario calls …
Cross-Scale Correlation Between In Situ Measurements Of Canopy Gap Fraction And Landsat-Derived Vegetation Indices With Implications For Monitoring The Seasonal Phenology In Tropical Forests Using Modis Data, Nicholas Cuba, John Rogan, Deborah Lawrence, Christopher A. Williams
Cross-Scale Correlation Between In Situ Measurements Of Canopy Gap Fraction And Landsat-Derived Vegetation Indices With Implications For Monitoring The Seasonal Phenology In Tropical Forests Using Modis Data, Nicholas Cuba, John Rogan, Deborah Lawrence, Christopher A. Williams
Geography
Deciduousness in dry tropical forests results in substantial seasonal changes to canopy gap fractions. The characterization of such structural properties over large areas is necessary for understanding energy and nutrient distribution within forest ecosystems. However, a spatial extrapolation of measurements from relatively few, spatially-concentrated field observations can yield estimated values that have questionable accuracy and precision at regional scales. This paper uses linear regression models to compare measurements of canopy gap fraction from in situ digital cover photography in the dry tropical forest of the Southern Yucatán, Mexico, to measurements of seasonal vegetation change based on three vegetation indices-the Normalized …
Biomass Burning In The Conterminous United States: A Comparison And Fusion Of Active Fire Observations From Polar-Orbiting And Geostationary Satellites For Emissions Estimation, Fangjun Li
Electronic Theses and Dissertations
Biomass burning is an important source of atmospheric greenhouse gases and aerosol emissions that significantly influence climate and air quality. Estimation of biomassburning emissions (BBE) has been limited to the conventional method in which parameters (i.e., burned area and fuel load) can be challenging to quantify accurately. Recent studies have demonstrated that the rate of biomass combustion is a linear function of fire radiative power (FRP), the instantaneous radiative energy released from actively burning fires, which provides a novel pathway to estimate BBE. To obtain accurate and timely BBE estimates for near real-time applications (i.e., air quality forecast), the satellite …