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Aaron T Freeman

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This study uses growth in vegetation during the monsoon season measured from LANDSAT imagery as a proxy for measured rainfall. NDVI values from 26 years of pre- and post-monsoon season Landsat imagery were derived across Yuma Proving Ground (YPG) in southwestern Arizona, USA. The LANDSAT imagery (1986-2011) was downloaded from USGS’s GlobeVis website (http://glovis.usgs.gov/). Change in NDVI was calculated within a set of 2,843 Riparian Area Polygons (RAPs) up to 1 km in length defined in ESRI ArcMap 10.2.
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Gas field infrastructure elements contributing to land disturbance located in four gas fields (Continental Divide – Creston – Blue Gap (CCB), Jonah, Moxa Arch, and Pinedale Anticline Project Area) in southwestern Wyoming were collected as polygon features in ArcGIS. Classes included four types of roads, well pads (active and abandoned), residual disturbance associated with the well pads, buried utilities, disturbances associated with non-well pad industry facilities, and areas of general disturbance associated with the installation and operation of gas wells not fitting one of the other disturbance class definitions.
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Analysis of Land Disturbance and Pygmy Rabbit Occupancy Values Associated With Oil and Gas Extraction in Southwestern Wyoming, 2012
Pygmy rabbits (Brachylagus idahoensis) are a Species of Greatest Conservation Need in Wyoming. They are designated as such because they are sagebrush obligates and entrained in the health and intactness of sagebrush steppe landscapes. Southwest Wyoming, where pygmy rabbits occur, has become an epicenter of domestic oil and gas exploration and this activity contributes to loss and fragmentation of sagebrush habitats. This tabular file that was used for analysis contains the following data/information: survey site, plot, and gas field; pygmy rabbit occupancy status; UTM coordinates associated with occupancy (dithered to protect pygmy rabbits from further disturbance); an index value indicating amount of fresh pygmy...
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Pygmy rabbits (Brachylagus idahoensis) are a Species of Greatest Conservation Need in Wyoming. They are designated as such because they are sagebrush obligates and entrained in the health and intactness of sagebrush steppe landscapes. Southwest Wyoming, where pygmy rabbits occur, has become an epicenter of domestic oil and gas exploration and this activity contributes to loss and fragmentation of sagebrush habitats. This tabular file that was used for analysis contains the following data/information: survey site, plot, and gas field; pygmy rabbit occupancy status; UTM coordinates associated with occupancy (dithered to protect pygmy rabbits from further disturbance); an index value indicating amount of fresh pygmy...
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The U.S. Geological Survey (USGS) Fort Collins Science Center created a national data set of the footprint area of solar arrays for the Bureau of Land Management’s National Operations Center. We identified potential solar facility locations for the conterminous U.S. using the U.S. Energy Information Administration (EIA) utility-scale facilities data from 2015. The footprint area of each solar array was digitized on-screen using true color aerial imagery from the most recently available National Agriculture Imagery Program (NAIP) for each state (NAIP 2013-2015). We used supplementary ESRI basemap imagery accessed via ArcGIS to verify locations of arrays observed in NAIP imagery. Arrays separated by more than 30 meters...
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