5,993 research outputs found

    Water-Level and Storage Changes in the High Plains Aquifer, Predevelopment to 2011 and 2009–11

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    The High Plains aquifer underlies 111.8 million acres (175,000 square miles) in parts of eight States—Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial irrigation with groundwater in the aquifer area. This report presents water-level changes in the High Plains aquifer from the time before substantial groundwater irrigation development began (generally before 1950, and termed “predevelopment” in this report) to 2011 and from 2009–11. The report also presents total water in storage, 2011, and change in water in storage in the aquifer from predevelopment to 2011. The methods to calculate area-weighted, average water-level changes; change in water in storage; and total water in storage for this report used geospatial data layers organized as rasters with a cell size of about 62 acres. These methods were modified from methods used in previous reports in an attempt to improve estimates of water-level changes and change in water in storage. Water-level changes from predevelopment to 2011, by well, ranged from a rise of 85 feet to a decline of 242 feet. The area-weighted, average water-level changes in the aquifer were an overall decline of 14.2 feet from predevelopment to 2011, and a decline of 0.1 foot from 2009–11. Total water in storage in the aquifer in 2011 was about 2.96 billion acre-feet, which was a decline of about 246 million acre-feet since predevelopment

    Water-Level and Storage Changes in the High Plains Aquifer, Predevelopment to 2011 and 2009–11

    Get PDF
    The High Plains aquifer underlies 111.8 million acres (175,000 square miles) in parts of eight States—Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Water-level declines began in parts of the High Plains aquifer soon after the beginning of substantial irrigation with groundwater in the aquifer area. This report presents water-level changes in the High Plains aquifer from the time before substantial groundwater irrigation development began (generally before 1950, and termed “predevelopment” in this report) to 2011 and from 2009–11. The report also presents total water in storage, 2011, and change in water in storage in the aquifer from predevelopment to 2011. The methods to calculate area-weighted, average water-level changes; change in water in storage; and total water in storage for this report used geospatial data layers organized as rasters with a cell size of about 62 acres. These methods were modified from methods used in previous reports in an attempt to improve estimates of water-level changes and change in water in storage. Water-level changes from predevelopment to 2011, by well, ranged from a rise of 85 feet to a decline of 242 feet. The area-weighted, average water-level changes in the aquifer were an overall decline of 14.2 feet from predevelopment to 2011, and a decline of 0.1 foot from 2009–11. Total water in storage in the aquifer in 2011 was about 2.96 billion acre-feet, which was a decline of about 246 million acre-feet since predevelopment

    “Gaps” in Intelligence Communications

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    Information is particularly crucial within the military, where the results of miscommunication can be devastating. This master thesis explores the flow of information within the United States Air Force. The author is an intelligence operations officer and he relates his experiences, detailing many of the difficulties that exist in relaying information, and how these difficulties are dealt with. Difficulties explored within this thesis include the heavy use of acronyms and jargon within the military that can be confusing, especially to new recruits and people with no prior military training, as well as working with different commanders, or detailing information outside of the author’s own area of expertise. As a result, preparation for a briefing is widely dependent upon the composition of the audience. The thesis includes four sample modules to illustrate the differences between a situation briefing before and after revisions are made to make accommodations according to the target audience

    Two classes of solar energetic particle events associated with impulsive and long duration soft X-ray flares

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    Solar energetic particle events observed in space have different properties depending on the class of associated flare. Impulsive flares, which occur low in the corona in regions of high energy density, are associated with particle events which are deficient in protons. These events are rarely associated with coronal mass ejections and interplanetary shocks. The vast majority of large, high energy proton events are associated with long duration flares, many of which are also associated with fast coronal mass ejections and strong interplanetary shocks. Such flare events originate relatively high in the corona

    Variations in elemental composition of several MEV/nucleon ions observed in interplanetary space

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    Six years of accumulated ISEE-3 and IMP-8 data to study variations in elemental relative abundances among the different populations of energetic ions seen in interplanetary space are surveyed. Evidence suggesting that heavy ion enrichments may be organized by a rigidity scaling factor A/Z over the range H to Fe is presented. Data to support the hypothesis that shock-associated particles are probably accelerated from ambient energetic fluxes are shown

    Physical properties of Ce3-xTe4 below room temperature

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    The physical properties of polycrystalline Ce3-xTe4 were investigated by measurements of the thermoelectric properties, Hall coefficient, heat capacity, and magnetization. The fully-filled, metallic x=0 compound displays a soft ferromagnetic transition near 4K, and analysis of the corresponding heat capacity anomaly suggests a doublet ground state for Ce^{3+}. The transition is suppressed to below 2K in the insulating x=0.33 composition, revealing that magnetic order in Ce3-xTe4 is driven by an RKKY-type interaction. The thermoelectric properties trend with composition as expected from simple electron counting, and the transport properties in Ce3Te4 are observed to be similar to those in La3Te4. Trends in the low temperature thermal conductivity data reveal that the phonons are efficiently scattered by electrons, while all compositions examined have a lattice thermal conductivity near 1.2W/m/K at 200K.Comment: Submitted to Phys. Rev.

    Evaluation of small area crop estimation techniques using LANDSAT- and ground-derived data

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    Studies completed in fiscal year 1981 in support of the clustering/classification and preprocessing activities of the Domestic Crops and Land Cover project. The theme throughout the study was the improvement of subanalysis district (usually county level) crop hectarage estimates, as reflected in the following three objectives: (1) to evaluate the current U.S. Department of Agriculture Statistical Reporting Service regression approach to crop area estimation as applied to the problem of obtaining subanalysis district estimates; (2) to develop and test alternative approaches to subanalysis district estimation; and (3) to develop and test preprocessing techniques for use in improving subanalysis district estimates
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