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Temporal and spatial sources of silica for chert remain poorly constrained. Modern sources to the worlds oceans include silica in rivers > aeolian (dust) deposition > sea floor vents and submarine weathering. However, changes in aridity and dust flux during the Phanerozoic may explain variations in the ocean silica cycle and times and places of chert formation. The chemistry of fine quartz dust (FQD) provides a chemical mechanism for the transformation of FQD to polymorphs of silica in chert; FQD is readily dissolved, then reprecipitated as Opal-A by either biotic or abiotic processes. An unequivocal relation between increases in dust flux and biogenic opal-A in the western Pacific Ocean during the past 200 kyr...
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This dataset contains the Digital Elevation Model (DEM) for Africa from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database. The DEM data were developed and distributed by processing units. There are 19 processing units for Africa. The distribution files have the number of the processing unit appended to the end of the zip file name (e.g. af_dem_3_2.zip contains the DEM data for unit 3-2). The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment...
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The data document the results of several microbe bioassays performed by the USGS on Phragmites australis plants, including those performed on mature leaves, seedlings, and dead leaf tissues exploration of the literature to find accounts of microbes associated with Phragmites worldwide. For the bioassays, we prepared 162 pure cultures isolated from Phragmites plants in North America along the east coast, Florida, the Gulf of Mexico, and the Great Lakes area, 125 of which were from a previous study, and 38 represent new collections. The DNA sequences used to identify the 37 new collections are included. Microbes were isolated from plants collected from 2015-2018. We performed assays using both North American plant...
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Inland fishes provide important ecosystem services to communities worldwide and are especially vulnerable to the impacts of climate change. Fish respond to climate change in diverse and nuanced ways which creates challenges for practitioners of fish conservation, climate change adaptation, and management. Although climate change is known to affect fish globally, a comprehensive online, public database of how climate change has impacted inland fishes worldwide and adaptation or management practices that may address these impacts does not exist. We conducted an extensive, systematic primary literature review to identify peer-reviewed journal publications describing projected and documented examples of climate change...
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This dataset contains the African continent from the Hydrological Derivatives for Modeling and Analysis (HDMA) database. The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries. The coverage of the data is global (-180º, 180º, -90º, 90º) with the underlying DEM being a hybrid of three datasets: HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales), Global Multi-resolution Terrain Elevation Data 2010 (GMTED2010)...
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This data set contains the Compound Topographic Index (CTI) for Africa from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database. The CTI data were developed and distributed by processing units. There are 19 processing units for Africa. The distribution files have the number of the processing unit appended to the end of the zip file name (e.g. af_cti_3_2.zip contains the CTI data for unit 3-2). The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment...
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This dataset contains the slope for Africa from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database. The slope data were developed and distributed by processing units. There are 19 processing units for Africa. The distribution files have the number of the processing unit appended to the end of the zip file name (e.g. af_slope_3_2.zip contains the slope data for unit 3-2).The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries. The coverage...
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This is the first of two datasets containing derived data necessary to reproduce the results of the associated journal article: "On the Sensitivity of Annual Streamflow to Air Temperature." This first dataset contains basic basin characteristics of 2,673 gaged basins worldwide, along with associated monthly time series of basin-mean precipitation, air temperature, and net radiation. The streamflow data themselves are available directly from the Global Runoff Data Centre. From the inventory of discharge data holdings of the Global Runoff Data Centre, 2,673 stream gages were selected for which (1) at least 25 complete calendar years of monthly data overlapped in time with available climate data; (2) 500-m-resolution...
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This dataset contains the streams derived from the Digital Elevation Model (DEM) for the African continent from the Hydrological Derivatives for Modeling and Analysis (HDMA) database. The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries. The coverage of the data is global (-180º, 180º, -90º, 90º) with the underlying DEM being a hybrid of three datasets: HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales),...
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This dataset contains the Flow Direction (FD) for Africa from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database. The FD data were developed and distributed by processing units. There are 19 processing units for Africa. The distribution files have the number of the processing unit appended to the end of the zip file name (e.g. af_fd_3_2.zip contains the FD data for unit 3-2).The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries. The...
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This dataset contains the Flow Accumulation (FA) for Africa from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database. The FA data were developed and distributed by processing units. There are 19 processing units for Africa. The distribution files have the number of the processing unit appended to the end of the zip file name (e.g. af_fa_3_2.zip contains the FA data for unit 3-2). The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries....
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Honey bees (Apis mellifera), a critical agricultural pollinator in many areas, have a high rate of infection with a large DNA virus, Apis mellifera filamentous virus (AmFV), yet little is known about its ecology or impact on honey bee colonies, other than its ubiquity and apparent low virulence. This study scanned over 5,000 public data sets to detect AmFV sequences in honey bees as well as a parasitic mite of honey bees, Varroa destructor, that is a potential vector of AmFV. The data release consists of these files: 1. AmFV.genome.assemblies.aligned.fas, which contains new AmFV draft genome sequences generated by this study aligned with existing reference genome accessions downloaded from the National Center for...
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SPECPRsplib07 This compressed archive includes: Files, in SPECPR format, containing spectral data and associated metadata descriptions: measured spectra (splib07a) spectra interpolated to a higher number of more finely-spaced channels (splib07b) spectra convolved to other spectrometers, for example Analytical Spectral Devices standard resolution (s07_ASD) AVIRIS-Classic 2014 characteristics (s07_AV14) Hyperspectral Mapper (HyMap) 2014 characteristics (s07_HY14) and others spectra resampled to multispectral sensors: ASTER Landsat 8 OLI Sentinel-2 MSI Worldview-3 Folders containing information linked to from the metadata descriptions in the SPECPR files: README: contains a HTML version of the USGS Data...
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GIFplots Files containing GIF images of spectral plots: GIFplots_splib07a.zip contains plots of measured spectra, including plots showing the full wavelength range of the measured spectra, organized in chapter sub-folders as described previously for the ASCII data. plots showing specific portions of the electromagnetic spectrum are organized folders within the “plots_by_wavelength_region” folder, including: range1_uv_to_visible (0.2 - 1.0 microns) range2_visible_to_swir (0.2 - 2.5 microns) range3_swir (1.5 - 5.5 microns) range4_swir_to_mir (2.5 - 25 microns) range5_swir_to_fir_wavenumber (4,000 - 50 cm-1 which spans 2.5 - 200 microns) plots of spectra interpolated to a higher number of more finely-spaced...
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ASCIIdata Files containing spectral data in ASCII text format: measured spectra (ASCIIdata_splib07a.zip), including wavelength positions and bandpass (Full-Width at Half-Maximum; FWHM) values of channels in the spectrometers utilized spectra interpolated to a higher number of more finely-spaced channels (ASCIIdata_splib07b.zip) spectra convolved to other spectrometers, including the wavelength positions and bandpass (FWHM) values of the channels in the spectrometers, for example Analytical Spectral Devices standard resolution (ASCIIdata_splib07b_cvASD.zip) AVIRIS-Classic 2014 characteristics (ASCIIdata_splib07b_cvAVIRISc2014.zip) Hyperspectral Mapper 2014 characteristics (ASCIIdata_splib07b_cvHYMAP2014.zip) and...
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HTMLmetadata Text files in HTML-format containing metadata about samples and spectra. Also included in the zip file are folders containing information linked to from the HTML files, including: README: contains a HTML version of the USGS Data Series publication, linked to this data release, that describes this spectral library (Kokaly and others, 2017). The folder also contains an HTML version of the release notes. photo_images: contains full resolution images of photos of samples and field sites. photo_thumbs: contains low-resolution thumbnail versions of photos of samples and field sites. GENERAL LIBRARY DESCRIPTION This data release provides the U.S. Geological Survey (USGS) Spectral Library Version 7 and...
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This data release provides the U.S. Geological Survey (USGS) Spectral Library Version 7 and all related documents. The library contains spectra measured with laboratory, field, and airborne spectrometers. The instruments used cover wavelengths from the ultraviolet to the far infrared (0.2 to 200 microns). Laboratory samples of specific minerals, plants, chemical compounds, and man-made materials were measured. In many cases, samples were purified, so that unique spectral features of a material can be related to its chemical structure. These spectro-chemical links are important for interpreting remotely sensed data collected in the field or from an aircraft or spacecraft. This library also contains physically-constructed...
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This dataset contains the catchments derived from the Digital Elevation Model (DEM) for the African continent from the Hydrological Derivatives for Modeling and Analysis (HDMA) database. The HDMA database provides comprehensive and consistent global coverage of raster and vector topographically derived layers, including raster layers of digital elevation model (DEM) data, flow direction, flow accumulation, slope, and compound topographic index (CTI); and vector layers of streams and catchment boundaries. The coverage of the data is global (-180º, 180º, -90º, 90º) with the underlying DEM being a hybrid of three datasets: HydroSHEDS (Hydrological data and maps based on SHuttle Elevation Derivatives at multiple Scales),...
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This is the second of two datasets containing derived data necessary to reproduce the results of the associated journal article: "On the Sensitivity of Annual Streamflow to Air Temperature," intended for publication in Water Resources Research. The first dataset contains monthly time series of basin-mean precipitation, air temperature, and net radiation, along with basin characteristics. This second dataset, using the first as input, contains empirical and theoretical estimates of annual streamflow sensitivities to precipitation, temperature, and previous-year streamflow. For each basin, a water year was defined by optimization of a streamflow regression against precipitation, temperature, and previous-year streamflow;...
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The Global Geochemical Database for Critical Metals in Black Shales (CMIBS) contains new geochemical data compilations for fine-grained sedimentary rocks in which each geologic material sample has one 'best value' determination for each analyzed species, greatly improving speed and efficiency of use (Granitto and others, 2013). The CMIBS was created and designed to compile and integrate geochemical data from seven continents in order to facilitate petrologic studies, mineral resource assessments and mineral exploration, definition of geochemical baseline values and statistics, environmental impact assessments, paleobiological studies and paleoenvironmental trends through Earth history. and studies in human health...


map background search result map search result map Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Compound Topographic Index (CTI) from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Digital Elevation Model (DEM) from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Flow Accumulation (FA) from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Flow direction from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Slope from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Catchments layers from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Streams layers from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Global Geochemical Database for Critical Metals in Black Shales The chemistry of eolian quartz dust and the origin of chert The effects of North American fungi and bacteria on Phragmites australis leaves 2017-2019, with comparisons to the global Phragmites microbiome Streams layers from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Compound Topographic Index (CTI) from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Digital Elevation Model (DEM) from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Flow Accumulation (FA) from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Flow direction from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Slope from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa Catchments layers from the Hydrologic Derivatives for Modeling and Analysis (HDMA) database -- Africa The effects of North American fungi and bacteria on Phragmites australis leaves 2017-2019, with comparisons to the global Phragmites microbiome The chemistry of eolian quartz dust and the origin of chert Global Geochemical Database for Critical Metals in Black Shales