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<br> (In roll-out stage March 2014) ''Introduction'' Word-based data are pervasive in the geosciences, even in the field of numerical modeling. Parameters and units, materials, processes, events are all identified linguistically. For example, in the context of numerical modeling for earth surface dynamics the CSDMS Standard Names ( documents syntaxes used for parameter word-based namings. As a contribution to earth surface modeling and data handling, a comprehensive vocabulary of earth materials is presented here. Geomaterials include soils, sediments, rocks, biogenic buildups, ice and snow, and man-moved and man-made materials. The vocabulary is presented as a number of resources, including an ontology document which is a subset of the total vocabulary structure. A paper on the vocabulary is being finalized. ''Building the Vocabulary'' The vocabulary is computed from a corpus of glossaries, dictionaries, thesauri, ontologies, classifications. It was necessary to compute it because of the great number of geomaterials terms now available – estimated to be 10^4. Manual efforts to create a structured vocabulary through ontologies have encompassed only ~300 terms with rudimentary relationships in several years of work (Geosciml 2012). By computing the vocabulary, quantitative linguistic measures of concept distance and scope can also be made. The corpora used here were sourced from authoritative institutions such as British Geological Survey, US National Aeronautical and Space Agency (NASA), US Geological Survey (USGS), Society for Sedimentary Geology, CSIRO Australia, US Federal Geographic Data Committee, Center for Deep Earth Exploration (CDEX) in Japan, and the World Meteorological Organization (WMO). At last count there were 962 nodes (concepts) being served, and 1126 'strong words' from processing these corpora. ''Components'' Please see the detailed documentation that is in the served zip file. The vocabulary comes in three parts - general components, vocab for the geology ('litho') and cryology ('cryo') subthemes. The tallies are: 2315 strongwords, 836 lithology concepts, 16 corpora, ##. (i) A table of geomaterials concepts with their names, definitions, relationships, metrics and metadata. (ii) Tables of ‘strong words’ and weak words (the ‘stop list’) that are involved in describing the geomaterials concepts. The strong words are accompanied by frequency metrics, the sets of words which they associate with, levenstein variants, and stemmed morphologies. The strongwords are those that occur in the names of geomaterials concepts and are not in the stop-list. (iii) A formal ontology of subsumption relations (i.e., related, synonym, broader, narrower) expressed using SKOS and RDF logic systems in TTL syntax. (iv) (TBA) A semantic net of subsumption relations, and also quantitative strengths on the links between them. ''Use cases'' The vocabulary components provide a large resource which are needed for downstream software applications such as query mediation, semantic crosswalk, disambiguation, databasing. (i) A query can be launched using a set of terms (e.g., “feldspar-bearing sediments with glauconite”). The query is using local vocabulary and could alternatively we written “feldspathic sediments with verdine”. A ‘smart search’ (‘concept search’) drawing on a semantic net resource is able to search for both expressions – and also narrower ones such as “glauconitic albitic sands”. This is ‘query mediation’ and ‘query extension’. (ii) Crosswalks relate and compare two concepts. How close are they, do they subsume, what are their neighbours ? (iii) Disambiguation is a similar concept: given a homonym like “caterpillar”, animal and tractor can be distinguished by their typical word-associates in the text, with the patterns defined in a structured vocabulary like that served here.  
A data set of observed daily and monthly averaged precipitation, maximum and minimum temperature, gridded to a 1/16° (~6km) resolution that spans the entire country of Mexico, the conterminous U.S. (CONUS), and regions of Canada south of 53º N for the period 1950-2013. The dataset improves previous products in spatial extent, orographic precipitation adjustment over Mexico and parts of Canada, and reduction of transboundary discontinuities. The precipitation is adjusted for orographic effects using an elevation-aware 1981-2010 precipitation climatology. Because of the consistent gridding methodology, the current product reduces transboundary discontinuities making it suitable for estimating large-scale hydrometeorologic phenomena. Also included are daily wind data from the National Centers for Environmental Prediction - National Centers for Atmospheric Research (NCEP - NCAR) resampled to the same grid as temperature and precipitation. Hydrometeorological states and fluxes are simulated over the full period 1950-2013 using the Variabile Infiltration Capacity (VIC) model v.4.1.2.c.  +
A great part of the coral reef resources in the world are in danger of destruction due to over exploitation, degradation of habitat and, possibly, changes in global climate. Globally, the resulting loss of income from fisheries is estimated to be billions of dollars a year and affects many millions of people. Few figures are available to indicate the sustainable yields that might be extracted for different reef types, current and potential yields of different reef species, how yields are affected by declining reef health and loss of productive capacity, and the value of non-extractive uses of reefs (such as tourism). Sophisticated methods to quantify the deterioration of coral reefs have been initiated in some areas, while hardly any assessment or monitoring activities exist in others. Information from these activities is usually published in the primary scientific literature and may not be readily available or understood by a non-technical reader. A larger body of information has been compiled in technical reports, which are generally for limited distribution. This makes it difficult for the people tasked with managing coral reefs to obtain the information needed for good management even when comprehensive information exists. ReefBase gathers available knowledge about coral reefs into one information repository. It is intended to facilitate analyses and monitoring of coral reef health and the quality of life of reef-dependent people, and to support informed decisions about coral reef use and management. ReefBase is the official database of the Global Coral Reef Monitoring Network (GCRMN), as well as the International Coral Reef Action Network (ICRAN). The ReefBase Project is housed at the WorldFish Center in Penang, Malaysia, with funding through ICRAN from the United Nations Foundation (UNF). Key Objectives of ReefBase * Develop a relational database and information system for structured information on coral reefs and their resources that will serve as a computerized encyclopedia and analytical tool for use in reef management, conservation and research. * Provide key information to support decision-making by fisheries and environmental managers in developing countries, especially those concerned with improving the livelihoods of poor fishers. * Collaborate with other national, regional, and international databases, and GIS facilities relating to reefs, and provide a means of comparing and interpreting information at the global level. * Develop and distribute analytical routines for ReefBase that will make full use of the information and ensure appropriate interpretation and synthesis. * Serve as the central repository for data of the Global Coral Reef Monitoring Network (GCRMN) and the International Coral Reef Action Network (ICRAN). * Define criteria for reef health and use them to refine procedures for coral reef assessments and to determine coral reef status at the regional and global level. * Determine the relationships among coral reef health, fishery production and the quality of life of people dependent on reefs.  
A web portal for Global River and Delta Systems, Source-to-Sink references on google map. The underlying database contains for a selected set of rivers their length, basin area, water discharge, sediment load, sediment yield, delta size, related publications and an elevation profile of each of the selected rivers.  +
Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). The ASTER GDEM was created by stereo-correlating the 1.3 million scene ASTER VNIR archive, covering the Earth's land surface between 83N and 83S latitudes. The GDEM is produced with 30 meter postings, and is formatted in 1 x 1 degree tiles as GeoTIFF files. Each GDEM file is accompanied by a Quality Assessment file, either giving the number of ASTER scenes used to calculate a pixel's value, or indicating the source of external DEM data used to fill the ASTER voids.  +
Aerial images of Fraser GST zone at low flow (about 700 m3/s). The images and the analysis are associated with the publication "Advance, retreat, and halt of abrupt gravel-sand transitions in alluvial rivers" in Geophysical Research Letters.  +
An output of the Global Land Use Dynamics Model (GLUDM). Spatially explicit global estimates of cropland area between 1960-2099. Yearly time steps in individual NetCDF files. The GLUDM is based on pixel-specific regression between historic land use changes and global population. Land use expansion and abandonment is governed by environmental and land use restrictions (e.g altitude and urbanization). Fro more detailes see: Haney, N., Cohen, S. (2015), Predicting 21st century global agricultural land use with a spatially and temporally explicit regression-based model. Applied Geography, 62: 366-376. doi:10.1016/j.apgeog.2015.05.010  +
Data from spaceborne light detection and ranging (lidar) opens the possibility to map forest vertical structure globally. Presented here is a wall-to-wall, global map of canopy height at 1-km spatial resolution, using 2005 data from the Geoscience Laser Altimeter System (GLAS) aboard ICESat (Ice, Cloud, and land Elevation Satellite).  +
Data from: Hooshmand, A., A. R. Horner-Devine, and M. P. Lamb (2015), Structure of turbulence and sediment stratification in wave-supported mud layers, J. Geophys. Res. Oceans, 120, doi:10.1002/ 2014JC010231. Abstract: We present results from laboratory experiments in a wave flume with and without a sediment bed to investigate the turbulent structure and sediment dynamics of wave-supported mud layers. The presence of sediment on the bed significantly alters the structure of the wave boundary layer relative to that observed in the absence of sediment, increasing the TKE by more than a factor of 3 at low wave orbital velocities and suppressing it at the highest velocities. The transition between the low and high-velocity regimes occurs when Re_delta = 450, where Re_delta is the Stokes Reynolds number. In the low-velocity regime (Re_delta < 450) the flow is significantly influenced by the formation of ripples, which enhances the TKE and Reynolds stress and increases the wave boundary layer thickness. In the high-velocity regime (Re_delta > 450) the ripples are significantly smaller, the near-bed sediment concentrations are significantly higher and density stratification due to sediment becomes important. In this regime the TKE and Reynolds stress are lower in the sediment bed runs than in comparable runs with no sediment. The regime transition at Re_delta=450 appears to result from washout of the ripples and increased concentrations of fine sand suspended in the boundary layer, which increases the settling flux and the stratification near the bed. The increased stratification damps turbulence, especially near the top of the high-concentration layer, reducing the layer thickness. We anticipate that these effects will influence the transport capacity of wave-supported gravity currents on the continental shelf.  +
Dataset of measured long-term (> 1 year) average catchment sediment yield measurements for 683 African rivers. Measurements were either derived from observations at a gauging station or from sedimentation rates in reservoirs. Details on the data collection procedure and qualtity assessment can be found in: Vanmaercke M, Poesen J, Broeckx J, Nyssen J (2014) Sediment Yield in Africa. Earth-Science Reviews 136: 350–368. When using data from this dataset, please refer to this article, as well as to the original source of the data.  +
Derived from the early to mid-1990s Landsat Thematic Mapper satellite data, the National Land Cover Data (NLCD) is a 21-class land cover classification scheme applied consistently over the United States. The spatial resolution of the data is 30 meters and mapped in the Albers Conic Equal Area projection, NAD 83. The NLCD are provided on a state-by-state basis. The state data sets were cut out from larger "regional" data sets that are mosaics of Landsat TM scenes. At this time, all of the NLCD state files are available for free download as 8-bit binary files and some states are also available on CD-ROM as a Geo-TIFF.  +
E-OBS is a daily gridded observational dataset for precipitation and temperature in Europe based on ECA&D information. The full dataset covers the period 1950-2009. It has originally been developed as part of the ENSEMBLES project (EU-FP6) and is now maintained and elaborated as part of the EURO4M project (EU-FP7).  +
ETOPO1 is a 1 arc-minute global relief model of Earth's surface that integrates land topography and ocean bathymetry. It was built from numerous global and regional data sets, and is available in "Ice Surface" (top of Antarctic and Greenland ice sheets) and "Bedrock" (base of the ice sheets) versions.  +
Field and laboratory data related to Earth-surface Dynamics. Topics include channel morphology, dam removal, debris flows, stratigraphy, stream restoration, subsurface architecture, and more. Locations include the Angelo Coast Reserve, the Eel River, St. Anthony Falls Laboratory, and the Richmond Field Station.  +
GLOBALSOD represents a collection of daily data from over 10000 weather stations located around the world. The data is available here as a dataset, including an interactive data viewer and downloadable data files. The following information describes the global surface summary of day data built monthly by the National Climatic Data Center (NCDC) in Asheville, NC. The hourly data used in building these daily summaries are obtained from the Air Weather Service (AWS) Global Climatology Division, located in the Federal Climate Complex with NCDC. The latest month of the daily summary data is placed on line by NCDC for easy access and download by outside users, and is normally available about 1 month after the end of the data month. Over 8000 stations' data are typically included each month. They are accessible through our mosaic/www server ( or through direct ftp connection. Other periods of the summary of day data (up to 20 years or more) can be obtained off-line from NCDC. The daily elements included in the dataset (as available from each station; not all stations have all the different variables at all times) are: * Mean temperature (.1 Fahrenheit) * Mean dew point (.1 Fahrenheit) * Mean sea level pressure (.1 mb) * Mean station pressure (.1 mb) * Mean visibility (.1 miles) * Mean wind speed (.1 knots) * Maximum sustained wind speed (.1 knots) * Maximum wind gust (.1 knots) * Maximum temperature (.1 Fahrenheit) * Minimum temperature (.1 Fahrenheit) * Precipitation amount (.01 inches) * Snow depth (.1 inches) * Indicator for occurrence of: ** Fog ** Rain ** Snow ** Hail ** Thunder ** Tornado/Funnel Cloud  +
GLOBE is a project to develop the best available 30-arc-second (nominally 1 kilometer) global digital elevation data set. This version of GLOBE contains data from 11 sources, and 17 combinations of source and lineage. It continues much in the tradition of the National Geophysical Data Center's TerrainBase (FGDC 1090), as TerrainBase served as a generally lower-resolution prototype of GLOBE data management and compilation techniques. The GLOBE mosaic has been compiled onto CD-ROMs for the international user community. It is also available from the World Wide Web (linked from the online linkage noted above and anonymous ftp. Improvements to the global model are anticipated, as appropriate data and/or methods are made available. In addition, individual contributions to GLOBE (several areas have more than one candidate) should become available at the same website. GLOBE may be used for technology development, such as helping plan infrastructure for cellular communications networks, other public works, satellite data processing, and environmental monitoring and analysis. GLOBE prototypes (and probably GLOBE itself after its release) have been used to help develop terrain avoidance systems for aircraft. In all cases, GLOBE data should be treated as any potentially useful but guaranteed imperfect data set. Mission- or life-critical applications should consider the documented artifacts, as well as likely undocumented imperfections, in the data.  +
GTOPO30 is a global digital elevation model (DEM) with a horizontal grid spacing of 30 arc seconds (approximately 1 kilometer). GTOPO30 was derived from several raster and vector sources of topographic information.  +
General Bathymetric Chart of the Oceans (GEBCO). The GEBCO_08 Grid is a continuous terrain model (latest version - Sept 2011) for ocean and land with a spatial resolution of 30 arc-seconds. The bathymetry data were produced by combining the published Smith and Sandwell global topographic grid between latitudes 80°N and 81°S (version 11.1, September, 2008) with a database of over 290 million bathymetric soundings. For the area north of Antarctica, the land data are based on the 1-km averages of topography derived from version 2.0 of the US Geological Survey SRTM30 gridded digital elevation model data product created with data from the US National Aeronautics and Space Administration (NASA) Shuttle Radar Topography Mission and, for high latitudes were SRTM data are not available, the US Geological Survey GTOPO30 data set. For the area around Antarctica, the land data are taken from the Geoscience Laser Altimeter System (GLAS) instrument on the Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry digital elevation model. The complete data sets give global coverage and each file consists of 21,600 rows x 43,200 columns, resulting in 9,331,200,000 data points. The data start at the Northwest corner of the files, i.e. for the global files, position 89° 59‟ 45‟‟N, 179° 59‟ 45‟‟W and are arranged in latitudinal bands of 360 degrees x 120 points/degree = 43,200 values. The data range eastward from 179° 59‟ 45‟‟W to 179° 59‟ 45‟‟E. Thus, the first band contains 43,200 values for 89° 59‟ 45‟‟N, then followed by a band of 43,200 values at 89°59‟ 15‟‟N and so on at 30 arc-second latitude intervals down to 89° 59‟ 45‟‟S.  +
GlobCover is an ESA initiative which began in 2005 in partnership with JRC, EEA, FAO, UNEP, GOFC-GOLD and IGBP. The aim of the project was to develop a service capable of delivering global composites and land cover maps using as input observations from the 300m MERIS sensor on board the ENVISAT satellite mission. ESA makes available the land cover maps, which cover 2 periods: December 2004 - June 2006 and January - December 2009.  +
Global ocean bathymetry estimated from sea-surface satellite altimetry (Geosat and ERS-1) measurements and constrained by ship depth measurements.  +