Property:Extended data description
From CSDMS
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(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 (https://csdms.colorado.edu/wiki/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.
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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. +
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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.
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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. +
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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. +
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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). +
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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. +
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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. +
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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. +
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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. +
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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. +
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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 (http://www.ncdc.noaa.gov/) 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. +
Gridded Population of the World, version 3 (GPWv3) is the latest developments in the rendering of human populations in a common geo-referenced framework, produced by the Center for International Earth Science Information Network (CIESIN) of the Earth Institute at Columbia University.
GPWv3 depicts the distribution of human population across the globe. It is the most detailed version of GPW to date with more than three times the amount of data as version 2, and includes population estimates to 2015.
Developed between 2003 and 2005, GPWv3 provides globally consistent and spatially explicit human population information and data for use in research, policy making, and communications.
GPWv3 incorporates a number of improvements to the two prior iterations of GPW. Input administrative data have been improved for nearly all of the 232 countries included in the dataset. (The number of administrative units has increased three-fold since GPWv2 and twenty-fold since GPWv1.) Additionally, the input data years have been updated for over two-thirds of the countries. The population data estimates, previously only available for 1990 and 1995, are also now provided for the period 1990–2015, by quinquennial years. The population estimates for 2005, 2010, and 2015 were produced in collaboration with the United Nations Food and Agriculture Programme (FAO) as GPW: Future Estimates. Finally, the map collection has been vastly expanded to include population density, and sub-national administrative boundary maps at country, continental, and global levels. +
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HYDRO1k is a geographic database developed to provide comprehensive and consistent global coverage of topographically derived data sets, including streams, drainage basins and ancillary layers derived from the USGS' 30 arc-second digital elevation model of the world (GTOPO30). HYDRO1k provides a suite of geo-referenced data sets, both raster and vector, which will be of value for all users who need to organize, evaluate, or process hydrologic information on a continental scale.
Developed at the U.S. Geological Survey's Center for Earth Resources Observation and Science (EROS), the HYDRO1k project's goal is to provide to users, on a continent by continent basis, hydrologically correct DEMs along with ancillary data sets for use in continental and regional scale modeling and analyses. +
HydroSHEDS is a mapping product that provides hydrographic information for regional and global-scale applications in a consistent format. It offers a suite of geo-referenced data sets (vector and raster) at various scales, including river networks, watershed boundaries, drainage directions, and flow accumulations. HydroSHEDS is based on high-resolution elevation data obtained during a Space Shuttle flight for NASA's Shuttle Radar Topography Mission (SRTM).
The goal of developing HydroSHEDS was to generate key data layers to support regional and global watershed analyses, hydrological modeling, and freshwater conservation planning at a quality, resolution and extent that had previously been unachievable. Available resolutions range from 3 arc-second (approx. 90 meters at the equator) to 5 minute (approx. 10 km at the equator) with seamless near-global extent. +
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International Bathymetric Chart of the Arctic Ocean (IBCAO). The goal of this initiative is to develop a digital data base that contains all available bathymetric data north of 64 degrees North, for use by mapmakers, researchers, and others whose work requires a detailed and accurate knowledge of the depth and the shape of the Arctic seabed.
IBCAO Version 3.0 represents the largest improvement since 1999 taking advantage of new data sets collected by the circum-Arctic nations, opportunistic data collected from fishing vessels, data acquired from US Navy submarines and from research ships of various nations. Built using an improved gridding algorithm, this new grid is on a 500 meter spacing, revealing much greater details of the Arctic seafloor than IBCAO Version 1.0 (2.5 km) and Version 2.0 (2.0 km). The area covered by multibeam surveys has increased from ~6 % in Version 2.0 to ~11% in Version 3.0. +
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Latest version (5.0)
The latest version of the "Global Map of Irrigation Areas" is version 5, which can be downloaded from this page. The documentation of the map includes an explanation of the methodology, information per country, an assessment of the map quality, and references to the background and history of the irrigation mapping project.
The map shows the amount of area equipped for irrigation around the year 2005 in percentage of the total area on a raster with a resolution of 5 minutes. Additional map layers show the percentage of the area equipped for irrigation that was actually used for irrigation and the percentages of the area equipped for irrigation that was irrigated with groundwater, surface water or non-conventional sources of water. An explanation of the different terminology to indicate areas under irrigation is given in this glossary. Please note that information for the additional layers on area actually irrigated or on the water source for irrigation was derived from statistical survey data (e.g. census reports). Therefore all grid cells belonging to the same statistical unit will have the same value. Consequently, the accuracy at pixel level will be very limited, depending on the size of the statistical unit.
Users are requested to refer to the map as follows: "Stefan Siebert, Verena Henrich, Karen Frenken and Jacob Burke (2013). Global Map of Irrigation Areas version 5. Rheinische Friedrich-Wilhelms-University, Bonn, Germany / Food and Agriculture Organization of the United Nations, Rome, Italy". +
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Layers (NetCDF) of monthly and yearly average suspended sediment flux in global rivers, predicted by the WBMsed model. +
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Lithology describes the geochemical, mineralogical, and physical properties of rocks. It plays a key role in many processes at the Earth surface, especially the fluxes of matter to soils, ecosystems, rivers, and oceans. The Lithological map of the World is based on the Global Lithological Map database v1.1 (GLiM, Hartmann and Moosdorf, 2012). GLiM represents the rock types of the emerged surface of the Earth using 1,235,400 polygons assembled from 92 regional geological maps, translated into lithological units using additional literature. According to the GLiM, the total surface of continents and islands is covered by 64 % sediments (a third of which is carbonates), 13% metamorphics, 7% plutonics, and 6% volcanics, and 10% are covered by water or ice. The high resolution of the GLiM allows observation of regional lithological distributions which often vary from the global average. The GLiM enables regional analysis of Earth surface processes at global scales. A coarse gridded version of the GLiM is available at the PANGEA Database (http://dx.doi.org/10.1594/PANGAEA.788537), the original GIS data are downloadable using this link (https://www.dropbox.com/s/9vuowtebp9f1iud/LiMW_GIS%202015.gdb.zip?dl=0). +
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Multiple general circulation models were run for paleoclimate simulations at 21, 6, and 0 (pre-inudstrial) ka. +
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NARWidth is composed of planform morphometric measurements of North American rivers at approximately mean discharge. It was created using image processing algorithms on Landsat TM and ETM+ imagery. NARWidth is intended to be used in a wide variety of scientific and engineering applications including hydrologic, hydraulic, and biogeochemical models. +
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NGDC is the US national archive for multibeam bathymetric data and presently holds over 15.7 million nautical miles of ship tracklines (1187 surveys) received from sources worldwide.
In addition to deepwater data, the multibeam database also includes hydrographic multibeam survey data from the NOS. Associated NOS data products, including 3D images and grids, are available via the NOS Hydrographic Survey Data Map Service. +
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NGDC's GEODAS Marine Trackline Geophysics database contains bathymetry, magnetics, gravity and seismic navigation data collected during marine cruises from 1953 to the present. Coverage is worldwide. Data sources include both US and foreign oceanographic institutions and government agencies.
This database is distributed both On-line and on DVD using the GEODAS Search and Retrieval software. Searches by geographic area, year of cruise, institution, platform, cruise, date or parameter are available. Downloads can be customized to area, parameter and format.
Digital data files are in the MGD77 exchange format, and contain a documentation header record and a series of data records. Header records document the content and structure of the data records. Data records contain geophysical data (bathymetry, magnetics, gravity and seismic shot-point ids) with time and position.
NGDC also archives analog geophysical data including seismic reflection and refraction, side-scan sonar, and other data types. Analog underway geophysical data are inventoried and searchable through the GEODAS Search and Retrieval software.
NGDC is pleased to accept contributions of underway geophysical data on almost any media, preferably in the MGD77 format. Any data received are in the international public domain, readily available globally to any interested individual or group. +
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NOAA was engaged in a program to compile Great Lakes bathymetric data and make them readily available to the public, especially to the communities concerned with Great Lakes science, pollution, coastal erosion, response to climate changes, threats to lake ecosystems, and health of the fishing industry. This program was managed by NGDC and relied on the cooperation of NOAA/Great Lakes Environmental Research Laboratory, NOAA/National Ocean Service, the Canadian Hydrographic Service, other agencies, and academic laboratories.
Compilation of new bathymetry for the Great Lakes was an important part of this program, carried out cooperatively between NOAA (NGDC and GLERL), and the Canadian Hydrographic Service. This new bathymetry provided a more detailed portrayal of lakefloor topography, and revealed some lakefloor features seen for the first time. +
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NOAA's National Centers for Environmental Information (NCEI) builds and distributes high-resolution, coastal digital elevation models (DEMs) that integrate ocean bathymetry and land topography to support NOAA's mission to understand and predict changes in Earth's environment, and conserve and manage coastal and marine resources to meet our Nation's economic, social, and environmental needs. They can be used for modeling of coastal processes (tsunami inundation, storm surge, sea-level rise, contaminant dispersal, etc.), ecosystems management and habitat research, coastal and marine spatial planning, and hazard mitigation and community preparedness.
Bathymetric, topographic, and shoreline data used in DEM compilation are obtained from various sources, including NCEI, the U.S. National Ocean Service (NOS), the U.S. Geological Survey (USGS), the U.S. Army Corps of Engineers (USACE), the Federal Emergency Management Agency (FEMA), and other federal, state, and local government agencies, academic institutions, and private companies. DEMs cell size ranges from 1/9 arc-second (~3 meters) to 36 arc-seconds (~1 km). +
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On-line access to information on historical (archived) water levels and streamflow. Using map-based or text-based searches, users can locate over 1200 hydrometric stations measuring water levels and view hydrographs of historical waer level and streamflow data.
Alternatively, users can use a separate tool to select and access historical data from over 2500 active stations and 5500 discontinued stations. In addition, a third tool allows users to generate historical water level and/or streamflow statistics for any of these (more than) 8000 stations. +
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OneGeology's aim is to create dynamic digital geological map data for the world. It is an international initiative of the geological surveys of the world who are working together to achieve this ambitious and exciting venture. Please follow the links in this section to find out more about OneGeology, what it is, why we are doing it and how such a big initiative can be achieved. +
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Presented are four companion digital models of the age, age uncertainty, spreading rates and spreading asymmetries of the world's ocean basins as geographic and Mercator grids with 2 minute resolution. The grids include data from all the major ocean basins as well as detailed reconstructions of back-arc basins. The age, spreading rate and asymmetry at each grid node is determined by linear interpolation between adjacent seafloor isochrons in the direction of spreading. Ages for ocean floor between the oldest identified magnetic anomalies and continental crust are interpolated by geological estimates of the ages of passive continental margin segments. The age uncertainties for grid cells coinciding with marine magnetic anomaly identifications, observed or rotated to their conjugate ridge flanks, are based on the difference between gridded age and observed age. The uncertainties are also a function of the distance of a given grid cell to the nearest age observation, and the proximity to fracture zones or other age discontinuities. Asymmetries in crustal accretion appear to be frequently related to asthenospheric flow from mantle plumes to spreading ridges, resulting in ridge jumps towards hotspots. We also use the new age grid to compute global residual basement depth grids from the difference between observed oceanic basement depth and predicted depth using two alternative age-depth relationships. The new set of grids helps to investigate prominent negative depth anomalies, which may be alternatively related to subducted slab material descending in the mantle or to asthenospheric flow. A combination of our digital grids and the associated relative and absolute plate motion model with seismic tomography and mantle convection model outputs represent a valuable set of tools to investigate geodynamic problems. +
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RESSED is a Microsoft® Access ® database containing information from the original Soil Conservation Service (SCS) datasheets (SCS Form 34) for the United States. The database is provided for download (i.e., this website does not contain tools for utilizing the RESSED database). The Subcommittee on Sedimentation hopes to provide updates to this database via periodic postings on this site. Such database improvements may be predicated on acquisition of adequate funding for RESSED.
Additionally, scanned copies of the original data sheets are available for selected viewing, downloading, or printing. The data sheets are in Adobe® Acrobat® Portable Document Format (PDF). +
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Sage contains a compilation of monthly mean river discharge data for over 3500 sites worldwide. The data sources are RivDis2.0, the United States Geological Survey, Brazilian National Department of Water and Electrical Energy, and HYDAT-Environment Canada. The period of record for each station is variable, from 3 years to greater than 100. All data is in m3/s. +
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TPXO6.2 is a medium-resolution, 1/4o x 1/4o global model developed by Gary Egbert and coworkers at Oregon State University. The model domain includes ocean cavities under the floating ice shelves. The principal assimilated data set is TOPEX/Poseidon (T/P) satellite radar altimetry, between +/-66o latitude. However, the model also includes patches for various "coastal" oceans, including the Antarctic (assimilating tide gauge data used in circum-Antarctic inverse model CADA00.10 and the Ross Sea height-based inverse model Ross_Inv_2002, and the Arctic (cf. the Arctic inverse model AOTIM-5). TPXO6.2 is one of the most accurate global tidal solutions, particularly for high latitudes since it utilizes recent Antarctic grounding line information and Antarctic and Arctic tide height data.
The load tide associated with TPXO6.2 (denoted "TPXO62_load") is a correction to TPXO6.2 to account for the deformation of the solid earth due to the added weight of water above it. The correction is usually a few percent of the local tidal amplitude. The load tide is used to correct the ocean tide to a geocentric tide height (e.g., the displacement of the ocean's free surface as measured by a satellite altimeter. The load tide is roughly out-of-phase with the ocean tide. Thus, adding the predicted load tide to the ocean tide leads to smaller tide heights. For altimetry, this means that the altimetrically-observed tide-forced variation of, say, an ice shelf surface, is typically less than the ocean tide. The load tide (or, more precisely, the "ocean self attraction and loading" term), is also required to correct the barotropic pressure gradient (i.e., sea surface slope) in the shallow water wave equations used to run dynamically based tide models.
The load tide is not the same as the earth's own body-tide response to lunar and solar gravitation: the body tide must be estimated separately from solid-earth models if required. However, the load tide is defined under continents as well as under the ocean: ocean tides force deformation of the earth's crust well inland of the coastal boundary (see the above figure).
TPXO62_load is distributed with a Matlab Graphical User Interface ("GUI") called "TMD" (the Tide Model Driver). TMD can be used to quickly access and browse the model, and to make load tide height predictions. The TMD package also contains scripted functions for use in batch-mode Matlab processing. For an overview of the GUI and scripts, view or download the README PDF file. For FORTRAN access, please go to the Oregon State "OTIS" web page.
TRMM, during its mission and broad sampling footprint between 35°N and 35°S, is providing some of the first detailed and comprehensive dataset on the four dimensional distribution of rainfall and latent heating over vastly undersampled oceanic and tropical continental regimes. Combined with concurrent measurement of the atmosphere's radiation budget, estimates of the total diabatic heating are being realized for the first time ever on a global scale.
TRMM will fill many gaps in our understanding of rainfall properties and their variation. These includes:
# frequency distributions of rainfall intensity and areal coverage;
# the partitioning of rainfall into convective and stratiform categories;
# the vertical distribution of hydrometeors (including the structure and intensity of the stratiform region bright band);
# variation of the timing of heaviest rainfall - particularly nocturnal intensification of large mesoscale convective systems over the oceans, and diurnal intensification of orographically and sea-breezed forced systems over land.
TRMM will enable mapping of larger time and space variations of rainfall in quasi-periodic circulation anomalies, such as the Madden-Julian oscillation in the western Pacific and ENSO over the broader Pacific basin. +
N
The 3 arc-second U.S. Coastal Relief Model (CRM) provides the first comprehensive view of the U.S. coastal zone, integrating offshore bathymetry with land topography into a seamless representation of the coast. The CRM spans the U.S. East and West Coasts, the northern coast of the Gulf of Mexico, Puerto Rico, and Hawaii, reaching out to, and in places even beyond, the continental slope.
Bathymetric data sources include the U.S. National Ocean Service Hydrographic Database, the U.S. Geological Survey (USGS), the Monterey Bay Aquarium Research Institute, the U.S. Army Corps of Engineers, and various other academic institutions. Topographic data are from the USGS and the Shuttle Radar Topography Mission (SRTM). Volumes 3 through 5 also use bathymetric contours from the International Bathymetric Chart of the Caribbean Sea and the Gulf of Mexico project. +
C
The CGIAR-CSI GeoPortal is able to provide SRTM 90m Digital Elevation Data for the entire world. The SRTM digital elevation data, produced by NASA originally, is a major breakthrough in digital mapping of the world, and provides a major advance in the accessibility of high quality elevation data for large portions of the tropics and other areas of the developing world. The SRTM digital elevation data provided on this site has been processed to fill data voids, and to facilitate it's ease of use by a wide group of potential users. This data is provided in an effort to promote the use of geospatial science and applications for sustainable development and resource conservation in the developing world. Digital elevation models (DEM) for the entire globe, covering all of the countries of the world, are available for download on this site. The SRTM 90m DEM's have a resolution of 90m at the equator, and are provided in mosaiced 5 deg x 5 deg tiles for easy download and use. All are produced from a seamless dataset to allow easy mosaicing. These are available in both ArcInfo ASCII and GeoTiff format to facilitate their ease of use in a variety of image processing and GIS applications. Data can be downloaded using a browser or accessed directly from the ftp site. +
D
The Dartmouth Flood Observatory uses orbital remote sensing to detect, measure, and map river discharge and river flooding.
Water discharge is measured by the River Watch processor, based on a feed of NASA AMSR-E satellite microwave data. It produces a remote sensing signal that tracks river discharge at 2500+ carefully selected river measurement sites.
Flooding is monitored by the MODIS sensors, to map floods as they occurred. +
E
The Data Catalog is a place to discover experimental datasets. Here, you can find metadata (following standardized Dublin Core guidelines) to maximize discoverability of your experimental datasets or use search for existing datasets based on metadata categories. +
G
The GIMMS (Global Inventory Modeling and Mapping Studies) data set is a normalized difference vegetation index (NDVI) product available for a 25 year period spanning from 1981 to 2006. The data set is derived from imagery obtained from the Advanced Very High Resolution Radiometer (AVHRR) instrument onboard the NOAA satellite series 7, 9, 11, 14, 16 and 17. This is an NDVI dataset that has been corrected for calibration, view geometry, volcanic aerosols, and other effects not related to vegetation change. +
The GRDC is an international archive of data up to 200 years old, and fosters multinational and global long-term hydrological studies. Originally established two decades ago, the aim of the GRDC is to help earth scientists analyse global climate trends and assess environmental impacts and risks. Positioned as a facilitator for exchanges between data providers and data users, the GRDC has become a focal point for international cooperation. Researchers, universities and other organisations make use of the facilities available for research programmes and projects.
The Global Runoff Database at GRDC is a unique collection of river discharge data collected at daily or monthly intervals from more than 7300 stations in 156 countries. This adds up to around 280 000 station-years with an average record of 38 years. The GRDC provides discharge data and data products for non-commercial applications.
The GRDC operates under the auspices of the World Meteorological Organisation (WMO) and supports research on global climate change and integrated water resources management. The German Federal Institute of Hydrology (Bundesanstalt für Gewässerkunde or BfG) hosts the GRDC in Koblenz near the confluence of the Moselle and Rhine Rivers. +
The GSHHG is a high-resolution geography data set, amalgamated from two databases in the public domain: World Vector Shorelines (WVS) and CIA World Data Bank II (WDBII). The former is the basis for shorelines while the latter is the basis for lakes, although there are instances where differences in coastline representations necessitated adding WDBII islands to GSHHG. The WDBII source also provides political borders and rivers. GSHHG data have undergone extensive processing and should be free of internal inconsistencies such as erratic points and crossing segments. The shorelines are constructed entirely from hierarchically arranged closed polygons.
GSHHG combines the older GSHHS shoreline database with WDBII rivers and borders, available in either ESRI shapefile format or in a native binary format. Geography data are in five resolutions: crude(c), low(l), intermediate(i), high(h), and full(f). Shorelines are organized into four levels: boundary between land and ocean (L1), boundary between lake and land (L2), boundary between island-in-lake and lake (L3), and boundary between pond-in-island and island (L4). +
The Global Human Settlement Layer (GHSL) project is supported by European Commission, Joint Research Center and Directorate-General for Regional and Urban Policy. The GHSL produces new global spatial information, evidence-based analytics, and knowledge describing the human presence in the planet. The GHSL relies on the design and implementation of new spatial data mining technologies allowing to process automatically and extract analytics and knowledge from large amount of heterogeneous data including: global, fine-scale satellite image data streams, census data, and crowd sources or volunteering geographic information sources. Spatial data reporting objectively and systematically about the presence of population and built-up infrastructures are necessary for any evidence-based modelling or assessing of i) human and physical exposure to threats as environmental contamination and degradation, natural disasters and conflicts, ii) impact of human activities on ecosystems, and iii) access to resources. The project produces thematic information and evidence-based analytical knowledge supporting the implementation of EU regional urban policy and the 4 international post-2015 frameworks, namely: Sustainable Development Goals, Global Urban Agenda, Climate Change and the Sendai Framework for Disaster Risk Reduction. Also, the project supports international scientific partnerships facilitating science-policy interface in the frame of the Group of Earth Observation (GI-21: Human Planet Initiative https://www.earthobservations.org/activity.php?id=51 ), and bi-lateral scientific collaborations with space agencies and scientific organizations of Brazil, China and South Africa.
This data package contains an assessment of the REGIOOECD “degree of urbanization” model using as input the population GRID cells in four epochs (2015, 2000, 1990, and 1975). +
The Global Seismic Hazard Assessment Program (GSHAP) was launched in 1992 by the International Lithosphere Program (ILP) with the support of the International Council of Scientific Unions (ICSU), and endorsed as a demonstration program in the framework of the United Nations International Decade for Natural Disaster Reduction (UN/IDNDR).
In order to mitigate the risk associated to the recurrence of earthquakes, the GSHAP promotes a regionally coordinated, homogeneous approach to seismic hazard evaluation; the ultimate benefits are improved national and regional assessments of seismic hazards, to be used by national decision makers and engineers for land use planning and improved building design and construction. +
H
The HWSD is a 30 arc-second raster database with over 16000 different soil mapping units that combines existing regional and national updates of soil information worldwide (SOTER, ESD, Soil Map of China, WISE) with the information contained within the 1:5 000 000 scale FAO-UNESCO Soil Map of the World (FAO, 19711981).
The resulting raster database consists of 21600 rows and 43200 columns, which are linked to harmonized soil property data. The use of a standardized structure allows for the linkage of the attribute data with the raster map to display or query the composition in terms of soil units and the characterization of selected soil parameters (organic Carbon, pH, water storage capacity, soil depth, cation exchange capacity of the soil and the clay fraction, total exchangeable nutrients, lime and gypsum contents, sodium exchange percentage, salinity, textural class and granulometry).
26 March, 2009 - Version 1.1 now includes SOTER/SOTWIS data for The Democratic Republic of the Congo, Burundi, Rwanda, Senegal, and Gambia.
Reliability of the information contained in the database is variable: the parts of the database that still make use of the Soil Map of the World such as North America, Australia, West Africa and South Asia are considered less reliable, while most of the areas covered by SOTER databases are considered to have the highest reliability (Central and Southern Africa, Latin America and the Caribbean, Central and Eastern Europe). +
