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). +
The HydroLAKES database was designed as a digital map repository to include all lakes with a surface area of at least 10 ha. Version 1 comprises the shoreline polygons of 1,427,688 individual lakes. HydroLAKES aims to be as comprehensive and consistent as possible at a global scale and contains both freshwater and saline lakes, including the Caspian Sea, as well as human-made reservoirs and regulated lakes. The HydroLAKES database was created by compiling, correcting, and unifying several near-global and regional datasets, foremost the SRTM Water Body Data (SWBD; Slater et al., 2006) for regions from 56˚S to 60˚N, and CanVec (Natural Resources Canada, 2013) for most North American lakes. Map generalization methods were applied and some polygon outlines were smoothed during the mapping process to ensure spatial consistency of the data. The resulting map scale is estimated to be between 1:100,000 and 1:250,000 for most lakes globally, with some coarser ones at 1:1 million. +
I
The ICE-5G (VM2) model mathematically analyses glacio-isostatic adjustment processes and provides model data on global ice sheet coverage, ice thickness and paleotopography at 10 min spatial resolution for 21ka and 0ka, and at 1degree spatial resolution for intervals in between these snapshots. These are NETCDF files. +
N
The Indian National River Linking Project (NRLP), or Indian Rivers Interlinking project (IRI), proposes a major redistribution of water resources over the Indian subcontinent. A large engineering effort is proposed to redistribute monsoonal water from the Himalayas and foothills, store water in reservoirs, and route it via canals ("links") to the drier regions of Southern India. A total of 29 links and 43 dams and barrages are proposed as part of the project.
The plan would provide water resources for agriculture, drinking water and industrial use to a growing population in central and southern India, while potentially improving flood control in the northern and mountainous areas. The project would also result in a major reorganization of watersheds, with possible impacts on ecosystems and the environment. There would be impacts on trans-boundary rivers.
Here provided are two databases: (1) the dams database, with locations, operating specifications, sources, and notes on population expected to be displaced; and (2) the canals database, with locations, operating specifications, and further notes. The databases are available as shapefiles for GIS visualization - click a feature to see its database information. A "rivers" shapefile is also available for help in generating visualizations. Note that the rivers are not currently labeled in the shapefile. Raw txt/csv format is also available for the canals and dams databases. An annotated reference list is included to give specifics on the sources from which each number was obtained and/or calculated.
The databases are constructed from hundreds of government reports, geo-referenced maps, planning and design documents and Open Street Map data. For full methodology and calculations regarding displaced populations, see the accompanying manuscript: Higgins et al., 2017. For the graph database tool used to calculate basin connectivity changes and water discharge changes for given river mouths, see the github page: https://github.com/sahiggin/NRLP .
M
The MERIT DEM was developed by removing multiple error components (absolute bias, stripe noise, speckle noise, and tree height bias) from the existing spaceborne DEMs (SRTM3 and AW3D). It represents the terrain elevations at a 3sec resolution (~90m at the equator), and covers land areas between 90N-60S. The data is freely available for research and education purpose. +
N
The Multi-Resolution Land Characteristics Consortium (MRLC) has completed the National Land Cover Database (NLCD) 2001 products for the conterminous United States, Hawaii, Alaska and Puerto Rico at 30 m cell resolution. The NLCD 2001 products (land cover, impervious surface and canopy density) were generated from a standardized set of data layers mosaicked by mapping zone. Typical zonal layers included multi-season Landsat 5 and Landsat 7 imagery centered on a nominal collection year of 2001, and Digital Elevation Model based derivatives at 30 meters spatial resolution. NLCD 2001 used an improved classification algorithm from NLCD 1992, resulting in a more precise rendering of spatial boundaries between 16 classes of land cover (additional classes are available in coastal areas and Alaska only). +
The National Elevation Dataset (NED) is the primary elevation data product of the USGS. The NED is a seamless dataset with the best available raster elevation data of the conterminous United States, Alaska, Hawaii, and territorial islands. The NED is updated on a nominal two month cycle to integrate newly available, improved elevation source data. All NED data are public domain. The NED is derived from diverse source data that are processed to a common coordinate system and unit of vertical measure. NED data are distributed in geographic coordinates in units of decimal degrees, and in conformance with the North American Datum of 1983 (NAD 83). All elevation values are in meters and, over the conterminous United States, are referenced to the North American Vertical Datum of 1988 (NAVD 88). The vertical reference will vary in other areas. NED data are available nationally (except for Alaska) at resolutions of 1 arc-second (about 30 meters) and 1/3 arc-second (about 10 meters), and in limited areas at 1/9 arc-second (about 3 meters). In most of Alaska, only lower resolution source data are available. As a result, most NED data for Alaska are at 2-arc-second (about 60 meters) grid spacing. Part of Alaska is available at the 1- and 1/3-arc-second resolution, and plans are in development for a significant improvement in elevation data coverage of the state. +
The National Hydrography Dataset (NHD) is the surface-water component of The National Map. The NHD is a comprehensive set of digital spatial data that represents the surface water of the United States using common features such as lakes, ponds, streams, rivers, canals, streamgages, and dams. Polygons are used to represent area features such as lakes, ponds, and rivers; lines are used to represent linear features such as streams and smaller rivers; and points are used to represent point features such as streamgages and dams. Lines also are used to show the water flow through area features such as the flow of water through a lake. The combination of lines is used to create a network of water and transported material flow to allow users of the data to trace movement in downstream and upstream directions. +
The National Ocean Service (NOS) Hydrographic Data Base (NOSHDB), maintained by NGDC in conjunction with NOS, provides extensive survey coverage of the coastal waters and Exclusive Economic Zone (EEZ) of the United States and its territories. The NOSHDB contains data digitized from smooth sheets of hydrographic surveys completed between 1851 and 1965, and from survey data acquired digitally on NOS survey vessels since 1965.
Over 76 million soundings from over 6600 surveys are now included in the NOSHDB. These data may be searched and downloaded online using the Hydrographic Survey Data Map Service (an interactive map and data discovery tool at NGDC; http://map.ngdc.noaa.gov/website/mgg/nos_hydro/viewer.htm). The NOSHDB data with search and retrieval software are also available on a DVD-ROM or CD-ROM set.
Data products from NOS surveys, including BAG files, descriptive reports (DRs), smooth sheet images, survey data images, textual gridded data, and sidescan sonar mosaics, are available for download from NGDC using the Hydrographic Survey Data Map Service. +
S
The Natural Resources Conservation Service (NRCS) - National Cartography and Geospatial Center (NCGC) previously archived and distributed the State Soil Geographic (STATSGO) Database. The STATSGO spatial and tabular data were revised and updated in 2006. STATSGO has been renamed to the U.S. General Soil Map (STATSGO2). It is available for download from the Soil Data Mart (http://soildatamart.nrcs.usda.gov/).
The dataset was created by generalizing more detailed soil survey maps. Where more detailed soil survey maps were not available, data on geology, topography, vegetation, and climate were assembled, together with Land Remote Sensing Satellite (LANDSAT) images. Soils of like areas were studied, and the probable classification and extent of the soils were determined.
Map unit composition was determined by transecting or sampling areas on the more detailed maps and expanding the data statistically to characterize the whole map unit.
This dataset consists of geo-referenced vector and tabular digital data. The map data were collected in 1- by 2-degree topographic quadrangle units and merged into a seamless national dataset. It is distributed in state/territory and national extents. The soil map units are linked to attributes in the tabular data, which give the proportionate extent of the component soils and their properties.
The tabular data contain estimated data on the physical and chemical soil properties, soil interpretations, and static and dynamic metadata. Most tabular data exist in the database as a range of soil properties, depicting the range for the geographic extent of the map unit. In addition to low and high values for most data, a representative value is also included for these soil properties. +
P
The PSMSL was established in 1933, and is the global data bank for long term sea level change information from tide gauges. The PSMSL collect data from several hundred gauges situated all over the globe. As of December 2006, the database of the PSMSL contains over 55000 station-years of monthly and annual mean values of sea level from almost 2000 tide gauge stations around the world received from almost 200 national authorities. On average, approximately 2000 station-years of data are entered into the database each year. +
S
The SRTM Water Body Data files are a by-product of the data editing performed by the National Geospatial-Intelligence Agency (NGA) to produce the finished SRTM Digital Terrain Elevation Data Level 2 (DTED® 2). In accordance with the DTED® 2 specification, the terrain elevation data have been edited to portray water bodies that meet minimum capture criteria. Ocean, lake and river shorelines were identified and delineated. Lake elevations were set to a constant value. Ocean elevations were set to zero. Rivers were stepped down monotonically to maintain proper flow. After this processing was done, the shorelines from the one arc second (approx. 30-meter) DTED® 2 were saved as vectors in ESRI 3-D Shapefile format.
In most cases, two orthorectified image mosaics (one for ascending passes and one for descending passes) at a one arc second resolution were available for identifying water bodies and delineating shorelines in each 1 x1 cell. These were used as the primary source for water body editing. The guiding principle for this editing was that water must be depicted as it was in February 2000 at the time of the shuttle flight. A Landcover water layer and medium-scale maps and charts were used as supplemental data sources, generally as supporting evidence for water identified in the image mosaics. Since the Landcover water layer was derived mostly from Landsat 5 data collected a decade earlier than the Shuttle mission and the map sources had similar currency problems, there were significant seasonal and temporal differences between the depiction of water in the ancillary sources and the actual extent of water bodies in February 2000 in many instances. In rare cases, where the SRTM image mosaics were missing or unusable, Landcover was used to delineate the water in the SRTM cells. The DTED® header records for those cells are documented accordingly. +
The SSURGO database contains information about soil as collected by the National Cooperative Soil Survey over the course of a century. The information can be displayed in tables or as maps and is available for most areas in the United States and the Territories, Commonwealths, and Island Nations served by the USDA-NRCS. The information was gathered by walking over the land and observing the soil. Many soil samples were analyzed in laboratories. The maps outline areas called map units. The map units describe soils and other components that have unique properties, interpretations, and productivity. The information was collected at scales ranging from 1:12,000 to 1:63,360. More details were gathered at a scale of 1:12,000 than at a scale of 1:63,360. The mapping is intended for natural resource planning and management by landowners, townships, and counties. Some knowledge of soils data and map scale is necessary to avoid misunderstandings. +
The Shuttle Radar Topography Mission (SRTM) obtained elevation data on a near-global scale to generate the most complete high-resolution digital topographic database of Earth between 56 degrees south and 60 degrees north latitude. SRTM consisted of a specially modified radar system that flew onboard the Space Shuttle Endeavour during an 11-day mission in February of 2000.
NASA has released version 2 of the Shuttle Radar Topography Mission digital topographic data (also known as the "finished" version). Version 2 is the result of a substantial editing effort by the National Geospatial Intelligence Agency and exhibits well-defined water bodies and coastlines and the absence of spikes and wells (single pixel errors), although some areas of missing data ('voids') are still present. The Version 2 directory also contains the vector coastline mask derived by NGA during the editing, called the SRTM Water Body Data (SWBD), in ESRI Shapefile format.
Version 2.1 is a recalculation of the SRTM3 (nominal 90 meter sample spacing) version made by 3x3 averaging of the full resolution edited data. Version 2 had been generated by masking in edited samples from the lower-resolution publicly released by the NGA, and contained occasional artifacts, and in particular a slight vertical “banding” in databeyond 50° latitude. These have been eliminated in Version 2.1
SRTM data are distributed in two levels: SRTM1 (for the U.S. and its territories
and possessions) with data sampled at one arc-second intervals in latitude and
longitude, and SRTM3 (for the world) sampled at three arc-seconds. Three arc-second data are generated by three by three averaging of the one arc-second samples. +
The Southern Alaska Coastal Relief Model is a 24 arc-second digital elevation model ranging from 170° to 230° and 48.5° to 66.5° N. It integrates bathymetry and topography to represent Earth's surface and spans over the Gulf of Alaska, Bering Sea, Aleutian Islands, and Alaska's largest communities: Anchorage, Fairbanks, and Juneau. The relief model was built from a variety of source datasets acquired from the National Geophysical Data Center, National Ocean Service, United States Geological Survey, National Aeronautics and Space Administration, and other U.S. and international agencies.
The CRM provides a framework to enable scientists to model tsunami propagation and ocean circulation. In addition, it may be useful for benthic habitat research, weather forecasting, and environmental stewardship. +
R
The U.S. Geological Survey Real-Time Permafrost and Climate Monitoring Network in Arctic Alaska is a collaborative effort with BLM, U.S. Fish and Wildlife Service, private organizations and universities, all managed by USGS.
The network was established to provide high quality real-time environmental data to aid in land management decision making.
This real-time network is a subset of a larger U.S. Geological Survey permafrost and climate monitoring research network. Many of the stations are co-located with deep boreholes, thus forming the basis for comprehensive permafrost monitoring observatories. The objectives of the larger network include climate change detection, monitoring how permafrost and vegetation respond to climate change, and acquiring improved data for current permafrost characterization and impact assessment models. +
N
The United States Geological Survey (USGS) has collected water-resources data at approximately 1.5 million sites across the United States, Puerto Rico, and Guam.
The types of data collected are varied, but generally fit into the broad categories of surface water and ground water. Surface-water data, such as gage height (stage) and streamflow (discharge), are collected at major rivers, lakes, and reservoirs. Ground-water data, such as water level, are collected at wells and springs.
Water-quality data are available for both surface water and ground water. Examples of water-quality data collected are temperature, specific conductance, pH, nutrients, pesticides, and volatile organic compounds.
This web site serves current and historical data. Data are retrieved by category of data, such as surface water, ground water, or water quality, and by geographic area. Subsequent pages allow further refinement by selecting specific information and by defining the output desired.
Real-time data typically are recorded at 15-60 minute intervals, stored onsite, and then transmitted to USGS offices every 1 to 4 hours, depending on the data relay technique used. Recording and transmission times may be more frequent during critical events. Data from real-time sites are relayed to USGS offices via satellite, telephone, and/or radio and are available for viewing within minutes of arrival. (Note that all real-time data are provisional and subject to revision). +
W
The World Glacier Inventory contains information for over 100,000 glaciers through out the world. Parameters within the inventory include geographic location, area, length, orientation, elevation,and classification of morphological type and moraines. The inventory entries are based upon a single observation in time and can be viewed as a 'snapshot' of the glacier at this time. The core of this collection is data from the World Glacier Monitoring Service, Zurich. The development of the data product was funded through NOAA's Environmental Services Data and Information Management (ESDIM) program. +
The World Ocean Atlas 2001 (WOA01) contains ASCII data of statistics and objectively analyzed fields for one-degree and five-degree squares generated from World Ocean Database 2001 observed and standard level flagged data.
The ocean variables included in the atlas are: in-situ temperature, salinity, dissolved oxygen, apparent oxygen utilization, percent oxygen saturation, dissolved inorganic nutrients (phosphate, nitrate, and silicate), chlorophyll at standard depth levels, and plankton biomass sampled from 0 - 200 meters. +
The World Vector Shoreline (WVS) is a digital data file at a nominal scale of 1:250000, containing the shorelines, international boundaries and country names of the world. The World Vector Shoreline is a standard US Defense Mapping Agency (DMA) product that has been designed for use in many applications. The WVS is divided into ten ocean basin area files. Together the ten files form a seamless world, with the exception of Central America, where there is an overlap between the Western North Atlantic file and the Eastern North Pacific File.
The main source material for the WVS was the DMA's Digital Landmass Blanking (DLMB) data which was derived primarily from the Joint Operations Graphics and coastal nautical charts produced by DMA. The DLMB data consists of a land/water flag file on a 3 by 3 arc-second interval grid. This raster data set was converted into vector form to create the WVS. For areas of the world not covered by the DLMB data (e.g. the Arctic and Antarctic), the shoreline was taken from the best available hard copy sources at a preferred scale of 1:250000. The WVS data are stored in chain-node format, and include tags to indicate the landside/waterside of the shoreline. +
G
The basic concept adopted to develop this database is to integrate the best land cover data available, from local to global, into one single database using international standards; this task requires the harmonization among different layers and legends to create a consistent product.
Here are criteria and steps for the harmonization:
* absorb, overcome and minimize the thematic and spatio-temporal differences between individual databases;
* create an efficient and practical mechanism to harmonize various datasets using the land cover elements;
* use data fusion techniques to overcome some of the harmonization issues;
identify agreement/disagreement between a limited number of global dataset at pixel level;
* create land cover database;
* validate land cover database;
* develop a fully automated “procedure” to update the database when new datasets may become available. +
The fully-standardised 26 geomorphometric variables consist of layers that describe the (i) rate of change across the elevation gradient, using first and second derivatives, (ii) ruggedness, and (iii) geomorphological forms. The Geomorpho90m variables are available at 3 (~90 m) and 7.5 arc-second (~250 m) resolutions under the WGS84 geodetic datum, and 100 m spatial resolution under the Equi7 projection. They are useful for modelling applications in fields such as geomorphology, geology, hydrology, ecology and biogeography. +
M
The global Mixed Layer Depth (MLD) Climatologies available here are computed from more than 5 million individual profiles obtained from the National Oceanographic Data Center (NODC), from the World Ocean Circulation Experiment (WOCE) database, and from the ARGO program. Those are all the high vertical resolution data available since 1941 until 2008, including mechanical bathythermograph (MBT), expendable bathythermograph (XBT), conductivity-temperature-depth probes (CTD), and profiling floats (PFL).
The MLDs are estimated directly on individual profiles with data at observed levels. The MLD is defined through the threshold method with a finite difference criterion from a near-surface reference value. A linear interpolation between levels is then used to estimate the exact depth at wich the difference criterion is reached. The reference depth is set at 10 m to avoid a large part of the strong diurnal cycle in the top few meters of the ocean. The optimal temperature criterion is found to be 0.2 °C absolute difference from surface. The optimal one in density is 0.03 kg/m3 difference from surface.
Reduction of the data is done on a regular 2° by 2° grid for every month, by taking the median of all MLDs in each grid mesh. A slight smoothing is then applied to take account of the noisy nature of ship observations. The last step consisted into an optimal prediction of the missing data using ordinary kriging method. This interpolation was limited to a 1000 km radius disk containing at least 5 grid point values, leaving regions without values instead of filled by a doubtful interpolation. The advantage of kriging is that it is an exact interpolator, and an estimation error in the form of the kriging standard deviation, an analogy to the statistical standard deviation, is also provided. +
D
The global drainage direction map DDM30 is a raster map which describes the drainage directions of surface water with a spatial resolution of 30’ longitude by 30’ latitude. 66896 individual grid cells, covering the entire land surface of the globe (without Antarctica), are connected to each other by their respective drainage direction and are thus organized into drainage basins. Each cell can drain only into one of the eight neighboring cells.
DDM30 is based on
# the digital drainage direction map with a resolution of 5’ of Graham et al. (1999) for South America, Australia, Asia and Greenland,
# the HYDRO1k digital drainage direction map (as flow accumulation map) with a resolution of 1 km (USGS, 1999) for North America, Europe, Africa and Oceania (without Australia).
Both given base maps were up scaled to a resolution of 30’. +
O
The mission of the OpenTopography Facility is to:
-Democratize online access to high-resolution (meter to sub-meter scale), Earth science-oriented, topography data acquired with LiDAR and other technologies.
-Harness cutting edge cyberinfrastructure to provide Web service-based data access, processing, and analysis capabilities that are scalable, extensible, and innovative.
-Promote discovery of data and software tools through community populated metadata catalogs.
-Partner with public domain data holders to leverage OpenTopography infrastructure for data discovery, hosting and processing.
-Provide professional training and expert guidance in data management, processing, and analysis.
-Foster interaction and knowledge exchange in the Earth science LiDAR user community.
The OpenTopography Facility is based at the San Diego Supercomputer Center at the University of California, San Diego and is operated in collaboration with colleagues at UNAVCO and in the School of Earth and Space Exploration at Arizona State University. Core operational support for OpenTopography comes from the National Science Foundation Earth Sciences: Instrumentation and Facilities Program (EAR/IF) and the Office of Cyberinfrastructure. In addition, we receive funding from the NSF and NASA to support various OpenTopography related research and development activities. OpenTopography was initially developed as a proof of concept cyberinfrastructure in the Earth sciences project as part of the NSF Information and Technology Research (ITR) program-funded Geoscience Network (GEON) project. +
3
The overall objective of the project is to combine radar and lidar remote sensing to characterize the forested landscapes in 3D. The science products generated by Simard and collaborators have four main components:
1 Global scale mapping of canopy height and biomass at 1km spatial resolution.
2 Improving Shuttle Radar Topography Mission (SRTM) elevation dataset using ICESat's Geoscience Laser Altimeter System (GLAS).
3 High spatial resolution mapping of canopy height and biomass using polarimeteric synthetic aperture radar interferometry (polinSAR) and LiDAR.
4 Mapping of mangrove forests canopy height, biomass, productivity and assessment of vulnerability to anthropogenic activity and sea level change. +
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This comprehensive river discharge database covers the entire pan-Arctic drainage system. The collection comprises data from 9138 gauges and contains monthly river discharge data extending from the 1890s (for four Canadian and five Russian gauges) through the early 1990s, but the majority of data was collected between 1960 and 2001. The pan-Arctic drainage region covers a land area of approximately 21 million km2 and drains into the Arctic Ocean as well as Hudson Bay, James Bay, and the Northern Bering Strait. The collection also includes the Yukon and Anadyr River basins. Most of the drainage basins in the database are greater than 15,000 km2; however, the collection includes all available gauge data from Canada and Russia. Data from gauges measuring large drainage areas are of greatest interest to the regional, continental, and global-scale scientific community for modeling purposes. Individual station data are accessible through a graphical interface, or as tab-delimited ASCII text. Tab-delimited ASCII data are also compiled by hydrological region and as a single file for the complete data set. +
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This data portal, operated by the National Oceanic and Atmospheric Administration (NOAA) and the National Climatic Data Center (NCDC), contains archives of weather radar data (Doppler radar: NEXRAD), satellite coverage, and additional surface and marine data. These additional surface and marine data comprise historical forecasts and analyses, as well as the International Comprehensive Ocean-Atmosphere Data Set (ICOADS) that covers three centuries of global ocean-atmosphere data, including 2x2 and (since 1960) 1x1 degree gridded data sets.
A tutorial for retrieving radar data is here:
http://www.ncdc.noaa.gov/oa/radar/nxhastutorial.html +
S
This data set is generated from brightness temperature data derived from Nimbus-7 Scanning Multichannel Microwave Radiometer (SMMR) and Defense Meteorological Satellite Program (DMSP) -F8, -F11 and -F13 Special Sensor Microwave/Imager (SSM/I) radiances at a grid cell size of 25 x 25 km. The data are provided in the polar stereographic projection.
This product is designed to provide a consistent time series of sea ice concentrations (the fraction, or percentage, of ocean area covered by sea ice) spanning the coverage of several passive microwave instruments. To aid in this goal, sea ice algorithm coefficients are changed to reduce differences in sea ice extent and area as estimated using the SMMR and SSM/I sensors. The data are generated using the NASA Team algorithm developed by the Oceans and Ice Branch, Laboratory for Hydrospheric Processes at NASA Goddard Space Flight Center (GSFC).
These data include gridded daily (every other day for SMMR data) and monthly averaged sea ice concentrations for both the north and south polar regions. Two types of data are provided: final data and preliminary data. Final data are produced at GSFC about once per year, with roughly a one-year latency, and include data since 26 October 1978. Final data are produced from SMMR brightness temperature data processed at NASA GSFC and SSM/I brightness temperature data processed at the National Snow and Ice Data Center (NSIDC). Preliminary data are produced at NSIDC approximately every three months (quarterly), using SSM/I data acquired from Remote Sensing Systems, Inc. (RSS), and include roughly the most recent three to twelve months of processed data.
Data are scaled and stored as one-byte integers in flat binary arrays. +
C
This data set is related to the degradational sand-gravel laoratory experiment described in http://dx.doi.org/10.1002/2016WR018938. It was created by Clara Orru, Delft University of Technology. +
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This data set provides acoustic measurements of the bottom boundary layer in a tidal current over flat muddy-sand bed. Observations made with Nortek Vectrino Profiler over the lowest 2.5 cm of the water column with a 1 mm resolution. Observations were made in June of 2011 just after slack tide during a flood tidal flow. Please contact Diane Foster of the University of New Hampshire with any questions (diane.foster@unh.edu).
References:
Wengrove, M. E., & Foster, D. L. (2014). Field evidence of the viscous sublayer in a tidally forced developing boundary layer. Geophysical Research Letters, 41(14), 5084-5090.
Wengrove, M. E., Foster, D. L., Kalnejais, L. H., Percuoco, V., & Lippmann, T. C. (2015). Field and laboratory observations of bed stress and associated nutrient release in a tidal estuary. Estuarine, Coastal and Shelf Science, 161, 11-24. +
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This dataset consists of borehole temperature measurements acquired in permafrost regions of arctic Alaska between 1950 and 1988 by the U.S. Geological Survey. A large number of the 87 sites (boreholes) represented in this dataset are deep enough to penetrate the base of permafrost. +
N
This dataset includes observations of water level, water temperature, and wave field collected in 2009 and 2010 near Drew Point, AK by investigators Anderson, Overeem, and Wobus, with help from Adam LeWinter. This data was used in a publication published in 2014 by Barnhart et al.
Please see the file README.txt that accompanies the data files.
Barnhart, K. R., R. S. Anderson, I. Overeem, C. Wobus, G. D. Clow, and F. E. Urban (2014), Modeling erosion of ice-rich permafrost bluffs along the Alaskan Beaufort Sea coast, Journal of Geophysical Research Earth Surface, 119, doi:10.1002/2013JF002845.
Five files are included in this dataset:
1. README.txt (this document)
2. TidbitWaterTemperature_2009.txt
3. WaveLogger2_2009.txt
4. WaveLoggerTemperature_2009
5. Levelogger_2010.txt
6. WaveLogger_2010.txt +
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This dataset links human land use and land cover types from the Land-Use Harmonization (LUH2) dataset (Lawrence et al., 2016) to four hydrologic soil groups from 850 to 2015 derived from the SoilGrids250m soils dataset (Hengl et al., 2017). These groups represent sandy soils (hydrologic group A) consisting of texture classes sand, sandy-loam and loamy sand; silty soils (hydrologic group B) consisting of loam, silty-loam and silt; a mixed sand-silt-clay soils (hydrologic group C); and clayey soils (hydrologic group D) represented by clay, sandy-clay, clay-loam, silty-clay, and silt-clay-loam texture classes from the SoilGrids250m dataset. This dataset makes it possible to better link LULCs to soil types typically used for these activities potentially improving the simulation of water, energy and biogeochemical processes in Earth System Models. Additionally, it lays the foundation for simulating LULC impacts on soils that have different vulnerabilities and responses to human uses of soils. +
O
This project is developing a processing system and data center to provide operational ocean surface velocity fields from satellite altimeter and vector wind data.
The regional focus will be the tropical Pacific, where we will demonstrate the value for a variety of users, specifically fisheries management and recruitment, monitoring debris drift, larvae drift, oil spills, fronts and eddies, as well as on-going large scale ENSO monitoring, diagnostics and prediction. We will encourage additional uses in search and rescue, naval and maritime operations. The data will be subjected to extensive validation and error analysis, and applied to various ocean, climate and dynamic basic research problems. The user base derives from the NOAA CoastWatch and climate prediction programs, the broad research community, the Navy's operational ocean analysis program, and other civilian uses. The end product is to leave in place a turnkey system running at NOAA/NESDIS, with an established user clientele and easy internet data access.
The method to derive surface currents with satellite altimeter and scatterometer data is the outcome of several years NASA sponsored research.
The proposed project will transition that capability to operational oceanographic applications. The end product will be velocity maps updated daily, with a goal for eventual 2-day maximum delay from time of satellite measurement. Grid resolution will be 100 km for the basin scale, and finer resolution in the vicinity of the Pacific Islands. The team consists of private non-profit, educational and government partners with broad experience and familiarity with the data, and the scientific and technical issues. Two Partners are the original developers of the surface current derivation techniques, and two are closely tied to satellite data sources and primary processing centers. Others represent NOAA/NESDIS, Climate Prediction Center, CoastWatch, NMFS and the Navy to evaluate uses and applications.
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WAVEWATCH III™ (Tolman 1997, 1999a, 2009) is a third generation wave model developed at NOAA/NCEP in the spirit of the WAM model (WAMDIG 1988, Komen et al. 1994). It is a further development of the model WAVEWATCH, as developed at Delft University of Technology (Tolman 1989, 1991a) and WAVEWATCH II, developed at NASA, Goddard Space Flight Center (e.g., Tolman 1992). WAVEWATCH III™, however, differs from its predecessors in many important points such as the governing equations, the model structure, the numerical methods and the physical parameterizations. Furthermore, with model version 3.14, WAVEWATCH III™ is evolving from a wave model into a wave modeling framework, which allows for easy development of additional physical and numerical approaches to wave modeling.
WAVEWATCH III™ solves the random phase spectral action density balance equation for wavenumber-direction spectra. The implicit assumption of this equation is that properties of medium (water depth and current) as well as the wave field itself vary on time and space scales that are much larger than the variation scales of a single wave. With version 3.14 some source term options for extremely shallow water (surf zone) have been included, as well as wetting and drying of grid points. Whereas the surf-zone physics implemented so far are still fairly rudimentary, it does imply that the wave model can now be applied to arbitrary shallow water. +
A
We present data for use with ML, dealing with the sediment/rock substrates of the NE USA Continental Margin. The pointwise Labelled Data from seabed observations should be spatially extended over the entire area in an intelligent way. To aid that, environmental Feature Layers can be employed to train any chosen Machine Learning method. The trained ML model is then extended across all the vacant areas. The result predicts what the seabed is made of, so that survey operations (including research) can be planned, or biogeochemical budgets can be calculated. The idea of the Challenge Dataset is to permit people - researchers and students - to experiment with their own Machine Learning algorithms and data-preparation adjustments to achieve the BEST POSSIBLE mapping over the area. Metrics on the uncertainties should also be computed. For the time being the mappings are in terms of mud/sand/gravel, rock exposure, and carbonate and organic carbon contents. See the Powerpoint file in the Zipfile for further instructions. +
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World Ocean Atlas 2009 (WOA09) is a set of objectively analyzed (1° grid) climatological fields of in situ temperature, salinity, dissolved oxygen, Apparent Oxygen Utilization (AOU), percent oxygen saturation, phosphate, silicate, and nitrate at standard depth levels for annual, seasonal, and monthly compositing periods for the World Ocean. It also includes associated statistical fields of observed oceanographic profile data interpolated to standard depth levels on both 1° and 5° grids . +
U
World Population Prospects: The 2008 Revision Population Database from the United Nations Population Division.
The preparation of each new revision of the official population estimates and projections of the United Nations involves two distinct processes: (a) the incorporation of all new and relevant information regarding the past demographic dynamics of the population of each country or area of the world; and (b) the formulation of detailed assumptions about the future paths of fertility, mortality and international migration. The data sources used and the methods applied in revising past estimates of demographic indicators (i.e., those referring to 1950-2010) are presented online and in volume III of World Population Prospects: The 2008 Revision (forthcoming).
The future population of each country is projected starting with an estimated population for 1 July 2010. Because population data are not necessarily available for that date, the 2010 estimate is derived from the most recent population data available for each country, obtained usually from a population census or a population register, projected to 2010 using all available data on fertility, mortality and international migration trends between the reference date of the population data available and 1 July 2010. In cases where data on the components of population change relative to the past 5 or 10 years are not available, estimated demographic trends are projections based on the most recent available data. Population data from all sources are evaluated for completeness, accuracy and consistency, and adjusted as necessary.
To project the population until 2050, the United Nations Population Division uses assumptions regarding future trends in fertility, mortality and international migration. Because future trends cannot be known with certainty, a number of projection variants are produced. The following paragraphs summarize the main assumptions underlying the derivation of demographic indicators for the period starting in 2010 and ending in 2050. A more detailed description of the different assumptions will be available in volume III of World Population Prospects: The 2008 Revision (forthcoming)
The 2008 Revision includes eight projection variants. The eight variants are: low; medium; high; constant-fertility; instant-replacement-fertility; constant-mortality; no change (constant-fertility and constant-mortality); and zero-migration. The World Population Prospects Highlights focuses on the medium variant of the 2008 Revision, and results from the first four variants are available on-line.
