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National Lidar Dataset
A national lidar dataset refers to a high-resolution lidar dataset comprising most—and ideally all—of a nation’s terrain. Datasets of this type typically meet specified quality standards and are publicly available for free (or at nominal cost) in one or more uniform formats from government or academic sources. National LiDAR datasets are used primarily in topographic mapping, and also for forestry, urban and rural planning, recreational, environmental, engineering, and geological studies and planning, among others. Countries with national lidar datasets either completed or in progress include: {, class="wikitable" style="text-align:center" , - ! Country ! Dataset Status ! Resolution (pts/m2) ! Source ! Additional Information , - , Canada , Montréal completed, 2015 , 10 , , - , Denmark , Completed, 2008, 2013 , 4 , Pointspacing is from 4/ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lidar
Lidar (, also LIDAR, or LiDAR; sometimes LADAR) is a method for determining ranges (variable distance) by targeting an object or a surface with a laser and measuring the time for the reflected light to return to the receiver. It can also be used to make digital 3-D representations of areas on the Earth's surface and ocean bottom of the intertidal and near coastal zone by varying the wavelength of light. It has terrestrial, airborne, and mobile applications. ''Lidar'' is an acronym of "light detection and ranging" or "laser imaging, detection, and ranging". It is sometimes called 3-D laser scanning, a special combination of 3-D scanning and laser scanning. Lidar is commonly used to make high-resolution maps, with applications in surveying, geodesy, geomatics, archaeology, geography, geology, geomorphology, seismology, forestry, atmospheric physics, laser guidance, airborne laser swath mapping (ALSM), and laser altimetry. It is also used in control and navigation for som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topographic Mapping
In modern mapping, a topographic map or topographic sheet is a type of map characterized by large- scale detail and quantitative representation of relief features, usually using contour lines (connecting points of equal elevation), but historically using a variety of methods. Traditional definitions require a topographic map to show both natural and artificial features. A topographic survey is typically based upon a systematic observation and published as a map series, made up of two or more map sheets that combine to form the whole map. A topographic map series uses a common specification that includes the range of cartographic symbols employed, as well as a standard geodetic framework that defines the map projection, coordinate system, ellipsoid and geodetic datum. Official topographic maps also adopt a national grid referencing system. Natural Resources Canada provides this description of topographic maps: Other authors define topographic maps by contrasting them with anothe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slovenian Environment Agency
The Slovenian Environment Agency (Slovenian: ''Agencija Republike Slovenije za okolje'' or ''ARSO'') is the main organisation for environment of the Republic of Slovenia. It was established in 2001 with a reorganisation of the ''Hydrometeorological Institute of Slovenia''. Since 2012, it is part of the Ministry of Agriculture and the Environment; before, it was part of the Ministry of the Environment and Spatial Planning. , its director general is Silvo Žlebir. The range of duties of this organisation are in the field of monitoring, analysing and forecasting of natural phenomena and processes in the environment and reduction of the danger to people and their property as follows: * national service for meteorology * national service for hydrology * national service for seismology * monitoring of the pollution of the environment and the provision of quality public environmental data * exercise the requirements for the protection of the environment, which result from forcing regulation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National LIDAR Dataset - USA
Currently, the best source for nationwide LiDAR availability from public sources is the United States Interagency Elevation Inventory (USIEI). The USIEI is a collaborative effort of NOAA and the U.S. Geological Survey, with contributions from the Federal Emergency Management Agency, the Natural Resources Conservation Service, the US Army Corps of Engineers, and the National Park Service. The inventory displays high-accuracy topographic and bathymetric data for the US, and it's intended to be a comprehensive, nationwide listing of known high-accuracy topographic data, including lidar. The inventory is updated semi-annually. Note, however, that getting access to the data is often less than straightforward in the current implementation. History: In the United States, the United States Geological Survey (USGS) was the lead agency coordinating efforts across multiple agencies towards a National LIDAR Dataset. The first meeting, a National LIDAR Initiative Strategy Meeting, was held at USG ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Elevation Model
A digital elevation model (DEM) or digital surface model (DSM) is a 3D computer graphics representation of elevation data to represent terrain or overlaying objects, commonly of a planet, moon, or asteroid. A "global DEM" refers to a discrete global grid. DEMs are used often in geographic information systems (GIS), and are the most common basis for digitally produced relief maps. A digital terrain model (DTM) represents specifically the ground surface while DEM and DSM may represent tree top canopy or building roofs. While a DSM may be useful for landscape modeling, city modeling and visualization applications, a DTM is often required for flood or drainage modeling, land-use studies, geological applications, and other applications, and in planetary science. Terminology There is no universal usage of the terms ''digital elevation model'' (DEM), ''digital terrain model'' (DTM) and ''digital surface model'' (DSM) in scientific literature. In most cases the term ''digital ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Elevation Dataset
The National Elevation Dataset (NED) consists of high precision topography or ground surface elevation data (digital elevation model) for the United States. It was maintained by the USGS and all the data is in the public domain. Since the 3D Elevation Program came online, the NED was subsumedThe National Map elevation informati/ref> into The National Map as one of its layers of information. Sources The NED dataset is a compilation of data from a variety of existing high-precision datasets such as LiDAR data (see also National LIDAR Dataset - USA), contour maps, USGS DEM collection, SRTM and other sources which were reorganized and combined into a seamless dataset, designed to cover all the United States territory in its continuity. Formats Data is available in a few popular formats such as ESRI ArcGRID, GeoTIFF, BIL, GridFloat, and a few others. Precision Depending on area location, the datasets are provided with 1/9 (about 3 meters), 1/3 (about 10 m) and 1-arcsecond A m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Remote Sensing
Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Earth and other planets. Remote sensing is used in numerous fields, including geography, land surveying and most Earth science disciplines (e.g. hydrology, ecology, meteorology, oceanography, glaciology, geology); it also has military, intelligence, commercial, economic, planning, and humanitarian applications, among others. In current usage, the term ''remote sensing'' generally refers to the use of satellite- or aircraft-based sensor technologies to detect and classify objects on Earth. It includes the surface and the atmosphere and oceans, based on propagated signals (e.g. electromagnetic radiation). It may be split into "active" remote sensing (when a signal is emitted by a satellite or aircraft to the object and its reflection detected by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Topography
Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary science and is concerned with local detail in general, including not only relief, but also natural, artificial, and cultural features such as roads, land boundaries, and buildings. In the United States, topography often means specifically ''relief'', even though the USGS topographic maps record not just elevation contours, but also roads, populated places, structures, land boundaries, and so on. Topography in a narrow sense involves the recording of relief or terrain, the three-dimensional quality of the surface, and the identification of specific landforms; this is also known as geomorphometry. In modern usage, this involves generation of elevation data in digital form (DEM). It is often considered to include the graphic representation of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geographic Data And Information By Country
Geography (from Greek: , ''geographia''. Combination of Greek words ‘Geo’ (The Earth) and ‘Graphien’ (to describe), literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, and phenomena of Earth. The first recorded use of the word γεωγραφία was as a title of a book by Greek scholar Eratosthenes (276–194 BC). Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not merely where objects are, but also how they have changed and come to be. While geography is specific to Earth, many concepts can be applied more broadly to other celestial bodies in the field of planetary science. One such concept, the first law of geography, proposed by Waldo Tobler, is "everything is related to everything else, but near things are more related than distant things." Geography has been called "the world discipline" and "the bridge between the human and th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
