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A GIS, however, can be used to depict two- and three-dimensional characteristics of the Earth's surface, subsurface, and atmosphere from information points. For example, a GIS can quickly generate a map with isopleth or contour lines that indicate differing amounts of rainfall. Such a map can be thought of as a rainfall contour map.
Rain gauge for measuring liquid precipitation over a set period of time; Wind sock for measuring general wind speed and wind direction; Wind vane (also called a weather vane or a weathercock) for showing the wind direction; Present Weather/Precipitation Identification Sensor for identifying falling precipitation; Disdrometer for measuring drop ...
On the top right corner of the model for a surface weather map is the pressure, showing the last two integer digits of the pressure in millibars, or hectopascals, along with the first decimal. For instance, if the pressure at a certain location is 999.7 hPa, the pressure portion of the station model will read 997.
A weather map, also known as synoptic weather chart, displays various meteorological features across a particular area at a particular point in time and has various symbols which all have specific meanings. [1] Such maps have been in use since the mid-19th century and are used for research and weather forecasting purposes.
There are also many different types of geodata, including vector files, raster files, geographic databases, web files, and multi-temporal data. Spatial data or spatial information is broader class of data whose geometry is relevant but it is not necessarily georeferenced , such as in computer-aided design (CAD), see geometric modeling .
The 20th century developed new remote sensing tools, such as weather radars, weather satellites and wind profilers, which provide better sampling both regionally and globally. Remote sensing instruments collect data from weather events some distance from the instrument and typically stores the data where the instrument is located and often ...
Most geographic information systems (GIS) and GIS libraries use EPSG codes as Spatial Reference System Identifiers (SRIDs) and EPSG definition data for identifying coordinate reference systems, projections, and performing transformations between these systems, while some also support SRIDs issued by other organizations (such as Esri).
The study of GIR systems has a rich history dating back to the 1970s and possibly earlier. See Ray Larson’s book Geographic information retrieval and spatial browsing [20] for references to much of the pre-Web literature on GIR. In 2005 the Cross-Language Evaluation Forum added a geographic track, GeoCLEF.