{"id":325,"date":"2015-09-14T18:08:06","date_gmt":"2015-09-14T18:08:06","guid":{"rendered":"https:\/\/courses.candelalearning.com\/geophysical\/?post_type=chapter&p=325"},"modified":"2017-04-19T21:47:34","modified_gmt":"2017-04-19T21:47:34","slug":"geospatial-technology","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-geophysical\/chapter\/geospatial-technology\/","title":{"raw":"Geospatial Technology","rendered":"Geospatial Technology"},"content":{"raw":"Data, data, data .\u00a0.\u00a0.\u00a0data\u00a0is everywhere. It\u2019s collected every time you go to the grocery store and use\u00a0their card to reduce the costs, when you click on a link on Facebook, or when\u00a0you do any kind of search on a search engine like Google, Bing, or Yahoo!. It is\u00a0used by your state department of transportation when you are driving on a\u00a0freeway or when you use an app on a smart phone. Futurists believe that in the\u00a0near future, face recognition technology will allow a sales representative know\u00a0what types of clothes you like to buy based on a database of your recent\u00a0purchases at their store and others.\u00a0Now there are two basic types of data you need to know: spatial\u00a0and non-spatial data. Spatial data<\/strong>,\u00a0also called geospatial data<\/strong>, is\u00a0data that can be linked to a specific location on Earth. Geospatial data is\u00a0becoming \u201cbig business\u201d because it isn\u2019t just data, but data that can be\u00a0located, tracked, patterned, and modeled based on other geospatial data. Census\u00a0information that is collected every 10 years is an example of spatial data.\u00a0Non-spatial\u00a0data<\/strong> is data that cannot be specifically traced to a specific location.\u00a0This might include the number of people living in a household, enrollment within\u00a0a specific course, or gender information. But non-spatial data can easily become\u00a0spatial data if it can be linked in some way to a location. Geospatial\u00a0technology specialists have a method called geocoding<\/strong>\u00a0that can be used to give non-spatial data a geographic location. Once data has a\u00a0spatial component associated with it, the type of questions that can be asked\u00a0dramatically changes.\r\n

Remote Sensing<\/h2>\r\n\"Artist's\r\n\r\nRemote\u00a0sensing<\/strong>\u00a0can\u00a0be defined as human\u2019s ability to study objects without being in direct physical\u00a0contact with them. So for example, your eyes are a form of\u00a0passive\u00a0remote sensing<\/em>\u00a0because they are\u00a0\u201cpassively\u201d\u00a0absorbing\u00a0electromagnetic energy within the visible spectrum from distant objects\u00a0and your\u00a0brain is processing that energy into information. There\u00a0are\u00a0a variety of remote\u00a0sensing platforms or devices, but they can basically be categorized into the\u00a0following that we will look at throughout the\u00a0course.\u00a0Satellite imagery<\/strong>\u00a0is a type of remotely sensed imagery taken of the Earth's surface, which is produced from orbiting satellites that gather data via electromagnetic energy. Next is\u00a0areal photography<\/strong>, which is\u00a0film-based or digital photographs of the Earth, usually from an airplane or non-piloted drone. Images are either taken from a vertical\u00a0or oblique position.\u00a0Third is\u00a0radar<\/strong>, which is an interesting form of remote sensing technology that uses microwave pulses\u00a0to create imagery of features on Earth. This can be from a satellite image or\u00a0ground-based\u00a0Doppler\u00a0radar for weather\u00a0forecasting.\u00a0Finally, a fast growing realm of remote sensing is called\u00a0Light Detection and Ranging<\/strong>\u00a0or\u00a0Lidar<\/strong>, which\u00a0is a form of remote sensing that measures distance of objects using laser pulses of light.\r\n\r\n\"Title:\r\n

Global Positioning Systems<\/h2>\r\nAnother type of\u00a0geospatial technology is global positioning systems (GPS) and a key technology for acquiring accurate control points on Earth\u2019s surface. Now to determine the location of that GPS receiver on\u00a0Earth\u2019s surface, a minimum of four satellites are required using a mathematical\u00a0process called\u00a0triangulation<\/strong>. Normally the process of triangulation\u00a0requires a minimum of three transmitters, but because the energy sent from the satellite is traveling at the speed of light, minor errors in calculation could\u00a0result in large location errors on the ground. Thus, a minimum of four satellites is often used to reduce this error. This process using the geometry\u00a0of triangles to determine location is used not only in GPS, but a variety of other location needs like finding the epicenter of earthquakes.A\u00a0user can use a GPS receiver to determine their location on Earth through a dynamic conversation with satellites in space. Each satellite transmits orbital\u00a0information called the\u00a0ephemeris<\/strong>\u00a0using a highly accurate atomic\u00a0clock along with its orbital position called the\u00a0almanac<\/strong>. The\u00a0receiver will use this information to determine its distance from a single\u00a0satellite using the equation D<\/em>\u00a0=\u00a0rt<\/em>, where D<\/em> = distance, r<\/em> = rate or the speed\u00a0of light (299,792,458 meters per second), and t<\/em> = time using the atomic clock.\u00a0The atomic clock is required because the receiver is trying to calculate\u00a0distance, using energy that is transmitted at the speed of light. Time will be\u00a0fractions of a second and requires a \u201ctime clock\u201d up the upmost\u00a0accuracy.\r\n\r\n\"Satellite\r\n\r\nThere is a technology that\u00a0exists that can bring together remote sensing data, GPS data points, spatial and\u00a0non-spatial data, and spatial statistics into a single, dynamic system for\u00a0analysis and that is a\u00a0geographic information system<\/strong>\u00a0(GIS). A\u00a0GIS is a powerful database system that allows users to acquire, organize, store,\u00a0and most importantly analyze information about the physical and cultural\u00a0environments. A GIS views the world as overlaying physical or cultural layers,\u00a0each with quantifiable data that can be analyzed. A single GIS map of a\u00a0national forest could have layers such as elevation, deciduous trees,\u00a0evergreens, soil type, soil erosion rates, rivers and tributaries, major and\u00a0minor roads, forest health, burn areas, regrowth, restoration, animal species\u00a0type, trails, and more. Each of these layers would contain a database of\u00a0information specific to that\u00a0layer.Nearly every discipline,\u00a0career path, or academic pursuit uses geographic information systems because of\u00a0the vast amount of data and information about the physical and cultural world.\u00a0Disciplines and career paths that use GIS include: conservation, ecology,\u00a0disaster response and mitigation, business, marketing, engineering, sociology,\u00a0demography, astronomy, transportation, health, criminal justice and law\u00a0enforcement, travel and tourism, news media, and the list could endlessly go\u00a0on.Now, GIS primarily works from\u00a0two different spatial models: raster and vector.\u00a0Raster<\/strong>\u00a0based GIS models are images much like a\u00a0digital picture. Each image is broken down into a series of columns and rows of\u00a0pixels and each pixel is\u00a0georeferenced<\/strong>\u00a0to somewhere on Earth's surface\u00a0is represents\u00a0a specific numeric value\u2014usually a specific color or wavelength\u00a0within the\u00a0electromagnetic spectrum<\/strong>.\u00a0Most remote sensing images come into a GIS as a raster\u00a0layer. The other type of GIS model is called a vector model.\u00a0Vector<\/strong>\u00a0based GIS models are based on the concept of points that are again georeferenced\u00a0(i.e. given an x-, y<\/em>-, and possibly z<\/em>-location) to somewhere specific on the\u00a0ground. From points, lines can be created by connecting a series of points and\u00a0areas can be created by closing loops of vector lines. For each of these vector layers, a database of information can be attributed to it. So for example, a\u00a0vector line of rivers could have a database associated with it such as length,\u00a0width, stream flow, government agencies responsible for it, and anything else\u00a0the GIS user wants tied to it. What these vector models represent is also a\u00a0matter of\u00a0scale<\/strong>. For example, a city can be represented as a point or a\u00a0polygon depending on how zoomed in you are to the location. A map of the world\u00a0would show cities as points, whereas a map of a single county may show the city\u00a0as a polygon with roads, populations, pipes, or grid systems within\u00a0it.\r\n\r\nhttps:\/\/youtu.be\/Sj7nSRlWHU8","rendered":"

Data, data, data .\u00a0.\u00a0.\u00a0data\u00a0is everywhere. It\u2019s collected every time you go to the grocery store and use\u00a0their card to reduce the costs, when you click on a link on Facebook, or when\u00a0you do any kind of search on a search engine like Google, Bing, or Yahoo!. It is\u00a0used by your state department of transportation when you are driving on a\u00a0freeway or when you use an app on a smart phone. Futurists believe that in the\u00a0near future, face recognition technology will allow a sales representative know\u00a0what types of clothes you like to buy based on a database of your recent\u00a0purchases at their store and others.\u00a0Now there are two basic types of data you need to know: spatial\u00a0and non-spatial data. Spatial data<\/strong>,\u00a0also called geospatial data<\/strong>, is\u00a0data that can be linked to a specific location on Earth. Geospatial data is\u00a0becoming \u201cbig business\u201d because it isn\u2019t just data, but data that can be\u00a0located, tracked, patterned, and modeled based on other geospatial data. Census\u00a0information that is collected every 10 years is an example of spatial data.\u00a0Non-spatial\u00a0data<\/strong> is data that cannot be specifically traced to a specific location.\u00a0This might include the number of people living in a household, enrollment within\u00a0a specific course, or gender information. But non-spatial data can easily become\u00a0spatial data if it can be linked in some way to a location. Geospatial\u00a0technology specialists have a method called geocoding<\/strong>\u00a0that can be used to give non-spatial data a geographic location. Once data has a\u00a0spatial component associated with it, the type of questions that can be asked\u00a0dramatically changes.<\/p>\n

Remote Sensing<\/h2>\n

\"Artist's<\/p>\n

Remote\u00a0sensing<\/strong>\u00a0can\u00a0be defined as human\u2019s ability to study objects without being in direct physical\u00a0contact with them. So for example, your eyes are a form of\u00a0passive\u00a0remote sensing<\/em>\u00a0because they are\u00a0\u201cpassively\u201d\u00a0absorbing\u00a0electromagnetic energy within the visible spectrum from distant objects\u00a0and your\u00a0brain is processing that energy into information. There\u00a0are\u00a0a variety of remote\u00a0sensing platforms or devices, but they can basically be categorized into the\u00a0following that we will look at throughout the\u00a0course.\u00a0Satellite imagery<\/strong>\u00a0is a type of remotely sensed imagery taken of the Earth’s surface, which is produced from orbiting satellites that gather data via electromagnetic energy. Next is\u00a0areal photography<\/strong>, which is\u00a0film-based or digital photographs of the Earth, usually from an airplane or non-piloted drone. Images are either taken from a vertical\u00a0or oblique position.\u00a0Third is\u00a0radar<\/strong>, which is an interesting form of remote sensing technology that uses microwave pulses\u00a0to create imagery of features on Earth. This can be from a satellite image or\u00a0ground-based\u00a0Doppler\u00a0radar for weather\u00a0forecasting.\u00a0Finally, a fast growing realm of remote sensing is called\u00a0Light Detection and Ranging<\/strong>\u00a0or\u00a0Lidar<\/strong>, which\u00a0is a form of remote sensing that measures distance of objects using laser pulses of light.<\/p>\n

\"Title:<\/p>\n

Global Positioning Systems<\/h2>\n

Another type of\u00a0geospatial technology is global positioning systems (GPS) and a key technology for acquiring accurate control points on Earth\u2019s surface. Now to determine the location of that GPS receiver on\u00a0Earth\u2019s surface, a minimum of four satellites are required using a mathematical\u00a0process called\u00a0triangulation<\/strong>. Normally the process of triangulation\u00a0requires a minimum of three transmitters, but because the energy sent from the satellite is traveling at the speed of light, minor errors in calculation could\u00a0result in large location errors on the ground. Thus, a minimum of four satellites is often used to reduce this error. This process using the geometry\u00a0of triangles to determine location is used not only in GPS, but a variety of other location needs like finding the epicenter of earthquakes.A\u00a0user can use a GPS receiver to determine their location on Earth through a dynamic conversation with satellites in space. Each satellite transmits orbital\u00a0information called the\u00a0ephemeris<\/strong>\u00a0using a highly accurate atomic\u00a0clock along with its orbital position called the\u00a0almanac<\/strong>. The\u00a0receiver will use this information to determine its distance from a single\u00a0satellite using the equation D<\/em>\u00a0=\u00a0rt<\/em>, where D<\/em> = distance, r<\/em> = rate or the speed\u00a0of light (299,792,458 meters per second), and t<\/em> = time using the atomic clock.\u00a0The atomic clock is required because the receiver is trying to calculate\u00a0distance, using energy that is transmitted at the speed of light. Time will be\u00a0fractions of a second and requires a \u201ctime clock\u201d up the upmost\u00a0accuracy.<\/p>\n

\"Satellite<\/p>\n

There is a technology that\u00a0exists that can bring together remote sensing data, GPS data points, spatial and\u00a0non-spatial data, and spatial statistics into a single, dynamic system for\u00a0analysis and that is a\u00a0geographic information system<\/strong>\u00a0(GIS). A\u00a0GIS is a powerful database system that allows users to acquire, organize, store,\u00a0and most importantly analyze information about the physical and cultural\u00a0environments. A GIS views the world as overlaying physical or cultural layers,\u00a0each with quantifiable data that can be analyzed. A single GIS map of a\u00a0national forest could have layers such as elevation, deciduous trees,\u00a0evergreens, soil type, soil erosion rates, rivers and tributaries, major and\u00a0minor roads, forest health, burn areas, regrowth, restoration, animal species\u00a0type, trails, and more. Each of these layers would contain a database of\u00a0information specific to that\u00a0layer.Nearly every discipline,\u00a0career path, or academic pursuit uses geographic information systems because of\u00a0the vast amount of data and information about the physical and cultural world.\u00a0Disciplines and career paths that use GIS include: conservation, ecology,\u00a0disaster response and mitigation, business, marketing, engineering, sociology,\u00a0demography, astronomy, transportation, health, criminal justice and law\u00a0enforcement, travel and tourism, news media, and the list could endlessly go\u00a0on.Now, GIS primarily works from\u00a0two different spatial models: raster and vector.\u00a0Raster<\/strong>\u00a0based GIS models are images much like a\u00a0digital picture. Each image is broken down into a series of columns and rows of\u00a0pixels and each pixel is\u00a0georeferenced<\/strong>\u00a0to somewhere on Earth’s surface\u00a0is represents\u00a0a specific numeric value\u2014usually a specific color or wavelength\u00a0within the\u00a0electromagnetic spectrum<\/strong>.\u00a0Most remote sensing images come into a GIS as a raster\u00a0layer. The other type of GIS model is called a vector model.\u00a0Vector<\/strong>\u00a0based GIS models are based on the concept of points that are again georeferenced\u00a0(i.e. given an x-, y<\/em>-, and possibly z<\/em>-location) to somewhere specific on the\u00a0ground. From points, lines can be created by connecting a series of points and\u00a0areas can be created by closing loops of vector lines. For each of these vector layers, a database of information can be attributed to it. So for example, a\u00a0vector line of rivers could have a database associated with it such as length,\u00a0width, stream flow, government agencies responsible for it, and anything else\u00a0the GIS user wants tied to it. What these vector models represent is also a\u00a0matter of\u00a0scale<\/strong>. For example, a city can be represented as a point or a\u00a0polygon depending on how zoomed in you are to the location. A map of the world\u00a0would show cities as points, whereas a map of a single county may show the city\u00a0as a polygon with roads, populations, pipes, or grid systems within\u00a0it.<\/p>\n