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Core Areas of Geospatial Intelligence

Over the past several decades, the missions of agencies now represented in the National Geospatial-Intelligence Agency (NGA) have intersected with several academic fields, including geodesy, geophysics, cartographic science, geographic information science and spatial analysis, photogrammetry, and remote sensing. Advanced work in these fields depends on university research and curricula, the supply of graduate students, and technological advances. Agencies frequently sent employees to universities to gain specific expertise, for example to Ohio State University for geodesy (Cloud, 2000).

In recent years, many of these academic fields have become increasingly interdisciplinary and interrelated. For example, digital photogrammetry has so changed the field that its methods are barely distinguishable from remote sensing. Similarly, new labels such as geomatics have emerged, reflecting the overlap among surveying, photogrammetry, and geodesy. Few academic programs treat geographic information science, spatial analysis, and cartography as separate fields of study, but usually regard them as tracks or emphases within geography or another discipline. Professional organizations and academic journals reflect the interdisciplinary changes under way today. For example, mergers, name changes, and increasing overlap have characterized the professional organizations over the last decades (e.g., Ondrejka, 1997). This chapter examines how each of the core areas has evolved over time, the key concepts and methods that are currently taught, and the scope of existing education and professional preparation programs.

GEODESY AND GEOPHYSICS

Geodesy is the science of mathematically determining the size, shape, and orientation of the Earth and the nature of its gravity field in space over time. It includes the study of the Earth’s motions in space, the establishment of spatial reference frames, the science and engineering of high-accuracy, high-precision positioning, and the monitoring of dynamic Earth phenomena, such as ground movements and changes in sea-level rise and ice sheets. Because much of contemporary geodesy makes use of satellite technology, such as the Global Positioning System (GPS), topics such as orbital mechanics and transatmospheric radio wave and light propagation also fall within its purview. Geophysics comprises a broad range of subdisciplines, including geodesy, geomagnetism and paleomagnetism, atmospheric science, hydrology, seismology, space physics and aeronomy, tectonophysics, and some ocean science. Given NGA’s historical focus on geodesy, the following discussion concentrates on geodesy, touching on other subdisciplines of geophysics where appropriate.

Evolution

Geodesy is one of the oldest sciences whose study goes back to the ancient Greeks (e.g., Vaníček and Krakiwsky, 1986; Torge and Müller, 2012). The first attempt to accurately measure the Earth’s size was made in the third century B.C. By measuring the lengths of shadows, Eratosthenes of Cyrene determined the Earth’s circumference with an accuracy that would not be improved until the 17th century. The assumption



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2 Core Areas of Geospatial Intelligence O ver the past several decades, the missions of GEODESY AND GEOPHYSICS agencies now represented in the National Geospatial-Intelligence Agency (NGA) have Geodesy is the science of mathematically deter- intersected with several academic fields, including mining the size, shape, and orientation of the Earth geodesy, geophysics, cartographic science, geographic and the nature of its gravity field in space over time. information science and spatial analysis, photogram- It includes the study of the Earth’s motions in space, metry, and remote sensing. Advanced work in these the establishment of spatial reference frames, the sci- fields depends on university research and curricula, ence and engineering of high-accuracy, high-precision the supply of graduate students, and technological positioning, and the monitoring of dynamic Earth advances. Agencies frequently sent employees to uni- phenomena, such as ground movements and changes versities to gain specific expertise, for example to Ohio in sea-level rise and ice sheets. Because much of con- State University for geodesy (Cloud, 2000). temporary geodesy makes use of satellite technology, In recent years, many of these academic fields have such as the Global Positioning System (GPS), topics become increasingly interdisciplinary and interrelated. such as orbital mechanics and transatmospheric radio For example, digital photogrammetry has so changed wave and light propagation also fall within its purview. the field that its methods are barely distinguishable Geo­ hysics comprises a broad range of subdisciplines, p from remote sensing. Similarly, new labels such as geo- including geodesy, geomagnetism and paleo­magnetism, matics have emerged, reflecting the overlap among sur- atmospheric science, hydrology, seismology, space veying, photogrammetry, and geodesy. Few academic physics and aeronomy, tectonophysics, and some ocean programs treat geographic information science, spatial science. Given NGA’s historical focus on geodesy, the analysis, and cartography as separate fields of study, following discussion concentrates on geodesy, touching but usually regard them as tracks or emphases within on other subdisciplines of geophysics where appropriate. geography or another discipline. Professional organiza- tions and academic journals reflect the interdisciplinary Evolution changes under way today. For example, mergers, name changes, and increasing overlap have characterized the Geodesy is one of the oldest sciences whose study professional organizations over the last decades (e.g., goes back to the ancient Greeks (e.g., Vaníček and Ondrejka, 1997). This chapter examines how each of Krakiwsky, 1986; Torge and Müller, 2012). The first the core areas has evolved over time, the key concepts attempt to accurately measure the Earth’s size was made and methods that are currently taught, and the scope in the third century B.C. By measuring the lengths of existing education and professional preparation of shadows, Eratosthenes of Cyrene determined the programs. Earth’s circumference with an accuracy that would not be improved until the 17th century. The assumption 17

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18 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE that the Earth was a sphere was dispelled by Sir Isaac systems. New generations of GPS satellites are being Newton. In the first edition of Principia, published in deployed by the United States and several countries are 1687, Newton postulated that the Earth was slightly developing global navigation satellite systems (GNSS), ellipsoidal in shape, with the polar radius about 27 kilo- including the European Galileo, Chinese Compass, meters shorter than the equatorial radius. Refinements and Russian GLONASS systems. The use of GPS in field geodesy techniques slowly increased the accu- has become ubiquitous, with myriad civil and military racy of these estimates, but it was not until the dawn applications. Improvements on the horizon include of the space age that knowledge of the Earth’s size and the development of less expensive and more accurate shape improved significantly. Through the analysis of gravity gradiometry for determining the fine structure perturbations of satellite orbits, scientists first refined of the local gravity field and more accurate atomic the ellipsoidal dimensions of the Earth and then dis- clocks for measuring gravity and determining heights covered that the shape of the Earth, as represented by in the field.1 its gravity field, was much more complicated. An important advance in geophysics that is rel- When geodesists talk about the shape of the Earth, evant to NGA is the improvement in describing the what they actually mean is the shape of the equipo- Earth’s ever-changing magnetic field. The National tential surfaces of its gravity field. The equipotential Geophysical Data Center’s NGDC-720 model—­ surface that most closely approximates mean sea level compiled from satellite, ocean, aerial, and ground is called the geoid. One of the major tasks of geodesy is magnetic surveys—provides information on the field to map the geoid as accurately as possible. An example generated by magnetized rocks in the crust and upper of a highly accurate and precise geoid constructed using ­ mantle (Figure 2.2; Maus, 2010). This model is the first data from the Gravity field and steady-state Ocean step toward producing a geomagnetic field model that Circulation Explorer (GOCE) satellite is shown in would be useful for navigation. Figure 2.1 (Schiermeier, 2010; Floberghagen et al., 2011). Maps of the geoid provide information about Knowledge and Skills the structure of the Earth’s crust and upper mantle, plate tectonics, and sea-level change. The geoid is Graduate study in geodesy encompasses the theory needed to accurately determine satellite orbits and the and modern practice of geodesy. Topics include the use trajectories of ballistic missiles. It also finds everyday of mathematical tools such as least-squares adjustment, use as the surface from which orthometric heights, Kalman filtering, and spectral analysis; the principles the heights usually found on topographic maps, are of gravity field theory and orbital mechanics; the measured. Improved knowledge of the gravity field can propagation of electromagnetic waves; and the theory also be combined with GPS and/or inertial navigation and operation of observing instruments such as GNSS sensors to produce a more accurate navigation system receivers and inertial navigation systems. Modeling than can be provided by GPS alone. of observations to extract quantities of interest is a NGA’s ongoing needs for geodesy stem primarily key technique learned by students. While course-only from work carried out by the former Defense Mapping master’s degrees are available at some universities, Agency and include accurately and precisely determin- most graduate degrees in geodesy require completion ing the geoid, establishing accurate and precise coordi- of a research project, some of which involve substantial nate systems (datums) and positions within them (e.g., amounts of computer programming. Graduates may World Geodetic System 1984; Merrigan et al., 2002), carry out or manage research, and traditionally have a and relating different internationally used datums. In master’s or doctorate degree from a university specializ- particular, NGA is responsible for supporting Depart- ing in geodesy and an undergraduate degree in a related ment of Defense navigation systems, maintaining GPS field such as survey science, civil engineering, survey- fixed-site operations, and generating and distributing GPS precise ephemerides (Wiley et al., 2006). Advances in geodesy are driven largely by continu- 1Presentation by D. Smith, NOAA, to the NRC Workshop on ing improvements to and expansion of space geodetic New Research Directions for NGA, Washington, D.C., May 17-19, 2010.

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 19 FIGURE 2.1  The Gravity field and steady-state Ocean Circulation Explorer mission has produced one of the most accurate geoid models to date. The deviations in height (–100 m to +100 m) from an ellipsoid are exaggerated 10,000 times in the image. The blue colors represent low values and the reds/yellows represent high values. SOURCE: ESA/HPF/DLR. ing engineering, physics, astronomy, mathe­ atics, or m analysis), geodetic coordinate systems and datums, the computer science. elements of the Earth’s gravity field, and the basics of The knowledge taught at the undergraduate level geodetic positioning techniques such as high-precision is similar in breadth, but less in depth than that taught GPS surveying. Students should be well versed in at the graduate level. Courses include specialized the mathematical and physical principles underlying mathematics such as adjustment calculus (least-squares g ­ eodesy so that during their careers they can readily

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20 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE FIGURE 2.2  The downward-direction component of the crustal magnetic field, in nanoteslas, from the NGDC-720 model. The figure shows the magnetic potential, represented by spherical harmonic degree 16 to 720, which corresponds to the waveband of 2500 km to 56 km. SOURCE: National Geophysical Data Center. adapt to advances in the field. Graduates with an un- Education and Professional Preparation Programs dergraduate degree with geodesy as a major component commonly work as geodetic or surveying engineers, At the undergraduate level, geodesy is primarily who design and supervise data collection activities, taught in geomatics programs (Box 2.1), typically in carry out routine analyses, and solve small problems of a geomatics or surveying engineering department or a theoretical nature. as an option in a civil engineering department, and A bachelor’s degree in geophysics combines ­ tudies s sometimes in other departments (e.g., earth science, in geology and physics with mathematical training. ­ aerospace engineering, forestry). A few geography Graduates commonly work as exploration ­ eophysicists g programs teach geomatics, but there is typically little who prospect for oil, gas, or minerals; or as environ­ geodesy content. mental geophysicists who assess soil and rock prop- Only a handful of undergraduate geomatics pro- erties for various applications. A graduate degree in grams (e.g., University of Florida, Texas A&M Uni- g ­ eophysics, preferably a doctorate, is required for re- versity, Corpus Christi) currently exist in the United search. Graduate-level knowledge and skills acquired in States. More existed in the past2 but were terminated geophysics programs mirrors that in geodesy programs, because of reduced demand or a change in institutional with some overlap in subject areas. Additional topics of priorities. In some cases, the associated graduate pro- study include seismology and the structure and evolution gram survived. At the graduate level, geodesy is taught of the Earth, including plate tectonics, the theory and in geomatics, geophysics, earth science, planetary measurement of the Earth’s magnetic field, and space physics, including the nature of the ionosphere and 2 In the late 1970s, 13 schools in the United States offered 4-year magnetosphere and the phenomena of space weather bachelor’s programs in surveying or geodetic science, 8 offered a and its impact on modern technological systems. master’s degree in surveying, and 6 offered a Ph.D. in surveying and/or geodesy (NRC, 1978).

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 21 departments of physics, earth and planetary sciences, BOX 2.1 and geology and geophysics (e.g., Stanford University, Geomatics Harvard University; see Table A.1 in Appendix A). Many universities also offer master’s and doctorate Geodesy provides the scientific underpinning for geomatics, a relatively new term used to describe the science, engineering, and degree programs in geophysics, including the Cali- art involved in collecting and managing geographically referenced fornia Institute of Technology and the Massachusetts information. A number of government agencies, private companies, Institute of Technology. and academic institutions have embraced this term as a replacement for “surveying and mapping,” which no longer adequately describes the full spectrum of position-related tasks carried out by profes­ PHOTOGRAMMETRY sionals in the field. Geomatics covers activities ranging from the acquisition and analysis of site-specific spatial data in engineering The term photogrammetry is derived from three and development surveys to cadastral and hydrographic surveying Greek words: photos or light; gramma, meaning to the application of GIS and remote sensing technologies in envi­ something drawn or written; and metron or to mea- ronmental and land use management. sure. ­ ogether the words mean to measure graphi- T cally by means of light. Photogrammetry is concerned with observing and measuring physical objects and p ­ henomena from a medium such as film (Mikhail et al., science, or engineering (primarily instrumentation- 2001). Whereas photographs were the primary ­medium related) departments. Again, only a few such degree used in the early decades of the discipline, many more programs (e.g., Massachusetts Institute of Technology, sensing systems are now available, including radar, Ohio State University) currently exist in the United sonar, and lidar, which operate in different parts of the States. Notable examples of U.S. universities currently electro­magnetic radiation spectrum than the visual band offering an undergraduate degree in geomatics or a (Kraus, 2004). Moreover, while most early activities graduate degree in geodesy are listed in Table A.1 in involved photography from manned aircraft, platforms Appendix A. have since expanded to unmanned vehicles, satellites, Some 2-year colleges and associate degree pro- and handheld and industrial sensors. Construction of grams in universities offer programs in surveying or a mathematical model describing the relationship be- geomatics technology, which provide basic instruc- tween the image and the object or environment sensed, tion in the principles of geodesy, including coordinate called the sensor model, is fundamental to all activities systems and the use of GPS. There are many such of photogrammetry (McGlone et al., 2004). Given colleges across the United States, whose primary pur- these changes in the field, photogrammetry is now pose is to produce surveying and mapping technicians. defined as the art, science, and technology of extracting Examples include the Geomatics Technology Program reliable and accurate information about objects, phe- at Greenville Technical College (South Carolina) and nomena, and environments from acquired imagery and the Engineering Technology Program at Alfred State other sensed data, both passively and actively, within College (New York). a wide range of the electromagnetic energy spectrum. Course-only master’s degrees offered by some of ­Although its emphasis is on metric rather than thematic the institutions mentioned in Appendix A allow entry content, imagery interpretation, identification of tar- into some geodesy-related jobs. Some professional- gets, and image manipulation and analysis are required level education in geodesy is also available through con- to support most photogrammetric operations. tinuing education programs and short courses offered In photogrammetry, the Earth’s terrain is imaged by diverse organizations, such as the National Geodetic using overlapping images (photographs) taken from Survey, NavtechGPS, the Institute of Navigation, aircraft or hand-held cameras, linear scans of an area Pennsylvania State University, and the Michigan Tech- from a satellite (Figure 2.3), or data from active sen- nical University. sors, such as radar, sonar, and laser scanners. A single Undergraduate degrees or specialization in geo- image, which is a two-dimensional recording of the physics are available at a number of universities in three-dimensional (3D) world, is not sufficient to

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22 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE determine all three ground coordinates of any target point. Unless one of the three coordinates is known, such as the elevation from a digital elevation model, two or more images are required to accurately recover all three dimensions (Figure 2.4). Imagery, sensor and platform parameters, and metadata such as that from GPS and INS (inertial navigation system) are used in the photogrammetric exploitation. Most photogrammetric activities deal with cameras and sensors that are carefully built and calibrated to al- low direct micrometer-level measurements. However, an important branch of photogrammetry deals with less sophisticated instruments, such as those found on mobile phones, which require careful modeling and o ­ ften self-calibration. This branch is gaining impor- tance as the availability of imagery from nonmetric cameras grows. Many digital photogrammetric workstations en- able the overlap area of two images to be viewed stereo- scopically. Automated algorithms are commonly used to extract 3D features with high accuracy. Frequently, however, human judgment is required to edit, or some- times to override, the results from such algorithms. Evolution Photogrammetry began as a branch of surveying and was used for constructing topographic maps and for military mapping. It is still sometimes taught in survey- ing departments. Technological advances in surveying, the growth of photogrammetry, and the inclusion of related fields, such as geodesy, remote sensing (Box 2.2), cartography, and GIS, made the title “surveying” or “surveying engineering” inadequate for a department. The name geomatics or geomatics engineering was introduced to better capture this range of activities (see Box 2.1). At present, photogrammetry is taught in geomatics departments, as well as in other departments, such as geography and forestry. Photogrammetry has gone through three stages of FIGURE 2.3  Accurate photogrammetric reconstruction of the imaged terrain requires overlapping images and metadata. development: analog, analytical, and digital (Blachut (Top) Overlapping frame images produced by an aircraft; and Burkhardt, 1989). Analog instruments were built metadata include aircraft location determined from a constel- to optomechanically simulate the geometry of passive lation of GPS satellites, orientation determined from an inertial imaging and to allow the extraction, mostly graphically, navigation system, and/or GPS-determined ground control (red triangle). (Bottom) Overlapping images produced by linear ar- of information in the form of maps and other media. ray scans from a satellite. As computers became available, mathematical models of sensing were developed and algorithms were imple-

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 23 FIGURE 2.4  Recovery of three-dimensional target points requires at least two overlapping images, which is the basis for accurate stereo photogrammetry. BOX 2.2 Photogrammetry and Remote Sensing Both photogrammetry and remote sensing originated in aerial photography. Before it was called remote sensing, this field focused on identifying what is recorded in a photograph. By contrast, photogrammetry was concerned with where the recorded objects are in geographic space. Therefore, photogrammetry required more information about the photography, such as the camera characteristics (e.g., focal length, lens distortion) and aircraft trajectory (e.g., altitude, camera attitude). Airphoto interpretation requires less precise knowledge of the geometry of the photographs; it may suffice to know the approximate scale. The term remote sensing was introduced with the advent of systems that sense in several regions of the electromagnetic spectrum. For decades, remote sensing involved many of the same activities as photogrammetry at a coarser resolution, but contemporary remote sensing can image at resolu­ tions equivalent to those used in photogrammetry. What used to be almost entirely done by a human—the interpretation of photographs—has now been replaced by sophisticated algorithms based on mathematical pattern recognition and machine learning. Nevertheless, the fundamental tasks of the disciplines remain essentially the same. In photogrammetry, one deals with the rigorous mathematical modeling of the relationship between the sensed object and its representation by the sensor. Through such models, various types of information can be extracted from the imagery, such as precise positions, relative locations, dimensions, sizes, shapes, and all types of features. High accuracy is critical. For example, accurate modeling is used in multiband registration of multispectral imagery. In remote sensing, the goal is usually to transform an image so that it is suitable for mapping some property of the Earth surface synoptically, such as soil moisture or land cover. mented primarily in batch mode. The transition from Advances in optics, electronics, imaging, video, analog to analytical was epitomized by the introduction and computers during the past three decades have of the analytical plotter in 1961, which incorporated a led to significant changes in photogrammetry. Film is dedicated computer. The development of the digital being replaced by digital imagery, including ­magery i photogrammetric workstation ushered in the stage of from active sensors, such as radar and, more recently, digital photogrammetry.

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24 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE lidar.3 The operational environment and the variety of They understand the different platforms and have a activities and products have also changed dramatically. command of the techniques of least-squares adjust- The range of products has broadened beyond image ment and estimation from redundant measurements. products (e.g., single, rectified, and ortho­ectified r P ­ hotogrammetric scientists usually have a doctorate images; mosaics; radar products) to point and line and are capable of supervising or carrying out research products (e.g., targets, digital surface models, digital and modeling the various complex imaging systems. elevation models, point clouds, vectors) to relative They conceive of novel approaches and ways to deal information products (e.g., lengths, differences, with technological advances, whether in new sensors, areas, surfaces, volumes) to textured 3D models. new modes of image acquisition from orbital platforms Photogrammetry products now provide the base in- or aircraft, or in the integration and fusion of informa- formation for many geographic information systems tion from multiple sources. (GIS). Finally, many processes are being automated, allowing near-real-time applications. The next phase Education and Professional Preparation Programs may well be called on-demand photogrammetry, with many activities based online. It is likely that process- Education programs in photogrammetry (e.g., ing will be pushed upstream toward the acquisition Ohio State University, Cornell, Purdue University) platform, making it possible to obtain information flourished in the early and mid-1960s. At the time, products, rather than data, from an airborne or sat- photogrammetry was being used extensively by the De- ellite sensor. Direct 3D imaging may be imminent. fense Mapping Agency, the U.S. Geological Survey, the P ­ hotogrammetry will likely continue to play a sig- U.S. Coast and Geodetic Survey, the military services, nificant role in ascertaining precision and accuracy and the intelligence community. Demand for training of geospatial information, and to contribute to the was high, and these organizations sent significant num- complex problem of fusing imagery with other data. bers of employees to universities under programs such as the Long Term Full Time Training (LTFTT) pro- Knowledge and Skills gram. By the late 1980s and early 1990s, more than 25 photogrammetry programs were offering both ­master’s Photogrammetry classes are taught in under­ and doctorate degrees in the field. At the under­ graduate programs in surveying, surveying engineer- graduate level, photogrammetry was introduced as a ing, geomatics, or geomatics engineering, but none of small part of undergraduate courses in surveying and these programs in the United States offer a bachelor’s mapping. In the 1980s and 1990s, several institutions degree in photogrammetry. The graduates of such pro- (e.g., Ferris State, California State University, Fresno) grams may be employed in mapping firms, particularly offered lower-level photogrammetry courses as part of if they took an extra elective course in photogrammetry. their undergraduate bachelor’s programs in forestry, They would know how aerial photography and other geography, civil engineering, construction engineering, imagery is acquired and how to use it in stereoscopic surveying engineering, and, most recently, geomatics. processing systems to extract various types of map- About that time, the Defense Mapping Agency em- ping information. It is likely that they would receive barked on a modernization program (MARK 85 and significant on-the-job training by seniors in their firm. MARK 90) to convert to digital imagery and move The individuals who obtain a master’s degree toward automation. The agency’s focus on profes- in photogrammetry gain much more knowledge sional development shifted from learning fundamen- based on a strong mathematical foundation. Such tal principles to mastering skills to run software for p ­ hotogrammetrists or photogrammetric engineers photogrammetry applications. By the mid-1990s, the design algorithms to exploit various types of imagery. number of students taking classes through the LTFTT program and its successor Vector Study Program began 3 Although terms such as radargrammetry and lidargrammetry to decrease significantly, and the decline in enrollment are sometimes used to emphasize the type of sensor data being reduced support for educational programs offering a analyzed, the fundamentals of photogrammetry apply to all types substantial emphasis in photogrammetry. of sensor data.

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 25 At present, only a handful of programs in photo- part of the spectrum. Scientists at the Office of Naval grammetry exist in the United States (see Table A.2 in Research coined the term remote sensing to more accu- Appendix A). A few, such as those at Ohio State Uni- rately encompass the nature of the sensors that recorded versity and Purdue University, are top tier, yet are strug- energy beyond the optical region ( Jensen, 2007). gling to survive. Retiring faculty are not being replaced, Digital image processing originated in early spy and the number of faculty will soon decline below the satellite programs, such as Corona and the Satellite and critical mass needed to sustain these programs. Some Missile Observation System, and was further developed 2-year technology programs, such as in surveying or after the National Aeronautics and Space Administra- construction technology, offer hands-on training using tion’s (NASA’s) 1972 launch of the Earth Resource photogrammetric instruments to compile data. Most Technology Satellite (later renamed Landsat) with of these provide some photogrammetric skills but lack its Multi­pectral Scanner System (Estes and ­ensen, s J the rigorous mathematical basis of photogrammetry 1998). The first commercial satellite with point- programs in 4-year colleges. able multispectral linear array sensor technology was Outside of formal academic education, employers launched by SPOT Image, Inc., in 1986. Subsequent often provide in-house training, and some educational satellites launched by NASA and the private sector institutions and professional societies offer short have placed several sensor systems with high spatial courses ranging from a half day to a full week. The resolution in orbit, including IKONOS-2 (1 × 1 m American Society for Photogrammetry and Remote panchromatic and 4 × 4 m multispectral) in 1999, and Sensing regularly devotes a day or more to concurrent satellites launched by GeoEye, Inc. and DigitalGlobe, half-day or full-day short courses on specific topics in Inc. (e.g., 51 × 51 cm panchromatic) from 2000 to 2010. conjunction with its annual and semiannual meetings. Much of the imagery collected by these companies is Most of those who take these courses are employees used for national intelligence purposes in NGA pro- seeking professional development. grams such as ClearView and ExtendedView. Modern remote sensing science focuses on the REMOTE SENSING extraction of accurate information from remote sen- sor data. The remote sensing process used to extract Remote sensing is the science of measuring some information (Figure 2.5) generally involves (1) a clear property of an object or phenomenon by a sensor that is statement of the problem and the information required, not in physical contact with the object or phenomenon (2) collection of the in situ and remote sensing data to under study (Colwell, 1983). Remote sensing requires a address the problem, (3) transformation of the remote platform (e.g., aircraft, satellite), a sensor system (e.g., sensing data into information using analog and digital digital camera, multispectral scanner, radar), and the image processing techniques, and (4) accuracy assess- ability to interpret the data using analog and/or digital ment and presentation of the remote sensing-derived image processing. information to make informed decisions ( Jensen, 2005; Lillesand et al., 2008; Jensen and Jensen, 2012). Evolution State-of-the-art remote sensing instruments include analog and digital frame cameras, multi­ Remote sensing originated in aerial photography. spectral and hyperspectral sensors based on scanning The first aerial photograph was taken from a tethered or linear/area arrays, thermal infrared detectors, active balloon in 1858. The use of aerial photography dur- microwave radar (single frequency-single polarization, ing World War I and World War II helped drive the polarimetric, interferometric, and ground penetrating devel­ pment of improved cameras, films, filtration, o radar), passive microwave detectors, lidar, and sonar. and visual image interpretation techniques. During the Selected methods for collecting optical analog and late 1940s, 1950s, and early 1960s, new active sensor digital aerial photography, multispectral imagery, systems (e.g., radar) and passive sensor systems (e.g., hyper­pectral imagery, and lidar data are shown in s thermal infrared) were developed that recorded electro- Figure 2.6. Lidar imagery is increasingly being used magnetic energy beyond the visible and near-infrared to produce digital surface models, which include veg-

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26 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE FIGURE 2.5  Illustration of the process used to extract useful information from remotely sensed data. SOURCE: Jensen, J.R. and R.R. Jensen, Introductory Geographic Information Systems, ©2013. Printed and electronically reproduced by permission of Pearson Education, Inc., Upper Saddle River, New Jersey. etation structure and buildings information, and bare- mation beyond the local sensor web, which is useful earth digital terrain models (NRC, 2007; Renslow, for obtaining situational awareness (Delin and Small, 2012). 2009). Remote sensing systems are likely to find even Airborne and satellite remote sensing systems can greater application in the future when used in conjunc- now function as part of a sensor web to monitor and tion with other sensors in a sensor web environment. explore environments (Delin and Jackson, 2001). Un- like sensor networks, which merely collect data, each Knowledge and Skills sensor in a sensor web has its own microprocessor and can react and modify its behavior based on data col- Although curricula for educating remote sensing lected by other sensors in the web (Delin, 2005). The scientists and professionals have been developed,4 they individual sensors can be fixed or mobile and can be have not been widely adopted. Ideally, undergraduate deployed in the air, in space, and/or on the ground. A few of the sensors can be configured to transmit infor- 4 See .

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 27 FIGURE 2.6 Selected methods of collecting optical analog and digital aerial photography, multispectral imagery, hyperspectral imagery, and lidar data. SOURCE: Jensen, J.R., Remote Sensing of the Environment: An Earth Resource Perspective, 2nd, ©2007. Printed and electronically reproduced by permission of Pearson Education, Inc., Upper Saddle River, New Jersey. and graduate students specializing in remote sensing at use a GIS (Foresman et al., 1997). Remote sensing universities are well versed in a discipline (e.g., forestry, scientists and professionals must be able to analyze civil engineering, geography, geology); understand how digital remote sensor data using a diverse array of digital electromagnetic energy interacts with the atmosphere image processing techniques, such as radiometric and and various kinds of targets; are trained in statistics, geometric preprocessing, enhancement (e.g., image mathematics, and programming; and know how to fusion, filtering), classification (e.g., machine learning,

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28 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE object-oriented image segmentation, support vector CARTOGRAPHIC SCIENCE machines), change detection and animation, and the integration of digital remote sensor data with other Cartography focuses on the application of math- geospatial data (e.g., soil, elevation, slope) using a GIS ematical, statistical, and graphical techniques to the ( Jensen et al., 2009). Skills are also needed to interpret science of mapping. The discipline deals with theory real-time video imagery collected from satellite, sub­ and techniques for understanding the creation of maps orbital, and unmanned aerial vehicles. and their use for positioning, navigation, and spatial reasoning. Components of the discipline include the principles of information design for spatial data, Education and Professional Preparation Programs the impact of scale and resolution, and map projec- There are no departments of remote sensing in tions (Slocum et al., 2009). Themes often analyzed U.S. universities (Mondello et al., 2006, 2008). Instead, include evaluation of design parameters—especially a variety of departments offer degree tracks in remote those involved with symbol appearance, hierarchy, and sensing as part of a degree in other fields, including placement—and assessment of visual effectiveness. Other topics emphasized include transformations and • geography (all types of remote sensing), algorithms, data precision, and data quality and uncer- • natural resources/environmental science (all tainty. Cartography also focuses on automation in the types of remote sensing), production, interpretation, and analysis of map displays • engineering (sensor system design and all types in paper, digital, mobile device, and online form. of remote sensing), Among the key tasks that fall within cartography • geomatics (all types of remote sensing), at NGA are maintaining geographic names data, pro- • geology/geoscience (all types of remote sensing ducing standard map coverage for areas outside the and ground penetrating radar), United States, and nautical and aeronautical charting • forestry (all types of remote sensing, but espe- (e.g., Figure 2.7). The operational demands of the cially lidar), armed services for digital versions of standard maps and • anthropology (especially the use of aerial pho- charts have expanded with the increased availability of tography and ground penetrating radar), and automated navigation systems. • marine science (especially the use of aerial pho- tography and sonar). Evolution Few of these programs offer lidar courses; most lidar The roots of cartography are positioned in geodesy instruction takes place within other remote sensing and surveying, in exploration for minerals and natural courses. resources, in maritime trade, and in sketching and Dozens of departments at 4-year universities ­ ffer o lithographic renderings of landscapes by geologists degree tracks in remote sensing. A selected list of and geographers. The formal discipline of cartography departments with a remote sensing-related concentra- dates back to the late 1700s, when William Playfair tion, track, or degree appears in Table A.3 in Appen- began mapping thematic information on demographic, dix A. Geography programs offer more remote sensing health, and socioeconomic characteristics. Military courses and grant more degrees specializing in all types and strategic applications, particularly navigation and of remote sensing than any other discipline. ballistics, have driven many of the major advances in As far as can be determined, few remote sensing cartography. Improvements in printing, flight, plastics, courses are offered at 2-year colleges, and no degrees and electronics supported cartographic production, are granted with a specialization in remote sensing. distribution, preservation, spatial registration, and Remote sensing education is also available through automation. workshops and webinars organized by professional The end of World War II created a surplus of societies and online instruction and degrees offered by trained geographers who moved from military intel- universities. ligence to academic positions. During the 1970s and

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 29 FIGURE 2.7  NGA digital operational navigational chart covering the Korean peninsula at 1:1M scale, displayed in the Falconview software. SOURCE: Clarke (2013b). 1980s, graduate programs specializing in cartography for personnel trained in processing spatial information began to emerge at about a dozen universities. Begin- increased. In response, the emphasis of university cur- ning in the early 1980s, GIS began to flourish, largely ricula shifted from cartography to geographic informa- due to the decision to automate the U.S. Decennial tion science (Box 2.3). Census and map production at the U.S. Geological Cartographic skills in information design, data Survey (McMaster and McMaster, 2002). Demands modeling, map projections, coordinate systems, and

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30 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE planning, resource exploration in hostile or inacces- BOX 2.3 sible environments, modeling complex environmental Geographic Information Science scenarios, and tracking the spread of disease. A super- set of this area, called visual analytics, is described in Geographic information science is a term coined in a seminal article by Michael F. Goodchild (1992) to encompass the scientific Chapter 3. questions that arise from geographic information, including both The transition from traditional cartography to geo- research about GIS that would lead eventually to improvements in graphic information science in universities has changed the technology and research with GIS that would exploit the tech­ the mix of knowledge and skills being taught. Basic nology in the advancement of science (Goodchild, 2006). As such, cartographic skills remain a prerequisite to geographic geographic information science includes aspects of cartography, information science training, which requires under- computer science, spatial statistics, cognitive science, and other fields that pertain to the analysis of spatial information, as well as standing of projections, scale, and resolution. Virtually societal and ethical questions raised by the use of GIS (e.g., issues all GIS textbooks include basic information on carto- of privacy). graphic scale, map projections, coordinate systems, and the size and shape of the Earth. Knowledge about the principles of graphic display has been deemphasized in most curricula, even though map displays in GIS environments are often created by analysts and are sub- statistical analysis for mapping remain an important ject to misinterpretation. The traditional cartographic foundation for many tasks in geospatial intelligence. training in map production has been replaced by train- For example, an ability to create and interpret inter- ing in cartography, in detection and identification of active and real-time graphical displays of geographic spatial relationships, in spatial data modeling, and in spaces (e.g., streaming video footage of enemy ter- the application of mapping to spatial pattern analysis. rain) or of statistical information spaces (e.g., statisti- Many curricula have also incorporated coursework to cal clusters of demographic, economic, political, and train students in the use of GIS. In the past decade, religious characteristics) could help identify latent or most curricula have introduced coursework in software developing terrorist cells. Skills required for nautical programming, database management, and web-based charting include a working knowledge of calculus, mapping and data delivery. solid programming skills, and expertise in converting The minimum cartographic skills needed for among international geodetic datums and spheroids. A professional cartographers include a demonstrated nautical charting specialist must also be able to compile ability to work with basic descriptive and inferential information from various sources and establish a sta- statistics; an ability to program in C++, Java, or a script- tistical confidence interval for each information source ing language such as Python; understanding of the and to quantify data reliability. principles of information design (Bertin, 1967); and An emerging area of cartography, which addresses a working knowledge of current online and archived the design and analysis of statistical information dis- data sources and software for their display. Professional plays, has been called geovisualization (Dykes et al., cartographers are capable of handling large data sets, of 2005) or geographic statistical visualization (Wang et undertaking basic and advanced statistical analysis (dif- al., 2002). Whereas scientific visualization is focused ference of means, correlation, regression, interpolation) on realistic renderings of surfaces, solids, and land- in a commercial software environment, of interpreting scapes using computer graphics (McCormick et al., spatial patterns in data, and of representing these pat- 1987; Card et al., 1999), geovisualization emphasizes terns effectively on charts and map displays. information design that links geographic and statisti- Cartographic skills used in the subdiscipline of cal patterns (e.g., Figure 2.8). The primary purpose of geo­ isualization include map animation, geographic v geovisualization is to illustrate spatial information in data exploration, interactive mapping, uncertainty ways that enable understanding for decision making visualization, mapping virtual environments, and col- and knowledge construction (MacEachren et al., 2004). laborative geovisualization (Slocum et al., 2009). Its practical applications include urban and strategic

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 31 FIGURE 2.8  Example of a geovisualization technique that allows the display of events unfolding over time (vertical axis) and space (map). SOURCE: GeoTime is a registered trademark of Oculus Info Inc. Image used by permission of Oculus Info Inc. Education and Professional Preparation Programs There are four major career paths in ­ artography: c (1) information design, which focuses on design and A few dozen academic geography departments in graphic representation for topographic, reference (­atlas), the United States offer a degree track or concentration or thematic mapping; (2) GIS analysis (see below); or a certificate with cartography or mapping in the title (3) visual analytics (see Chapter 3); or (4) production of the degree or certificate (see examples in Table A.4 cartography, which focuses on printing and reproduc- in Appendix A). Students enrolled in these degree tion. As the demand for production ­ artographers c tracks or certificate programs are commonly required d ­ eclines, fewer programs offer a primary or even a to take two or more courses related to cartography secondary focus on printing and reproduction. The and mapping, as well as a course in basic statistics. At demand for web, mobile, and online map produc- present, the most diverse undergraduate curriculum in tion continues to grow, however. It is possible to take c ­ artography is offered by the University of Wisconsin. web or mobile coursework at some U.S. colleges and Strong graduate programs in cartography are harder universities, but presently there are no certificate or to identify since so many graduate curricula have been degree programs in these topics. There is a demand for folded into geographic information science work.

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32 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE professionally trained cartographic designers to produce resentation, visualization, and analysis of information atlas and topographic map designs, and undergraduate that pertains to a particular location on the Earth’s training in this area can be found at several universities, surface. Geospatial analysis emphasizes the extraction such as Oregon State University, Pennsylvania State of information, insight, and knowledge from the GIS University, and Salem State University. through the application of a wide range of analytical A number of 2-year colleges offer coursework in techniques, including visualization, data exploration, cartography and geographic information science. The statistical and econometric modeling, process model- shorter time required to complete a degree coupled with ing, and optimization (e.g., Figure 2.9). smaller class sizes (relative to larger universities) pro- vides an environment conducive to hands-on training, Evolution which is essential preparation for good cartographic practice. Laboratory assignments, courses including GIS evolved to a reasonably well-defined discipline practical work, and semester projects which are ­ fferedo from a variety or origins, including cartography, land in 2-year colleges may not be offered until junior or management, computer science, urban planning, and senior year at universities, simply due to the size of the landscape architecture. Geospatial analysis has its roots student population. The disadvantage of the 2-year col- in analytical cartography, the quantitative approach to lege curricula, however, is that less attention is paid to geography pioneered at the University of Washington, computational and statistical skills, mostly due to the and the development of quantitative spatial methods shortened time span. in regional science and operations research dating back Many universities offer professional preparation in to the early 1960s. Its early scope is represented by geographic information science, and, in the best pro- the classic book Spatial Analysis: A Reader in Statisti- grams, cartography courses are a prerequisite to GIS cal Geography (Berry and Marble, 1968). While often courses. Most professional preparation in cartography identified with spatial statistics, geospatial analysis that is relevant to geospatial intelligence focuses on encompasses a range of techniques from visualization GIS analysis or visual analytics. GIS analysts with to optimization. The need to develop analytical tech- ­cartographic training have a better understanding of pro- niques to accompany the technology of GIS was raised jections and scale dependence. Important spatial patterns by a number of scholars in the late 1980s and early may be evident only in data within specific scale ranges, 1990s (e.g., Goodchild, 1987; Anselin and Getis, 1992; and cartographers are trained to be sensitive to relation- Goodchild et al., 1992). Compilations of early progress ships between spatial process and spatial or temporal in GIS and geospatial analysis appear in Fotheringham resolution. Visual analytics experts with cartographic and Rogerson (1994) and Fischer and Getis (1997), training bring an understanding of spatial relation- and comprehensive overviews of the state of the art ships (also known as spatial thinking or reasoning; see are provided in Fotheringham and Rogerson (2009), NRC, 2006), which is endemic to geographic training. Fischer and Getis (2010), and de Smith et al. (2010). Career preparation in cartography also includes training Both GIS and geospatial analysis are changing in basic statistics, which is necessary for exploring and rapidly as a result of the creation of Google Earth and interpreting spatial patterns. Geovisualization shows similar services, the ready availability of technology to great promise for integrating geographic, cognitive, and support location-based services and analysis, and the statistical skill sets for creation, analysis, and interpreta- use of the Internet as cyberinfrastructure. These tech- tion of geographical and statistical information displays, nological changes challenge the traditional model of an all of which are valuable for military intelligence. industry dominated by the products of a small number of vendors. Increasingly, GIS is offered as a web service GEOGRAPHIC INFORMATION SYSTEMS and credible open-source competitors to the com- AND GEOSPATIAL ANALYSIS mercial platforms are appearing, supported by open standards developed by organizations such as the Open Geographic information systems are computer- Geospatial Consortium. This development has signifi- based systems that deal with the capture, storage, rep- cantly democratized access to geographic information,

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CORE AREAS OF GEOSPATIAL INTELLIGENCE 33 FIGURE 2.9  Screen shot of an application of the GeoDa software for spatial data analysis (Anselin et al., 2006) illustrating an exploration of spatial patterns of house prices in Seattle, Washington. The different graphs and maps are dynamically linked in the sense that selected observations (highlighted in yellow) are simultaneously selected in all windows. SOURCE: Anselin (2005). which relies increasingly on a web browser to query, landscape architecture, ecology, anthropology, and analyze, and visualize spatial data. Crowd­ourcing is s civil engineering. The core curriculum for GIS educa- becoming more important, changing the role of tradi­ tion is laid out in the “Body of Knowledge” (DiBiase tional data providers, and the notion of c yberGIS ­ et al., 2006), which is used by many higher education (extensions of cyberinfrastructure frameworks that ac- institutions to help structure GIS offerings.5 The core count for the special characteristics of geospatial data curriculum outlines a range of necessary knowledge and geospatial analytical operations, e.g., Wang, 2010) and skills, including a solid foundation in cartography, is around the corner. Research in geospatial analysis is information systems, computer science, geocomputa- embracing the study of space-time dynamics associated tion, statistics, and operations research. Most university with both human and physical phenomena, increas- programs include coursework in a subset of these skills, ingly supported by massive quantities of data. This but few deliver the full range of skills. new direction requires new conceptual frameworks, methods, and computational techniques and is driving Education and Professional Preparation Programs a rapidly evolving state of the art. GIS educational programs and their degree of Knowledge and Skills technical sophistication vary widely and range from community college training to undergraduate and GIS and geospatial analysis are taught in under- graduate and graduate curricula in a wide range of uni- 5 Community input is currently being gathered for the second versity programs, such as geography, urban planning, edition of the Body of Knowledge.

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34 FUTURE U.S. WORKFORCE FOR GEOSPATIAL INTELLIGENCE graduate certificates to master’s and professional master’s cates or degrees are available from traditional or online programs. There are some 189 GIS degree programs in university programs, both nonprofit and for-profit. the United States, and more than 400 community col- Commercial vendors offer professional training or edu- leges and technical schools offer some form of training cation, typically in the form of online training modules in geospatial technologies (e.g., see Table A.5 in Ap- and in-person training sessions. Perhaps the largest pendix A). In contrast, only a handful of U.S. degree or and best known industry training is provided by Envi- certificate programs have an explicit focus on geospatial ronmental Systems Research Institute (ESRI), which analysis. For example, the University of ­ ennsylvania P offers formal technical certification programs that deal offers a master’s in urban spatial ­nalytics and Duke a with various aspects of GIS and spatial analysis (e.g., University offers a geospatial analysis certificate. Various desktop, developer, enterprise). Coursework is offered aspects of geospatial analysis are also covered in graduate online and in 1- to 4-day instructor-led workshops. degree programs in statistics, public health, criminology, After participants pass a test, they are provided with ­archeology, urban planning, ecology, industrial engineer- a certificate. ing, and other areas. For example, statistics programs Professional societies (e.g., Association of Ameri- with a heavy emphasis on spatial statistics include the can Geographers, American Planning Association) University of ­ innesota (bio­tatistics), the University M s sponsor ad hoc training sessions in basic to advanced of Washington (environmental and bio­tatistics), and s techniques. These sessions are commonly funded by Duke University (environmental and biostatistics). federal agencies such as the National Science Founda- Advanced courses in spatial optimization are offered in tion’s Center for Spatially Integrated Social Science, the geography program at the University of California, or carried out as part of advanced professional training Santa Barbara, in geography and industrial engineering programs. A number of scholarly conferences include programs at ­ rizona State University, and in various A 1- or 2-day short courses or workshops focusing on programs at Johns Hopkins University and the Univer- particular software programs or advanced methods. sity of Connecticut. For example, the GeoStat 2011 conference had a Training in GIS and geospatial analysis is also 1-week course on spatial statistics with open-source delivered through other channels. Professional certifi- software.