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82-521: The award was established by the AGU in 2013 to recognize the groundbreaking contributions of individuals whose achievements extend beyond the scope of traditional scientific honors. The award is annually given to between one and five individuals with notable achievements in societal impact, service to the Earth and space communities, scientific leadership, and promotion of the talent and career pool. The Ambassador Award

164-596: A geocentric coordinate frame. One such frame is WGS84 , as well as frames by the International Earth Rotation and Reference Systems Service ( IERS ). GNSS receivers have almost completely replaced terrestrial instruments for large-scale base network surveys. To monitor the Earth's rotation irregularities and plate tectonic motions and for planet-wide geodetic surveys, methods of very-long-baseline interferometry (VLBI) measuring distances to quasars , lunar laser ranging (LLR) measuring distances to prisms on

246-406: A "reference frame" for the same. The ISO term for a datum transformation again is a "coordinate transformation". General geopositioning , or simply positioning, is the determination of the location of points on Earth, by myriad techniques. Geodetic positioning employs geodetic methods to determine a set of precise geodetic coordinates of a point on land, at sea, or in space. It may be done within

328-407: A chief digital officer. The AGU offers several awards, medals and fellowships. AGU nominates members for fellowship in the society. According to the AGU website "To be elected a Fellow of AGU is a special tribute for those who have made exceptional scientific contributions to Earth and space sciences as valued by their peers and vetted by section and focus group committees." A maximum of 0.1% of

410-461: A consequence of fossil fuel combustion and other human activities. These elevated concentrations of greenhouse gases are predicted to persist in the atmosphere for times ranging to thousands of years. Increasing concentrations of carbon dioxide and other greenhouse gases affect the Earth-atmosphere energy balance, enhancing the natural greenhouse effect and thereby exerting a warming influence at

492-566: A coordinate system ( point positioning or absolute positioning ) or relative to another point ( relative positioning ). One computes the position of a point in space from measurements linking terrestrial or extraterrestrial points of known location ("known points") with terrestrial ones of unknown location ("unknown points"). The computation may involve transformations between or among astronomical and terrestrial coordinate systems. Known points used in point positioning can be GNSS continuously operating reference stations or triangulation points of

574-420: A country, usually documented by national mapping agencies. Surveyors involved in real estate and insurance will use these to tie their local measurements. In geometrical geodesy, there are two main problems: The solutions to both problems in plane geometry reduce to simple trigonometry and are valid for small areas on Earth's surface; on a sphere, solutions become significantly more complex as, for example, in

656-421: A discipline of applied mathematics . Geodynamical phenomena, including crustal motion, tides , and polar motion , can be studied by designing global and national control networks , applying space geodesy and terrestrial geodetic techniques, and relying on datums and coordinate systems . Geodetic job titles include geodesist and geodetic surveyor . Geodesy began in pre-scientific antiquity , so

738-774: A four-digit article number. In 2012 the journals and books, including over one and a half million pages of legacy content, were transferred to the Wiley Online Library . John Wiley & Sons were recognized for this work with the IT Project Team of the Year Award at the UK IT Industry Awards for 2013. Five AGU journals are open access only: AGU Advances , Earth’s Future , Earth and Space Science , GeoHealth , JAMES , and Space Weather . The remainder are delayed open access journals , having free access after

820-412: A full transition to electronic publishing in 2001. For all its journals, the electronic version became the publication of record. This was accompanied by a new identification scheme for articles that entirely did away with sequential page numbers. Instead, each article had a digital object identifier (DOI). As an example, 10.1029/2001GL014304 consists of the publisher identifier (10.1029), the year (2001),

902-428: A full-time professional administrator. The post was renamed Executive Secretary and Waldo E. Smith was hired. He served until 1970 and then Athelstan Spilhaus, Jr. was hired as executive director. Christine McEntee replaced him in 2010. Medals have been named after Fleming and Smith. The AGU leadership in 2021 included, in addition to the president, a CEO, 4 executive vice presidents, 6 vice presidents, 7 directors, and

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984-418: A higher-order network. Traditionally, geodesists built a hierarchy of networks to allow point positioning within a country. The highest in this hierarchy were triangulation networks, densified into the networks of traverses ( polygons ) into which local mapping and surveying measurements, usually collected using a measuring tape, a corner prism , and the red-and-white poles, are tied. Commonly used nowadays

1066-416: A large extent, Earth's shape is the result of rotation , which causes its equatorial bulge , and the competition of geological processes such as the collision of plates , as well as of volcanism , resisted by Earth's gravitational field. This applies to the solid surface, the liquid surface ( dynamic sea surface topography ), and Earth's atmosphere . For this reason, the study of Earth's gravitational field

1148-414: A letter signed by 100 scientists was delivered to the AGU, requesting that they cut all ties with ExxonMobil and other companies that foster climate misinformation. The AGU Board of Directors met on April 22, 2016, and voted to continue accepting sponsorship from ExxonMobil, arguing that there was not unequivocal evidence that ExxonMobil continues to participate in climate misinformation. Instead of making

1230-509: A physical (real-world) realization of a coordinate system used for describing point locations. This realization follows from choosing (therefore conventional) coordinate values for one or more datum points. In the case of height data, it suffices to choose one datum point — the reference benchmark, typically a tide gauge at the shore. Thus we have vertical datums, such as the NAVD 88 (North American Vertical Datum 1988), NAP ( Normaal Amsterdams Peil ),

1312-408: A plenary session of the annual Fall Meeting with a call for scientists to engage in protest against climate change. AGU removed their research presentations from the meeting, banned them from participation, launched a misconduct inquiry, and complained to Abramoff's employer, Oak Ridge National Laboratory . Kalmus and Abramoff further claimed that AGU threatened to have them arrested if they returned to

1394-482: A projection is UTM ( Universal Transverse Mercator ). Within the map plane, we have rectangular coordinates x and y . In this case, the north direction used for reference is the map north, not the local north. The difference between the two is called meridian convergence . It is easy enough to "translate" between polar and rectangular coordinates in the plane: let, as above, direction and distance be α and s respectively, then we have The reverse transformation

1476-965: A result of a 2016 workshop AGU convened to address the challenge of sexual and gender-based harassment, with co-sponsorship by the American Association for the Advancement of Science , the American Chemical Society (ACS), the American Geosciences Institute (AGI), the Association for Women Geoscientists (AWG), and the Earth Science Women's Network (ESWN). Additionally, AGU staff are trained in how to address incidents of harassment at their annual meeting and wear "Safe AGU" buttons to signify themselves as resources. On February 27, 2018, AGU CEO Chris McEntee testified before

1558-593: A second meeting was held every Spring (April through May) in locations around the world. The latter grew out of AGU's annual Spring meeting, which had been held for many years in Baltimore , until declining interest caused AGU to move the meeting to different locations, starting with Boston in 1998. With the 2003 meeting in Nice , France, it became known as the Joint Assembly because AGU co-sponsors it with other societies such as

1640-481: A series expansion — see, for example, Vincenty's formulae . As defined in geodesy (and also astronomy ), some basic observational concepts like angles and coordinates include (most commonly from the viewpoint of a local observer): The reference surface (level) used to determine height differences and height reference systems is known as mean sea level . The traditional spirit level directly produces such (for practical purposes most useful) heights above sea level ;

1722-502: A set of four criteria are met. However, when Texaco 's corporate library made systematic copies of journal articles for its collection, AGU and five other publishers took Texaco to court. The judges found for AGU. Texaco was fined and agreed to retroactively purchase a license from the Copyright Clearance Center . The presidents of the AGU have been: While more than 40 presidents have provided scientific leadership for

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1804-587: A setback when its chairman, Peter Gleick , announced that he had lied to obtain internal documents from the Heartland Institute and then leaked them to the public. Gleick, a climate scientist and recipient of the MacArthur Fellowship , said he was motivated by frustration with the efforts of groups such as the Heartland Institute to attack climate science and scientists, but admitted that it

1886-464: A short-term political statement, the Board wished to engage with the energy industry over the long term. In response, Senator Sheldon Whitehouse and Representative Ted Lieu sent a critical letter saying that ExxonMobil continues to fund climate denial and is misleading the AGU. The Union of Concerned Scientists also sent a letter urging them to reconsider. However, in a meeting on September 23, 2016,

1968-543: A single global, geocentric reference frame that serves as the "zero-order" (global) reference to which national measurements are attached. Real-time kinematic positioning (RTK GPS) is employed frequently in survey mapping. In that measurement technique, unknown points can get quickly tied into nearby terrestrial known points. One purpose of point positioning is the provision of known points for mapping measurements, also known as (horizontal and vertical) control. There can be thousands of those geodetically determined points in

2050-635: A two-year rolling period. The AGU hosts a number of blogs, collectively known as the AGU Blogosphere , informally publishing frequent updates on the Earth and space sciences. AGU publications are copyrighted, but in the United States many exceptions to the exclusive rights of copyright are allowed under the fair use provision, part of the Copyright Act of 1976 . Making copies of publications are allowed for such uses as teaching and research as long as

2132-454: Is approximately the same as the direction of the plumbline, i.e., local gravity, which is also the normal to the geoid surface. For this reason, astronomical position determination – measuring the direction of the plumbline by astronomical means – works reasonably well when one also uses an ellipsoidal model of the figure of the Earth. One geographical mile, defined as one minute of arc on the equator, equals 1,855.32571922 m. One nautical mile

2214-466: Is GPS, except for specialized measurements (e.g., in underground or high-precision engineering). The higher-order networks are measured with static GPS , using differential measurement to determine vectors between terrestrial points. These vectors then get adjusted in a traditional network fashion. A global polyhedron of permanently operating GPS stations under the auspices of the IERS is the basis for defining

2296-485: Is based on the information provided by the AGU . American Geophysical Union The American Geophysical Union ( AGU ) is a 501(c)(3) nonprofit organization of Earth, atmospheric , ocean , hydrologic , space , and planetary scientists and enthusiasts that according to their website includes 130,000 people (not members). AGU's activities are focused on the organization and dissemination of scientific information in

2378-518: Is called physical geodesy . The geoid essentially is the figure of Earth abstracted from its topographical features. It is an idealized equilibrium surface of seawater , the mean sea level surface in the absence of currents and air pressure variations, and continued under the continental masses. Unlike a reference ellipsoid , the geoid is irregular and too complicated to serve as the computational surface for solving geometrical problems like point positioning. The geometrical separation between

2460-608: Is co-sponsored by the International Union of Radio Science . The journal Earth Interactions is published in partnership with the American Meteorological Society (AMS) and the Association of American Geographers (AAG). In addition, International Journal of Geomagnetism and Aeronomy is no longer published and AGU distributes Chinese Journal of Geophysics and Nonlinear Processes in Geophysics . Many of

2542-416: Is described by (apparent) sidereal time , which accounts for variations in Earth's axial rotation ( length-of-day variations). A more accurate description also accounts for polar motion as a phenomenon closely monitored by geodesists. In geodetic applications like surveying and mapping , two general types of coordinate systems in the plane are in use: One can intuitively use rectangular coordinates in

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2624-399: Is given by: In geodesy, point or terrain heights are " above sea level " as an irregular, physically defined surface. Height systems in use are: Each system has its advantages and disadvantages. Both orthometric and normal heights are expressed in metres above sea level, whereas geopotential numbers are measures of potential energy (unit: m s ) and not metric. The reference surface is

2706-591: Is no persuasive evidence that human activity is warming the planet. The court rejected Cuccinelli's demand. However, such legal challenges continue, so in 2012 AGU entered in a partnership with the Climate Science Legal Defense Fund to offer legal counseling at the Fall Meeting. In 2011, AGU created a Task Force on Scientific Ethics, "to review and update existing policies and procedures for dealing with scientific misconduct." This effort received

2788-578: Is off by 200 ppm in the current definitions). This situation means that one kilometre roughly equals (1/40,000) * 360 * 60 meridional minutes of arc, or 0.54 nautical miles. (This is not exactly so as the two units had been defined on different bases, so the international nautical mile is 1,852 m exactly, which corresponds to rounding the quotient from 1,000/0.54 m to four digits). Various techniques are used in geodesy to study temporally changing surfaces, bodies of mass, physical fields, and dynamical systems. Points on Earth's surface change their location due to

2870-457: Is one minute of astronomical latitude. The radius of curvature of the ellipsoid varies with latitude, being the longest at the pole and the shortest at the equator same as with the nautical mile. A metre was originally defined as the 10-millionth part of the length from the equator to the North Pole along the meridian through Paris (the target was not quite reached in actual implementation, as it

2952-421: Is purely geometrical. The mechanical ellipticity of Earth (dynamical flattening, symbol J 2 ) can be determined to high precision by observation of satellite orbit perturbations . Its relationship with geometrical flattening is indirect and depends on the internal density distribution or, in simplest terms, the degree of central concentration of mass. The 1980 Geodetic Reference System ( GRS 80 ), adopted at

3034-447: Is the science of measuring and representing the geometry , gravity , and spatial orientation of the Earth in temporally varying 3D . It is called planetary geodesy when studying other astronomical bodies , such as planets or circumplanetary systems . Geodesy is an earth science and many consider the study of Earth's shape and gravity to be central to that science. It is also

3116-480: Is the only Union level award of the AGU whose recipients are automatically made AGU Fellows. The Ambassador Award was approved by the AGU Board of Directors On 20 September 2013 as a step forward by the AGU in building the community of scientists whose dedication to reaching across boundaries has made science visible and compelling, empowered new voices, and inspired future generations of researchers. The following list

3198-420: Is the only union-level award of the AGU whose recipients are automatically made AGU Fellows. The Ambassador Award was approved by the AGU Board of Directors on September 20, 2013 as a step forward by the AGU in building the community of scientists whose dedication to reaching across boundaries has made science visible and compelling, empowered new voices, and inspired future generations of researchers. The award

3280-752: The Geochemical Society , the Mineralogical Society of America (MSA), the Canadian Geophysical Union (CGU), and the European Geosciences Union (EGU). The Fall Meeting had more than 25,000 attendees in 2018. In addition to the Fall meeting that covers all areas of the geophysical sciences, AGU sponsors many specialized meetings that are intended to serve the needs of particular scientific disciplines or geographical areas, including

3362-664: The House Committee on Science, Space, & Technology Subcommittee on Research and Technology Hearing – A Review of Sexual Harassment and Misconduct in Science. His testimony was alongside those of Rhonda Davis, head of the National Science Foundation 's (NSF) Office of Diversity and Inclusion, Kathryn Clancy , an anthropologist at the University of Illinois at Urbana-Champaign , and attorney Kristina Larsen. In July 2019,

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3444-446: The geoid , an equigeopotential surface approximating the mean sea level as described above. For normal heights, the reference surface is the so-called quasi-geoid , which has a few-metre separation from the geoid due to the density assumption in its continuation under the continental masses. One can relate these heights through the geoid undulation concept to ellipsoidal heights (also known as geodetic heights ), representing

3526-527: The geoids within their areas of validity, minimizing the deflections of the vertical over these areas. It is only because GPS satellites orbit about the geocenter that this point becomes naturally the origin of a coordinate system defined by satellite geodetic means, as the satellite positions in space themselves get computed within such a system. Geocentric coordinate systems used in geodesy can be divided naturally into two classes: The coordinate transformation between these two systems to good approximation

3608-702: The tachymeter determines, electronically or electro-optically , the distance to a target and is highly automated or even robotic in operations. Widely used for the same purpose is the method of free station position. Commonly for local detail surveys, tachymeters are employed, although the old-fashioned rectangular technique using an angle prism and steel tape is still an inexpensive alternative. As mentioned, also there are quick and relatively accurate real-time kinematic (RTK) GPS techniques. Data collected are tagged and recorded digitally for entry into Geographic Information System (GIS) databases. Geodetic GNSS (most commonly GPS ) receivers directly produce 3D coordinates in

3690-461: The topographic surface of Earth — is also realizable. The locations of points in 3D space most conveniently are described by three cartesian or rectangular coordinates, X , Y , and Z . Since the advent of satellite positioning, such coordinate systems are typically geocentric , with the Z-axis aligned to Earth's (conventional or instantaneous) rotation axis. Before the era of satellite geodesy ,

3772-568: The AGU Board approved a new Organizational Support Policy. The policy covers subjects such as advertorials and member surveys. It requires that partnerships contribute to AGU's mission, vision and goals and that the AGU "apply vetting to ascertain that partners are not engaged in false misinterpretations of science." The sponsorship of AGU by ExxonMobil became a source of concern for many members after evidence surfaced that ExxonMobil had known about climate change for decades but had actively worked to undermine climate science. On February 22, 2016,

3854-524: The AGU since 1919, operational leadership has been provided by a larger team. The first senior team member was John Adam Fleming , who was elected Secretary in 1925 and changed the name of his position to General Secretary. He served as a volunteer while working at the Department of Terrestrial Magnetism at the Carnegie Institution. By 1943, with the membership nearing 2,000, AGU recognized the need for

3936-463: The AGU took place on April 23, 1920. In attendance were 25 members. Up to 1930, the number of members was restricted and members were elected. In 1932 the first annual dues of US$ 2 were imposed. The membership grew to 4,600 in 1950; 13,000 in 1980; and 26,000 in 1990. As of 2018, it had 62,000 members from 137 countries. AGU publishes the online magazine Eos and more than twenty peer-reviewed scientific journals : The journal Radio Science

4018-716: The AGU was awarded a three-year grant from the Alfred P. Sloan Foundation to launch the AGU Ethics and Equity Initiative, a collaboration among the AGU and the National Center for Professional and Research Ethics at the University of Illinois at Urbana–Champaign . The initiative will tackle issues around sexual harassment and gender-based discrimination by developing new educational resources and tracking tools to measure impact. In December 2022, AGU punished climate scientists Rose Abramoff and Peter Kalmus for misconduct, who interrupted

4100-405: The Board upheld its previous decision. In November 2021, AGU announced in a video presentation that, as a consequence of its Environmental, social, and corporate governance policies, it no longer had any direct investments in fossil-fuel companies and it was beginning to divest its investment portfolio from mutual fund holdings in fossil-fuel companies. Geodesy Geodesy or geodetics

4182-724: The Earth's deep interior; tectonophysics ; volcanology , geochemistry , and petrology . AGU holds an annual meeting every December (known as the Fall Meeting). Until 2017, the meeting was held yearly in San Francisco. Because of renovations at the San Francisco venue, the 2017 meeting took place in New Orleans and the 2018 meeting in Washington, DC. It returned to San Francisco in 2019 and its location will rotate among San Francisco, New Orleans, Chicago, and Washington, DC . Previously,

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4264-430: The Earth's surface. The statement continued, Present understanding of the Earth climate system provides a compelling basis for legitimate public concern over future global and regional-scale changes resulting from increased concentrations of greenhouse gases. After a discussion of scientific uncertainties the statement concluded AGU believes that the present level of scientific uncertainty does not justify inaction in

4346-485: The GRS 80 reference ellipsoid. The geoid is a "realizable" surface, meaning it can be consistently located on Earth by suitable simple measurements from physical objects like a tide gauge . The geoid can, therefore, be considered a physical ("real") surface. The reference ellipsoid, however, has many possible instantiations and is not readily realizable, so it is an abstract surface. The third primary surface of geodetic interest —

4428-611: The Kronstadt datum, the Trieste datum, and numerous others. In both mathematics and geodesy, a coordinate system is a "coordinate system" per ISO terminology, whereas the International Earth Rotation and Reference Systems Service (IERS) uses the term "reference system" for the same. When coordinates are realized by choosing datum points and fixing a geodetic datum, ISO speaks of a "coordinate reference system", whereas IERS uses

4510-580: The Moon, and satellite laser ranging (SLR) measuring distances to prisms on artificial satellites , are employed. Gravity is measured using gravimeters , of which there are two kinds. First are absolute gravimeter s, based on measuring the acceleration of free fall (e.g., of a reflecting prism in a vacuum tube ). They are used to establish vertical geospatial control or in the field. Second, relative gravimeter s are spring-based and more common. They are used in gravity surveys over large areas — to establish

4592-580: The Ocean Sciences Meeting, which is held in even numbered years. Small, highly focused meetings are offered through the Chapman Conferences. The large numbers and international participation in the Fall Meeting results in a large contribution to greenhouse gases . The 9500 participants in the 2002 meeting traveled an average of 8,000 kilometres (5,000 mi) to attend, producing 1.3 metric tons of carbon dioxide, or one-sixteenth of

4674-605: The United States in the International Union of Geodesy and Geophysics (IUGG), and its first chairman was William Bowie of the United States Coast and Geodetic Survey (USCGS). For more than 50 years, it operated as an unincorporated affiliate of the National Academy of Sciences . On June 29, 1972, AGU was incorporated in the District of Columbia and membership was opened to scientists and students worldwide. The AGU

4756-671: The XVII General Assembly of the International Union of Geodesy and Geophysics ( IUGG ), posited a 6,378,137 m semi-major axis and a 1:298.257 flattening. GRS 80 essentially constitutes the basis for geodetic positioning by the Global Positioning System (GPS) and is thus also in widespread use outside the geodetic community. Numerous systems used for mapping and charting are becoming obsolete as countries increasingly move to global, geocentric reference systems utilizing

4838-409: The average yearly emissions for Americans. The AGU has made some adjustments such as asking shuttle bus drivers to turn off their engines when they are not moving, but 95% of the emissions come from jet fuel . In an unpublished study, David Scott and Lawrence Plug of Dalhousie University estimated that the AGU could reduce emissions by 7.7% if it moved the Fall Meeting to Denver , Colorado. In 2017,

4920-416: The broader public. Members of the AGU who work in politically-controversial fields have come under legal attack. For example, Michael Mann , a Fellow of the AGU and lead author of the original " hockey stick graph " study, faced a legal demand to turn over his private emails from Kenneth Cuccinelli II , at the time the attorney general of the state of Virginia, a conservative Republican who argues that there

5002-414: The coordinate systems associated with a geodetic datum attempted to be geocentric , but with the origin differing from the geocenter by hundreds of meters due to regional deviations in the direction of the plumbline (vertical). These regional geodetic datums, such as ED 50 (European Datum 1950) or NAD 27 (North American Datum 1927), have ellipsoids associated with them that are regional "best fits" to

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5084-471: The figure of the geoid over these areas. The most accurate relative gravimeters are called superconducting gravimeter s, which are sensitive to one-thousandth of one-billionth of Earth-surface gravity. Twenty-some superconducting gravimeters are used worldwide in studying Earth's tides , rotation , interior, oceanic and atmospheric loading, as well as in verifying the Newtonian constant of gravitation . In

5166-799: The first joint JpGU-AGU meeting was held in Chiba, Japan. The meeting was a joint effort between AGU and the Japan Geoscience Union . On occasion the AGU Council issues position statements on matters affecting public policy that are related to geophysics. These include biological evolution , natural hazards , science education and funding, and climate change . The AGU adopted its first position statement on climate change in December 1998. That statement began Atmospheric concentrations of carbon dioxide and other greenhouse gases have substantially increased as

5248-401: The future, gravity and altitude might become measurable using the special-relativistic concept of time dilation as gauged by optical clocks . Geographical latitude and longitude are stated in the units degree, minute of arc, and second of arc. They are angles , not metric measures, and describe the direction of the local normal to the reference ellipsoid of revolution. This direction

5330-412: The geoid and a reference ellipsoid is called geoidal undulation , and it varies globally between ±110 m based on the GRS 80 ellipsoid. A reference ellipsoid, customarily chosen to be the same size (volume) as the geoid, is described by its semi-major axis (equatorial radius) a and flattening f . The quantity f = ⁠ a − b / a ⁠ , where b is the semi-minor axis (polar radius),

5412-399: The global scale, or engineering geodesy ( Ingenieurgeodäsie ) that includes surveying — measuring parts or regions of Earth. For the longest time, geodesy was the science of measuring and understanding Earth's geometric shape, orientation in space, and gravitational field; however, geodetic science and operations are applied to other astronomical bodies in our Solar System also. To

5494-430: The height of a point above the reference ellipsoid . Satellite positioning receivers typically provide ellipsoidal heights unless fitted with special conversion software based on a model of the geoid. Because coordinates and heights of geodetic points always get obtained within a system that itself was constructed based on real-world observations, geodesists introduced the concept of a "geodetic datum" (plural datums ):

5576-493: The interdisciplinary and international fields within the Earth and space sciences. The geophysical sciences involve four fundamental areas: atmospheric and ocean sciences ; solid-Earth sciences ; hydrologic sciences ; and space sciences . The organization's headquarters is located on Florida Avenue in Washington, D.C. The AGU was established in December 1919 by the National Research Council (NRC) to represent

5658-405: The inverse problem, the azimuths differ going between the two end points along the arc of the connecting great circle . The general solution is called the geodesic for the surface considered, and the differential equations for the geodesic are solvable numerically. On the ellipsoid of revolution, geodesics are expressible in terms of elliptic integrals, which are usually evaluated in terms of

5740-406: The journal code (GL), and an article number (014304). This new system was met with complaints from libraries and scientists. The article numbers provided no clue for libraries to find an article in printed versions, and even scientific databases were not set up to handle DOIs. AGU officials claimed that the problems were a temporary cost of being a frontrunner, but did retroactively assign each article

5822-634: The journals have high impact factors , with Paleoceanography having the highest within paleontology and Reviews of Geophysics the second highest within geochemistry and geophysics as of 2010. AGU has also been publishing books for more than 85 years. AGU has also partnered with societies to publish: AGU co-published (along with the AMS and the AAG) its first electronic journal, Earth Interactions , in 1997. It started its own electronic journal, Geochemistry, Geophysics , Geosystems , in December 1999. It made

5904-622: The meeting. Abramoff was fired by Oak Ridge in January 2023. In 2014, the AGU accepted 5469 gifts, grants and pledges from individuals and corporations. Of these, the 1919 Society (gifts of over $ 100,000) included ExxonMobil , Integrated Ocean Drilling Program Management International, and Nature's Own . AGU also was found to have many annual events sponsored by corporations, including an annual Student Breakfast (supported by ExxonMobil) and Amazon Web Services supported research grants and that offer access to its cloud computing resources. In 2015,

5986-803: The membership can be elected each year. The AGU is divided into 25 sections that provide the main structure for managing volunteers, developing leaders and honoring scientists. These sections also reflect the breadth of science within Earth and space science: atmospheric and space electricity ; atmospheric sciences ; biogeosciences ; cryosphere sciences; Earth and planetary surface processes; Earth and space science informatics ; education; geodesy ; geohealth ; geomagnetism ; paleomagnetism and electromagnetism ; hydrology ; mineral and rock physics ; natural hazards ; near surface geophysics ; nonlinear geophysics ; ocean sciences ; paleoceanography ; planetary sciences ; seismology ; societal impacts and policy sciences ; space physics and aeronomy ; study of

6068-738: The mitigation of human induced climate change and/or the adaptation to it. The adopted position statement was backed up by a detailed supporting document. The AGU position statement has undergone several revisions, most recently revised and reaffirmed in 2012. In 2014, AGU developed the Sharing Science program to provide scientists with the skills and tools that they need to communicate science with any audience. The program offers resources, workshops, hands-on support, and opportunities to help scientists more effectively communicate with broader audiences about Earth and space science. Audiences range from journalists, educators and students, policy makers, and

6150-496: The more economical use of GPS instruments for height determination requires precise knowledge of the figure of the geoid , as GPS only gives heights above the GRS80 reference ellipsoid. As geoid determination improves, one may expect that the use of GPS in height determination shall increase, too. The theodolite is an instrument used to measure horizontal and vertical (relative to the local vertical) angles to target points. In addition,

6232-507: The plane for one's current location, in which case the x -axis will point to the local north. More formally, such coordinates can be obtained from 3D coordinates using the artifice of a map projection . It is impossible to map the curved surface of Earth onto a flat map surface without deformation. The compromise most often chosen — called a conformal projection — preserves angles and length ratios so that small circles get mapped as small circles and small squares as squares. An example of such

6314-422: The sky to a traveler headed South. In English , geodesy refers to the science of measuring and representing geospatial information , while geomatics encompasses practical applications of geodesy on local and regional scales, including surveying . In German , geodesy can refer to either higher geodesy ( höhere Geodäsie or Erdmessung , literally "geomensuration") — concerned with measuring Earth on

6396-455: The very word geodesy comes from the Ancient Greek word γεωδαισία or geodaisia (literally, "division of Earth"). Early ideas about the figure of the Earth held the Earth to be flat and the heavens a physical dome spanning over it. Two early arguments for a spherical Earth were that lunar eclipses appear to an observer as circular shadows and that Polaris appears lower and lower in

6478-717: Was a serious lapse of judgement. He resigned from the task force on February 16, 2012, and was replaced by Linda Gundersen, director of the Office of Science Quality and Integrity at the United States Geological Survey (USGS). In 2017, AGU adopted and updated ethics policy, called the AGU Scientific Integrity and Professional Ethics. Among other updates, the policy updated its definitions of what counts as scientific misconduct to include harassment , bullying , and discrimination. The change came, in part, as

6560-403: Was established by the AGU in 2013 to recognize the groundbreaking contributions of individuals whose achievements extend beyond the scope of traditional scientific honors. The award is annually given to between one and five individuals with notable achievements in societal impact, service to the Earth and space community, scientific leadership, and promotion of talent/career pool. Ambassador Award

6642-617: Was intended to promote "pure" geophysics; exploration geophysics has its own society, the Society of Exploration Geophysicists . In a March 1919 report by a committee chaired by Robert S. Woodward of the Carnegie Institution , geophysics was defined as a collection of "borderlands" (closely related, mutually dependent subjects): astronomy , geodesy , geology, meteorology , oceanography , seismology , terrestrial magnetism , terrestrial electricity , tides , and volcanology . The AGU

6724-449: Was organized under seven sections: Geodesy , Seismology, Meteorology , Terrestrial magnetism and electricity, Oceanography , Volcanology , and Geophysical chemistry. Hydrology was added in 1930 and Tectonophysics in 1940. In suggesting the latter name, Norman Bowen evoked a familiar theme: to "designate this new borderline field between geophysics , physics and geology for the solution of problems of tectonics." The first meeting of

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