Computational geophysics

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Computational geophysics is the field of study that uses any type of numerical computations to generate and analyze models of complex geophysical systems. It can be considered an extension, or sub-field, of both computational physics and geophysics. In recent years, computational power, data availability, and modelling capabilities have all improved exponentially, making computational geophysics a more populated discipline. [1] Due to the large computational size of many geophysical problems, high-performance computing can be required to handle analysis. [2] Modeling applications of computational geophysics include atmospheric modelling, oceanic modelling, general circulation models, and geological modelling. In addition to modelling, some problems in remote sensing fall within the scope of computational geophysics such as tomography, inverse problems, and 3D reconstruction.

Contents

Geophysical models

The generation of geophysical models are a key component of computational geophysics. Geophysical models are defined as "physical-mathematical descriptions of temporal and/or spatial changes in important geological variables, as derived from accepted laws, theories, and empirical relationships." [3]  Geophysical models are frequently used by researchers in all disciplines of environmental science.

In climate science, atmospheric, oceanic, and general circulation models are a crucial standby for researchers. Although remote sensing has been steadily providing more and more in-situ measurements of geophysical variables, nothing comes close to the temporal and geospatial resolution of data provided by models. Although data can be subject to accuracy issues due to the extrapolation techniques used, the usage of modeled data is a commonly accepted practice in climate and meteorological sciences. Oftentimes, these models will be used in concert with in-situ measurements.

A few well-known models are

  1. NCEP/NCAR Reanalysis Project, an atmospheric model [4]
  2. Global Forecast System, a numerical weather prediction model [5]
  3. HYCOM, a general ocean circulation model [6]

Geological system models are frequently used in research, but have less public data availability than climatic and meteorological models. There is a wide range of software available that allows for geomodelling.

Remote sensing

The United States Geological Survey (USGS) defines remote sensing as the measurement of some property by transmitting some type of radiation at a distance, and measuring the emitted and reflected radiation. Remote sensing can involve satellites, cameras, and sound wave emission. [7] Remote sensing is inherently a type of indirect measurement, meaning that some type of computation must be completed in order to obtain a measurement of the property of interest. For some applications, these computations can be highly complex. In addition, the analysis of these data products can be classified as computational geophysics.

Programs of study

In Canada, computational geophysics is offered as a university major in the form of a BSc (Hon.) with co-op at Carleton University. [8]

Elsewhere, Rice University has a Center for Computational Geophysics, [9] while Princeton University, [10]  the University of Texas, [1]  and California Institute of Technology [11] have similar research centers. Experts, laboratories, projects, internships, undergraduate programs, graduate programs and/or facilities in the program exist at the University of Queensland, Wyoming University, Boston University, Stanford University, Uppsala University, Kansas State University, Kingston University, Australian National University, University of California, San Diego, University of Washington, ETH Zurich, University of Sydney, Appalachian State University, University of Minnesota, University of Tasmania, Bahria University, Boise State University, University of Michigan, University of Oulu, University of Utah, and others.

Laboratories

Federal organizations that study or apply computational geophysics include

  1. Earth System Research Laboratories at NOAA [12]
  2. Earth Sciences Division at NASA [13]

Related Research Articles

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References

  1. 1 2 "Computational Geosciences | Jackson School of Geosciences | The University of Texas at Austin". www.jsg.utexas.edu. Retrieved 2019-11-20.
  2. "Advanced Research Computing (ARC)". www.usgs.gov. Retrieved 2019-11-20.
  3. Slingerland, Rudy. (2011). Mathematical modeling of Earth's dynamical systems : a primer. Princeton University Press. ISBN   9780691145136. OCLC   857968920.
  4. "ESRL : PSD : NCEP/NCAR Reanalysis 1". www.esrl.noaa.gov. Retrieved 2019-11-20.
  5. "Global Forecast System (GFS) | National Centers for Environmental Information (NCEI) formerly known as National Climatic Data Center (NCDC)". www.ncdc.noaa.gov. Retrieved 2019-11-20.
  6. "HYCOM". www.hycom.org. Retrieved 2019-11-20.
  7. "What is remote sensing and what is it used for?". www.usgs.gov. Retrieved 2019-11-20.
  8. "Carleton University Undergraduate Calendar 2005-2006 Web Edition". www3.carleton.ca. Retrieved 2019-11-20.
  9. "Rice Earth, Environmental & Planetary Sciences | Earth Science Center for Computing (ESCC)" . Retrieved 2019-11-20.
  10. "Home Page | Theoretical & Computational Seismology". tromp.princeton.edu. Retrieved 2019-11-20.
  11. "Computational Geophysics - Caltech Seismological Laboratory". seismolab.caltech.edu. Retrieved 2019-11-20.
  12. "NOAA Earth System Research Laboratories". www.esrl.noaa.gov. Retrieved 2019-11-20.
  13. Kovo, Yael (2016-08-09). "Earth Sciences Division". NASA. Archived from the original on 2016-08-21. Retrieved 2019-11-20.

See also