Geomorphometrics

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Geomorphometrics is the discipline based on the computational measures of the geometry, topography and shape of the Earth's horizons, and their temporal change. (Turner 2006)

Overview[edit]

The term ‘’geomorphometrics’’ refers to:

History and Origins[edit]

Geomorphometrics deals with the quantification of the geometry, topography, and physical landforms of the Earths horizons, over time (Turner, 2006), and branches out from the disciplines of geomorphology, geomatics and geomorphometry. Geomorphology has a long history as a concept and area of study, with geomorphometry being one of the oldest related disciplines (Schmidt, 2005). Geomatics is a more recently evolved sub-discipline, and even more recent is the concept of geomorphometrics. This has only recently been developed since the availability of more flexible and capable geographic information system (GIS) packages, as well as higher resolution Digital Elevation Model (DEM) (Turner, 2007). It is a response to the development of this GIS technology to gather and process DEM data (e.g. remote sensing, the Landsat program and photogrammetry).

How geomorphometrics works[edit]

With a topographic landscape the question arises as to where a feature is and also as to how accurately it can be classified or identified. Geomorphometrics involves deriving values from the DEM data that infer geomorphological features, such as whether relative local values describe peaks, passes, pits, planes, channels and ridges. Due to limitations from resolution, axis-orientation, and object-definitions the derived spatial data may yield meaning with subjective observation or parameterisation, or alternatively processed as fuzzy data to handle the varying contributing errors more quantitatively – for example as a 70% overall chance of a point representing the peak of a mountain given the available data, rather than an educated guess to deal with the uncertainty (Fisher et al., 2004).

Applications[edit]

Quantitative surface analysis through geomorphometrics provides the tools for scientists and managers interested in land management (Albani et al., 2004). Applications areas include:

Geomorphometricians[edit]

As a relatively new and unknown branch of GIS the topic of geomorphometrics has few ‘famous’ pioneer figures as is the case with other fields such as hydrology (Robert Horton) or geomorphology (Roger Chorley). In the past geomorphometrics have been used in a wide range of studies (including some high profile geomorphology papers by academics such as Evans, Leopold and Wolman (Chorley, 1972; Klimanek, 2006) but it is only recently that GIS practitioners have begun to integrate it within their work. Nonetheless it is becoming increasingly used by researchers such as Andy Turner and Joseph Wood.

International Organisations[edit]

Large institutions are increasingly developing GIS-based geomorphometric applications, one example being the creation of a Java-based software package for geomorphometrics in association with the University of Leeds. Example output can be accessed from the external links section.

Education in geomorphometrics (institutions)[edit]

Academic institutions are increasingly devoting more resources into geomorphometrics training and specific courses although these are still currently limited to a few universities and training centres. The most accessible at present include online geomorphometrics resource library in conjunction with the University of Leeds and lectures and practicals delivered as part of wider GIS modules, the most comprehensive at present offered at the University of British Columbia (overseen by Brian Klinkenberg) and at Dalhousie University.

Geomorphometry/geomorphometrics software[edit]

The following computer software has specialized terrain analysis modules or extensions (listed in alphabetical order):

See also[edit]

The topic of geomorphometrics is a close affiliate of a number of other fields such as:

External links[edit]

  • [1] - University of Leeds - school of Geography, geomorphometrics home page
  • [2] - example of Leeds University-developed geomorphometrics output with processing- and resolution-based parameters
  • [3] - University of British Columbia - department of Geography
  • [4] - Dalhousie University - geomorphology and landscape evolution module

References[edit]

  • Albani, M., Klinkenberg, B. Anderson, D. W. & Kimmins, J. P. (2004) The choice of window size in approximating topographic surfaces from Digital Elevation Models. International Journal of Geographical Information Science, 18 (6); pp577-593.
  • Chorley,R.J. 1972. Spatial Analysis in Geomorphology. Methuen and Co Ltd, UK.
  • Fisher, P, Wood, J. & Cheng, T. (2004) Where is Helvellyn? Fuzziness of multi-scale landscape morphometry. Transactions of the Institute of British Geographers, 29; pp106-128.
  • Klimanek,M. 2006. Optimisation of digital terrain model for its application in forestry, Journal of Forest Science, 52 (5); pp 233-241.
  • Mark,D.M. 1975. Geomorphometric parameters: a review and evaluation, Geographical Annals, 57, (1); pp 165-177.
  • Schmidt, J. & Andrew, R. (2005) Multi-scale landform characterization. Area, 37.3; pp341-350.
  • Turner, A. (2007) Lecture 7: Terrain analysis 3; geomatics, geomorphometrics [online] School of Geography, University of Leeds, UK; [5] Accessed 7 May 2007.
  • Turner, A. (2006) Geomorphometrics: ideas for generation and use. CCG Working Paper, Version 0.3.1 [online] Centre for Computational Geography, University of Leeds, UK; [6] Accessed 7 May 2007.