Empirical orthogonal function analysis of ocean surface currents using complex and real-vector methods

James M. Kaihatu, Robert A. Handler, George O. Marmorino, Lynn K Shay

Research output: Contribution to journalArticle

78 Citations (Scopus)

Abstract

Empirical orthogonal function (EOF) analysis has been widely used in meteorology and oceanography to extract dominant modes of behavior in scalar and vector datasets. For analysis of two-dimensional vector fields, such as surface winds or currents, use of the complex EOF method has become widespread. In the present paper, this method is compared with a real-vector EOF method that apparently has previously been unused for current or wind fields in oceanography or meteorology. It is shown that these two methods differ primarily with respect to the concept of optimal representation. Further, the real-vector analysis can easily be extended to three-dimensional vector fields, whereas the complex method cannot. To illustrate the differences between approaches, both methods are applied to Ocean Surface Current Radar data collected off Cape Hatteras, North Carolina, in June and July 1993. For this dataset, while the complex analysis "converges" in fewer modes, the real analysis is better able to isolate flows with wide cross-shelf structures such as tides.

Original languageEnglish (US)
Pages (from-to)927-941
Number of pages15
JournalJournal of Atmospheric and Oceanic Technology
Volume15
Issue number4
StatePublished - Aug 1998

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Orthogonal functions
sea surface
Oceanography
Meteorology
oceanography
meteorology
Tides
wind field
surface wind
Radar
empirical orthogonal function analysis
method
tide
radar
analysis

ASJC Scopus subject areas

  • Atmospheric Science
  • Ocean Engineering

Cite this

Empirical orthogonal function analysis of ocean surface currents using complex and real-vector methods. / Kaihatu, James M.; Handler, Robert A.; Marmorino, George O.; Shay, Lynn K.

In: Journal of Atmospheric and Oceanic Technology, Vol. 15, No. 4, 08.1998, p. 927-941.

Research output: Contribution to journalArticle

Kaihatu, James M. ; Handler, Robert A. ; Marmorino, George O. ; Shay, Lynn K. / Empirical orthogonal function analysis of ocean surface currents using complex and real-vector methods. In: Journal of Atmospheric and Oceanic Technology. 1998 ; Vol. 15, No. 4. pp. 927-941.
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