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

84 Scopus citations

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
DOIs
StatePublished - Aug 1998

ASJC Scopus subject areas

  • Ocean Engineering
  • Atmospheric Science

Fingerprint Dive into the research topics of 'Empirical orthogonal function analysis of ocean surface currents using complex and real-vector methods'. Together they form a unique fingerprint.

  • Cite this