Applications of Wind Empirical Orthogonal Functions in Tropical Cyclone Motion Studies.
Abstract
An empirical orthogonal function (EOF) analysis is used to represent environmental wind fields associated with selected western North Pacific tropical cyclones from 1979-1983. Composite synoptic patterns within five past-motion categories of cyclones are studied using 5, 10, 20 and 35 EOF modes. Significant differences in the composite fields are found between categories, which suggests that the wind EOFs are capable of representing synoptic patterns associated with tropical cyclone motion. Regression equations are developed to post-process the forecast track of the One-way Tropical Cyclone Model (OTCM). The predictors for the regression analysis include the EOF coefficients, past motion, storm position, date, intensity, backward extrapolation and forward track displacements. For the dependent sample, the mean 72-h track forecast error for the modified OTCM is 383 km, which represents a 210 km improvement relative to the unmodified OTCM. Thus, the regression scheme has great potential for operational application. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1985
- Accession Number
- ADA164170
Entities
People
- Thomas B. Schott
Organizations
- Naval Postgraduate School