Forecasting Tropical Cyclone Recurvature Using an Empirical Orthogonal Function Representation of the Synoptic Forcing.
Abstract
Empirical Orthogonal Function (EOF) representation of the synoptic forcing is combined with past meridional and zonal displacements (persistence) to forecast tropical cyclone recurvature at 36, 54 and 72 h. Recurvature is defined following Leftwich (1978, 1982): Recurvature is a net displacement northward of 315 luring the forecast period or the attaining of northeastward motion during the 12 hours prior to the end of the forecast period. The combination of persistence and EOF coefficients consistently out-performed the individual methods for forecasting recurvature in both the dependent and independent data samples. Evaluation stores were the Brier p-score, the Heidke skill score and percent correctly forecast. Seven forecast aids used by Joint Typhoon Warning Center (JTWC) Guam, were tested for ability to forecast tropical cyclone recurvature at 24, 48 and 72 h. Using the skill scores described above for the 1979-81 typhoon seasons, performance indicates large annual variations of skill between the models. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1982
- Accession Number
- ADA126711
Entities
People
- Thomas D. Lage
Organizations
- Naval Postgraduate School