Mesoscale Eddy Formation and Shock Features Associated with a Coastally Trapped Disturbance
Abstract
Synoptic maps for 28-29 August 2002 indicate typical near-surface northerly flow along coastal California, while Goes-10 animated satellite imagery from this period show a stratuscapped, coastally trapped disturbance (CTD) propagating northward against the prevailing flow. A pronounced hydraulic-jump-like ("shock") feature develops in the cloud field south of Cape Mendocino (CM) and angles linearly away from the coast. Over the next ~6 hours both the CTD and the shock feature move northward and, as they approach the Cape, the leading edge of the CTD clouds roll-up into a visually striking cyclonic mesoscale eddy-with the shock feature being wrapped into the eddy. The CTD rather abruptly stalls and fails to round CM. Further, a second cyclonic mesoscale eddy is observed to form SW of Point Arena. Using a mesoscale model, many of the observed features of this case are forecast, including: (a) the cloud-filled, northward propagating CTD; (b) the development, linear structure, and orientation of the oblique shock feature; (c) the CTD rounds Point Arena, but fails to round CM; and (d) the formation of cyclonic mesoscale eddies near CM and Point Arena. The model fidelity permits us to analyze the dynamics associated with the shock feature and eddy formation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2003
- Accession Number
- ADA498758
Entities
People
- Stephen D. Burk
- William T. Thompson
Organizations
- United States Naval Research Laboratory