The Sundowner Winds Experiment (SWEX) in Santa Barbara, California Advancing Understanding and Predictability of Downslope Windstorms in Coastal Environments

Authors

Leila M.V. Carvalho, University of California, Santa Barbara
Gert Jan Duine, University of California, Santa Barbara
Craig Clements, San Jose State UniversityFollow
F. J. Stephan
De Wekker, University of Virginia
Harindra J.S. Fernando, University of Notre Dame
David R. Fitzjarrald, State University of New York Albany
Robert G. Fovell, State University of New York Albany
Charles Jones, University of California, Santa Barbara
Zhien Wang, Stony Brook University
Loren White, Jackson State University
Anthony Bucholtz, Naval Postgraduate School
Matthew J. Brewer, State University of New York Albany
William Brown, National Center for Atmospheric Research
Matt Burkhart, University of Wyoming
Edward Creegan, University of Notre Dame
Min Deng, Brookhaven National Laboratory
Marian de Orla-Barile, University of California, Santa Barbara
David Emmitt, Simpson Weather Associates

Publication Date

3-1-2024

Document Type

Article

Publication Title

Bulletin of the American Meteorological Society

Volume

105

Issue

3

DOI

10.1175/BAMS-D-22-0171.1

First Page

E532

Last Page

E558

Abstract

Coastal Santa Barbara is among the most exposed communities to wildfire hazards in Southern California. Downslope, dry, and gusty windstorms are frequently observed on the south-facing slopes of the Santa Ynez Mountains that separate the Pacific Ocean from the Santa Ynez valley. These winds, known as “Sundowners,” peak after sunset and are strong throughout the night and early morning. The Sundowner Winds Experiment (SWEX) was a field campaign funded by the National Science Foundation that took place in Santa Barbara, California, between 1 April and 15 May 2022. It was a collaborative effort of 10 institutions to advance understanding and predictability of Sundowners, while providing rich datasets for developing new theories of downslope windstorms in coastal environments with similar geographic and climatic characteristics. Sundowner spatiotemporal characteristics are controlled by complex interactions among atmospheric processes occurring upstream (Santa Ynez valley), and downstream due to the influence of a cool and stable marine boundary layer. SWEX was designed to enhance spatial measurements to resolve local circulations and vertical structure from the surface to the midtroposphere and from the Santa Barbara Channel to the Santa Ynez valley. This article discusses how SWEX brought cutting-edge science and the strengths of multiple ground-based and mobile instrument platforms to bear on this important problem. Among them are flux towers, mobile and stationary lidars, wind profilers, ceilometers, radiosondes, and an aircraft equipped with three lidars and a dropsonde system. The unique features observed during SWEX using this network of sophisticated instruments are discussed here.

Keywords

Boundary layer, Downslope winds, Lidar observations, Mesoscale processes, Mountain meteorology, Profilers, atmospheric

Department

Meteorology and Climate Science

Recommended Citation

Leila M.V. Carvalho, Gert Jan Duine, Craig Clements, F. J. Stephan, De Wekker, Harindra J.S. Fernando, David R. Fitzjarrald, Robert G. Fovell, Charles Jones, Zhien Wang, Loren White, Anthony Bucholtz, Matthew J. Brewer, William Brown, Matt Burkhart, Edward Creegan, Min Deng, Marian de Orla-Barile, and David Emmitt. "The Sundowner Winds Experiment (SWEX) in Santa Barbara, California Advancing Understanding and Predictability of Downslope Windstorms in Coastal Environments" Bulletin of the American Meteorological Society (2024): E532-E558. https://doi.org/10.1175/BAMS-D-22-0171.1