Skip to main content
Article
Kinematic structure of a wildland fire plume observed by Doppler lidar
Journal of Geophysical Research: Atmospheres (2013)
  • A. M. Charland, San Jose State University
  • Craig B. Clements, San Jose State University
Abstract
Wildland fires present a challenging environment to make meteorological measurements. Observations in the vicinity of wildland fires are needed to better understand fire-atmosphere interactions and to provide data for the evaluation of coupled fire-atmosphere models. An observational study was conducted during a low-intensity prescribed fire in an area of complex terrain with grass fuels east of San José, California. A ground-based scanning Doppler lidar acquired radial wind velocities and backscatter intensity in and around the fire plume from multiple horizontal and vertical scans. The development of a convergence zone was consistently observed to exist downwind of the plume and was indicated by a decrease in radial velocity of 3–5 m s−1. Divergence calculations made from the lidar radial velocities showed that the magnitude of convergence ranged between −0.06 and −0.08 s−1 downwind of the plumes, while a maximum of −0.14 s−1 occurred within the plume near the fire front. Increased radial velocities were observed at the plume boundary, indicating fire-induced acceleration of the wind into the base of the convection column above the fire front. Thermodynamic measurements made with radiosondes showed the smoke plume had a potential temperature perturbation of 3.0 to 4.4 K and an increase in water vapor mixing ratio of 0.5 to 1.0 g kg−1. Plume heights determined from sequential range height indicator scans provided estimates of vertical velocity between 0.4 and 0.6 m s−1, representing the ambient background vertical velocity as the top of the plume likely reached equilibrium.
Keywords
  • kinematic structure,
  • wildland fire,
  • doppler lidar
Publication Date
2013
DOI
10.1002/jgrd.50308
Publisher Statement
©2013. American Geophysical Union. All Rights Reserved.

This article was published in the Journal of Geophysical Research: Atmospheres, volume 118, issue 8, 2013, and can also be found online at this link: http://dx.doi.org/10.1002/jgrd.50308

SJSU users: use the following link to login and access the article via SJSU databases
Citation Information
A. M. Charland and Craig B. Clements. "Kinematic structure of a wildland fire plume observed by Doppler lidar" Journal of Geophysical Research: Atmospheres Vol. 118 Iss. 8 (2013) p. 3200 - 3212 ISSN: 2169-8996
Available at: http://works.bepress.com/craig_clements/5/