Interaction between a wildfire and the sea-breeze front
Abstract
Florida experiences sea breezes, lake breezes, and bay breezes almost every day during the year, and there are frequently complex interactions between many of these breezes. Given the often-rapid changes in temperature, humidity, and wind speed that accompany these breezes, most wildfires and prescribed fires in Florida are affected in some way by their interaction with these circulations. In this paper, we explore the interaction between sea breezes and wildland fires from both an observational and an idealized modeling perspective. The progression of the sea-breeze front and its interaction with the smoke plume from a 26,000 acre wildfire are tracked using a variety of data sources including surface and upper-air observations as well as NEXRAD radar imagery. Idealized numerical simulations of a thermally buoyant plume interacting with a density current are performed in an effort to enhance our understanding of the dynamics of the interaction between sea breeze circulations and the convective column of the fire. Our observational analysis and idealized modeling results suggest that the arrival of a sea breeze front induces a temporary, but significant, increase in fire intensity. This intensification precedes the arrival of the sea-breeze front at the location of the fire, such that the fire intensity is at a maximum at the time of, and slightly after, the passage of the front, and decreases gradually thereafter as cooler and moister air behind the front arrive.