‘LA wildfires could continue unless weather changes - expert

Strong winds threaten to ignite new wildfires in Los Angeles, local reports suggest. Dr Olivia Haas, a wildfires expert at the University of Reading, explains what caused the devastating fires, and what factors may cause them to continue. 

Dr Olivia Haas said: "There are three key factors that have contributed to the extent and damage of these wildfires: dry and windy climate, build-up of flammable vegetation and flammable materials in houses. Firstly, a combination of extremely dry conditions and strong winds have created highly fire-prone weather. These winds, known as the Santa Ana winds, will continue to cause problems because they can rapidly push flames and embers across large areas. What's particularly concerning is how these winds might interact with the local geography - when they funnel through canyons and valleys, they can become even more powerful. This kind of weather pattern often creates a cycle where fires can easily spread and reignite, even in areas that have already burned. Until these wind conditions improve, which might take several more days, the situation could remain very challenging for firefighters. One of the biggest challenges firefighters face is that even after they extinguish visible flames, the ground underneath can remain very hot, potentially allowing fires to reignite when conditions are right. This is especially concerning when combined with strong winds. These types of large-scale fires might continue for quite some time unless there's a significant change in weather conditions or we get some substantial rainfall.

“However, the wildfires we are seeing are also a consequence of broader conditions, namely urban planning and the expansion of settlements into the wildland-urban interface. The natural vegetation in Southern California is prone to and promotes wildfires and is also becoming increasingly dry. A policy of fire suppression across California also means that there has also been a build-up of this type of vegetation, leading to higher fuel loads. The wildfires originated in the Pacific Palisades area, which is situated in the wildland-urban interface. As urban settlements are built closer and closer to this natural vegetation, the risk of wildfires spreading into urban areas increases. Finally, many settlements are built with flammable materials such as wood, which further increases the risk of a wildfire spreading through a neighbourhood. These three factors have created the conditions for this unprecedented fire event. To prevent such an event from occurring again, there is an urgent need for better fire governance in the area. Wildfire risk must be considered in urban planning in California and increased monitoring and fire management in the wildland-urban interface is also needed."