BBC :
It was terrible timing. In the late morning of Tuesday 6 January, a “life-threatening and destructive” windstorm was heading for the northern suburbs of Los Angeles. The local office of the US National Weather Service published a strongly worded alert at roughly 10:30am local time. At almost that exact moment, a fire erupted in the Palisades neighbourhood of LA.
“The fire was able to get started, get a foothold, and then the wind came in and pushed it really, really hard,” says Ellie Graeden, co-chief executive of RedZone Analytics, which makes wildfire modelling products for the insurance industry. “This is really as bad as it can get.”
The fire exploded, followed by other wildfires in nearby areas. Thousands of homes and other buildings have been razed. Sunset Boulevard is in ruins. At the time of writing, LA’s fires have killed at least 10 people. Officials have ordered nearly 180,000 people to evacuate.
The fires now rank as the most destructive in LA’s history, with some estimates of the damage put at between $52bn-57bn (£42bn-£46bn).
We still don’t know why they started, however. It might have been a lightning strike, downed power lines, a carelessly discarded cigarette. There could be a more nefarious reason, arson. Most wildfires are caused by humans.
But as the LA authorities begin to piece together what initially sparked the blazes, the speed with which those first flames became raging, rapidly spreading infernos is symptomatic of something happening far more widely.
In this case, a confluence of environmental conditions came together with devastating timing. A combination of long-term drought and heavy rainfall in the days before provided the fuel, while powerful – and at times hurricane-force – winds fanned the fires into raging infernos.
At the outset, the Santa Ana winds as they are known – strong and gusty winds that blow from inland towards the coast – reached speeds of 80mph (129km/h), supercharging the inferno.
Disastrously, the high winds prevented some firefighting helicopters and planes from taking to the skies in order to dump water on the burning areas.
“Without that air support, we’re basically playing whack-a-mole to prevent losses at specific points,” says Ms Graeden.
These conditions come against the backdrop of climate change, which is not only increasing the risk of wildfires around the world, but also making them particularly explosive. This is when relatively small blazes rapidly “blow up” so suddenly and with such ferocity that they become difficult to control.
In California, the risk of such extremely fast-growing fires has increased by an estimated 25% due to human-caused climate change, according to some models.
Rising temperatures and prolonged periods of drought are stripping vegetation and dead plant material of their moisture, meaning when a fire does start, there can be no stopping it.
Matt Jones, an Earth system scientist at the University of East Anglia, who studies the impact of climate change on wildfires, notes that, in 2022 and 2023, LA received extraordinary amounts of rain. Some 52.46in (133cm) of precipitation hit downtown LA during this period, which was nearly a record.
