(Photo by Mark Boster / Los Angeles Times)
From the time of the Tapias, the owners of Rancho Malibu recognized that the region’s extraordinary fire hazard was shaped, in large part, by the uncanny alignment of its coastal canyons with the annual fire winds from the north: the notorious Santa Anas, which blow primarily between Labor Day and Thanksgiving, just before the first rains. Born from high-pressure areas over the Great Basin, Santa Anas become hot and dry as they descend avalanchelike into Southern California. The San Fernando Valley acts as a giant bellows, sometimes fanning the winds to hurricane velocity as they roar seaward through the narrow canyons and rugged defiles of the Santa Monicas. Add a spark to the thick vegetation (frequently above 40 tons per acre in the Malibu area) on such an occasion, and an uncontrollable wildfire will result.