Saturday, October 14, 2017

California's Firestorm

Last winter, when heavy snows fell across the Sierra Nevada and soaking rains caused flooding in the lowlands, one might have concluded that California's multi-year drought had finally come to an end.  Indeed, the drought-severity map improved significantly and concerns about the water supply for cities and agriculture were temporarily ignored.  Then came the dry season.

New vegetation growth, fueled by the copious winter precipitation, brought greenery to the semi-arid landscape.  As summer progressed, however, the relentless sun and dry air took a toll on this plant fuel and, combined with an abundant supply of dry timber from years of drought and fire suppression, the stage was set for an October inferno.  Low humidity, typical in early autumn, and strong offshore winds, triggered by high pressure over the Great Basin, have also been major factors in both the intensity and speed of the deadly wildfires.

Those who live in semi-arid regions (including the Colorado Front Range) know that periods of heavy precipitation are but temporary reprieves for a landscape that has long been shaped and renewed by wildfire.  The dry air and abundant sunshine offer an attractive setting for an outdoors lifestyle but come with a risk that is currently all-too-evident in the wine country of Northern California.