Sunday, November 8, 2020

A fire season like no other, or a taste of what's to come?

The charred remains of a lightning strike in the Ansel Adams Wilderness
 

As I write these words the first snowfall of the season is settling in over the Sierra Nevada and we can finally put the fire season in Northern California to bed.  SoCal... it seems that fire season is year round now, so no rest for the weary there.  In this season of counting - counting votes, counting coronavirus cases - it's time to count up the costs.  By all measures, this was a particularly intense fire season. According to the Center for Disaster Philanthropy, 4.2 million acres burned in California this year (more that twice the previous record), damaging over 10,000 structures and claiming at least 31 lives.  The financial costs of these fires is hard to fully quantify, but estimates in the tens of billions of dollars are common.  

On a far less consequential note, of the 92 hikes currently described on his blog 12 have been burned by or were very close to major fires. This is the first year I can remember more than one or two hikes being affected by fire.  Not all fires are equal, with some being low intensity burns in in fire adapted areas, and others are extreme fire events, burning forests damaged by years of stress down to nothing.  All these hikes dramatically affected in one summer is a good reminder to always check local park and forest service resources before hitting the trails. Even recent trail descriptions can rapidly become out of date.  I'll put a notice on those blog entries, but each hike will have its own timeline for recovery.

For me the big question hanging from the 2020 fire season will be, was this a once in a lifetime summer, or a harbinger of the new normal?  There are two competing forces driving this question.  

 On the one side, we've mismanaged fire in the forest for around 100 years.  A fire suppressed is a fire delayed and a fire delayed is a bigger, hotter, more dangerous fire.  We built up a huge reservoir of fuel on the land, arming a bomb under our own feet.  Thankfully there has been a big change in the philosophy of fire management in our forest and fire fighting agencies, with a growing understanding that it's better to have as many small, low intensity fires as possible.  It's still very much a work in progress, but we're also finally starting to work out how we can include indigenous California tribes in our wildfire management.  On top of the change in attitude, all the huge fires in the past few years have really depleted the growing fuel backlog.  A cursory look at the lands burned in the past 20 years (and that doesn't even include 2020) shows that we're pretty far along in the turning over all that built up fuel.  If all else were equal, I'd be optimistic that we're at or near peak fire.

But all else is not equal.  Climate change likely means longer, drier, summers and more prolonged years of drought.  Already the stress on some California forests has made them more vulnerable to an invasive bark beetle infestation that has degraded large areas of forestland at mid altitude elevations.  The habitable zone for large conifer species is slowly creeping northward and up-slope.  I fear as the healthy forests retreat they're going to leave a trail of parched dead-fall ripe for explosive, dangerous fire events.  It was exactly this sort of situation that created the terrifyingly fast moving Creek Fire this year, the fire that set up a dramatic helicopter rescue of trapped hikers and boaters at Mammoth Pool and pumped so much ash into the air that it cast an eerie orange pall over San Fransisco.  Climate change seems to mean more fires like that, which is an unsettling prospect indeed. 


Hikes affected by major fires this year

Bay Area

Sunol Regional Widerness

Murietta Falls

Mariposa Point

Oat Hill Mine Trail 


Plumas National Forest

Grass Valley Bald Mountain

Feather Falls Loop

 

Sierra National Forest

Lillian Lake Loop

 

No comments:

Post a Comment