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7 questions & answers about California's wildfires

Blog Post created by luciandeaton Employee on Nov 19, 2018

[Update: Nov. 21, 10:30 a.m. EST - The Camp Fire now stands at 153,336 acres, with 80% containment. It has destroyed 13,503 residences and 514 commercial structures. 81 fatalities are now reported. CALFire shares that, “Moderate to heavy rain is forecasted over the fire area from this morning into Saturday.” The Woolsey Fire remains unchanged at 98,949 acres, with 98% containment. Learn more below and see links for updated information.]


The Camp Fire in Northern California's Butte County and the Woolsey Fire in southern Los Angeles and Ventura Counties are breaking records every day.  A good source to follow breaking news is the LA Times Live Feed and on the Twitter hashtags, #Woolseyfire and #Campfire.  NFPA wants to share some information below to help put these fires in context and answer some common questions.   

 

What is the wildfire's size?

While even a small wildfire can put many residents at risk, the sheer size of the wildfires in California can be hard to imagine.  As of Monday morning, the two main fires – the Camp Fire and the Woolsey Fire – had burned a cumulative total of 247,949 acres.  For context, converted to square miles, that is the size of Dallas, Texas.  

 

Is a "Wall of Flame" burning down cities?

As the media illustrates the impacts of wildfire, you may hear about a "wall of flame" pushing through a city and destroying all in its path.  If this is true, why do we often see green trees remain around burnt out structures?  This is because blowing embers, and not a wall of flame from a wildfire, are landing on vulnerable areas of structures to cause home loss.  Watch this video from NFPA's Firewise USA® Program to learn more about the impacts of embers on structures.     

 

Why have there been so many fatalities?

As of Monday morning, 77 fatalities have been reported from the Camp Fire, with an additional three fatalities from the Woolsey Fire.  The LA Times is sharing bios on those who have passed away.  You'll quickly see that the elderly and disabled comprise a majority of those lost.  This is because receiving alert information and evacuating can be a challenge to different demographic groups. 
     


As the death toll rises, the list of those missing topped 1200 over the weekend.  While we will unfortunately learn of more fatalities, the current high missing list is a raw count and contains many discrepancies.   Learn more about the challenge of counting the missing here. 

Why are so many homes burning?

The figures on structural loss from these fires can be staggering to comprehend.  As of Monday morning's CALFire incident report, the Camp Fire has destroyed 11,713 residential structures and 472 commercial structures, with the Woolsey Fire claiming 1500 total structures

 

Urban conflagrations – uncontrolled structure-to-structure ignitions – were common 100 years ago, but regulations, safety messaging, and building improvements largely ended this challenge in our urban environments.  Yet, as we have developed into the "wildland urban interface" – where homes interface with natural areas – this challenge has returned.  The focus on risk and proper rebuilding has become more difficult for local politicians and residents alike.  Learn from historic California examples of this challenge as well.  

 

Is home loss inevitable?

No, and NFPA stresses that residents have a positive role to play in reducing their home's risk to wildfire.  This focus can also ensure that the spread of an urban conflagration stops at the first home impacted by blowing embers from a fire.  Once structure-to-structure ignition starts, firefighting resources become overwhelmed, and total loss ensues.  Watch this Firewise USA® video about how residents can reduce this risk. 

 

Why is a wildfire burning at the end of November?

It is not unusual for California to have large fires in the late fall.  This is the peak season for "Santa Ana" winds, which is the local name for dry down slope winds.  In California, they blow from east to west and as they move downhill, they compress due to increased atmospheric pressure, which causes them to be hot and dry.   The result is that vegetation that has been drying for most of the summer become even drier from the desiccating winds.  

 

So if ignitions happen, fire can move very quickly.  These down slope winds have been clocked up to 70 mph at times.  As with "fire seasons" in general, the fall Santa Ana season has become longer.  In 2017, the Thomas fire in Southern California was actively burning in December.

 

What about climate change and forest health?

Regardless of the cause of climate change, California has been in a multi-year drought and its "fire season" has become longer, both in the spring and fall.  There has been a lot in the news as well about the role that forest thinning would have on reducing the fire risk.  Fire Ecology Historian Steve Pyne wrote a great piece explaining forest health and debunks some of the recent politicized arguments.  

 

As these fires continue, our thoughts continue to be with those affected and those who have lost loved ones.  

 

Tom Welle contributed to this blog

Photo Credit:  NIFC Photo Library, pulled 19 Nov 2018

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