Wildfires in California (screen shot via abc.net.au).

As the California fires continue to rage and over 200,000 homes are evacuated, Trump, Abbott and others can deny it all they want but climate change is to blame, writes Dr Norm Sanders.

THE LAST JOB I had before coming to Australia in 1974, was as an assistant professor of geography at the University of California, Santa Barbara.

(I got fired when my students were accused of burning down the Bank of America Isla Vista branch during an anti-Vietnam war demo.)

I helped establish the first environmental studies course in the U.S. Even then, we taught that the Earth's climate was being affected by human activity. The models weren't as sophisticated as today but the basic concept has remained the same. If you take fossil fuels, which have been collecting over millions of years, out of the ground and burn them all at once, something is going to happen and it definitely won't be good.

Today there was a news item which read: 'UCSB finals Week Postponed, Yang Announces'. 

The reason for this drastic announcement was the Thomas Fire which had started in Ventura County and was now burning relentlessly west to Santa Barbara. Throughout the week, students had petitioned for the university to cancel classes and finals as air quality in the county worsened.

At this writing, more than 210,000 acres had burned and 200,000 people had had to flee their homes. The flames were approaching the eastern edge of Santa Barbara at Montecito where I had lived with my family. Residents have been ordered to evacuate. Some are staying put. 

An old UCSB colleague, Marc McGinnes, sent this message today from his home in Painted Cave in the hills behind the town:

Hi Sue, Hi Norm,

Thank you for your caring thoughts and support!

No doubt about it: there are fire-breathing dragons in the mountains close-by, and their poisonous vapours surround us as we hunker down and do our best to keep our courage up.

We are OK.

Outstanding coverage is at keyt.com.

I see you clearly in mind’s eye, and you make me smile and wave in friendship across the wide waters in between.
May you be wonderfully well!

Marc

Is climate change to blame? California Governor Jerry Brown thinks so. Governor Brown has told the State’s residents to get used to destructive wildfires in winter, declaring them “the new normal”. He said it will take “heroic” efforts in the U.S. and abroad to stem climate change and urged Congress to pay more attention to dealing with natural disasters such as fires, floods and earthquakes. He told network television that Donald Trump did not appreciate that actions such as withdrawing the U.S. from the Paris climate deal might contribute to more such devastating events. 

The California fire season was once largely confined to the hotter months when rain is scarce, but firefighters are coming to realise that climate change is now a year-round threat. It is now official: 2017 is the deadliest and most destructive year on record for wildfires in California. Dry conditions, high temperatures, roaring winds and bone-dry trees and brush are all factors responsible for the devastation. A key factor is wind.

UCLA climate scientist Daniel Swain told KPCC radio:

In terms of these really fast moving destructive and wildfires that tend to be a threat to life and property, there’s almost always some sort of strong winds involved ... Those winds can cause fires to move quickly, to jump over barriers over freeways and jump from house to house and move out of the forest, and out of the dry brush into regions where people actually live.

Neither the destructive fire earlier this year in Santa Rosa or the fire currently rampaging through Ventura County would've spread as quickly without the help of strong, dry winds. In Southern California, we have the Santa Ana Winds to blame and, right now, we're living through an event that's both stronger and longer than normal.

According to the National Weather Service, gusts of up to 60 to 70 miles per hour were experienced on Thursday. Usually Santa Anas gust between 40 to 50 miles per hour. Santa Ana events generally last two to three days — the current event has lasted for more than five. This time, they're also especially dry, with humidity levels around one to two per cent in some places of the region. The stronger and longer lasting winds are a result of a particularly strong, particularly cold high-pressure ridge, sitting east of the Rockies. As the wind travels through that area of high pressure across the Great Basin towards areas of low pressure along California's coast, the wind speeds up, compresses and slams into Southern California.

Lack of rain is another factor. Between 2012 and 2016, California was riddled with extreme drought. Droughts in and of themselves aren't uncommon, but the most recent one was made worse by human-caused climate change, according to a paper written by A. Park Williams, a climate scientist at Columbia University. (There has been no rain in Los Angeles at all so far in this “wet” season.) 

The current lack of rain can be blamed on a ridge of high pressure sitting off the west coast of North America, blocking storms from passing over the State. 

USDA agriculture meteorologist Brad Rippey said:

“Hopefully this’ll [SIC] be a temporary feature, maybe it’ll stick around for just a couple of weeks, but man, I sure hope it’s not going to stick around for the entire winter."

Abundant research supports the theory that warming in the western tropical Pacific is associated with the arrival of blocking ridges This area seems to be warming faster than the other parts of the ocean. 

The melting of Arctic sea-ice could also contribute to the formation of ridges off the West Coast according to another recent study. Caused by global warming, the Arctic could be ice-free during the summer months resulting in large shifts in climatic patterns.

The other important factor in the fires is the fuel load. There was enough rain last winter to promote grass growth and there was also an abundance of dead brush, which had died during the drought. The grass has become tinder dry since then, not only from a lack of rain but also because of the heat during the record-setting summer and fall. 

As temperatures rise, so does the speed at which moisture evaporates from the soil. Higher temperatures combined with a lack of rain and dry hills covered in brush create perfect conditions for rapidly spreading fires.

According to Daniel Swain:

... this confluence of factors, of the really strong wind event this week, of these really hot, record hot conditions in the autumn and parts of the summer months as well, and then this lack of rain this fall ... Those three things right now would’ve contributed to the fires in Southern California being as bad as they are.

Trump, Abbott and all the rest of the deniers can bleat all they want, but Mother Nature always bats last. 

Dr Norm Sanders was a professor of geography at the University of California, Santa Barbara. He is also a former Tasmanian MP and Australian Federal Senator and a qualified commercial pilot and flight Instructor.

Creative Commons Licence
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Australia License

Monthly Donation

$

Single Donation

$

Get the facts. Subscribe to IA today.

 

Share this article:   

Join the conversation Comments Policy

comments powered by Disqus


Irenas Bookkeeping Services, Your XERO + MYOB Cloud Accounting Specialist