Posted on Categories Climate Change & Energy, Sustainable LivingTags , , , ,

Fire cause mystery: Winds not 'hurricane strength' as PG&E said

Paul Rogers, Lisa M. Krieger and Matthias Gaffni, BAY AREA NEWS GROUP

Investigators are looking at power line failures as a possible cause of the historic fires.

The heavy winds that downed power lines Sunday night at the start of the deadly wildfires raging across Northern California were far from “hurricane strength,” as PG&E has claimed, according to a review of weather station readings.
On Tuesday, the Bay Area News Group reported that Sonoma County emergency dispatchers sent fire crews to at least 10 reports of downed power lines and exploding transformers as the North Bay fires were starting around 9:22 p.m.
In response, PG&E said that “hurricane strength winds in excess of 75 mph in some cases” had damaged their equipment, but they said it was too early to speculate about what started the fires.
However, wind speeds were only about half that level, as the lines started to come down, the weather station records show. At a weather station in north Santa Rosa where the Tubbs fire started, the peak wind gusts at 9:29 p.m. hit 30 mph. An hour later, they were 41 mph.
Similarly, at another weather station east of the city of Napa, on Atlas Peak, where the Atlas fire started, wind gusts at 9:29 p.m. peaked at 32 mph. An hour later they were 30 mph.
Both speeds were substantially under the speed that power lines must be able to withstand winds under state law: at least 56 mph.
Read more at: Fire cause mystery: Winds not ‘hurricane strength’ as PG&E said

Posted on Categories Climate Change & EnergyTags , , , ,

Scientists see climate change in California's wildfires

Debra Kahn  & Anne C. Mulkern, SCIENTIFIC AMERICAN
As wildfires engulf nearly 170,000 acres of Northern California wine country, questions are swirling about the role of climate change in causing damage of historic proportions.
The fires, which started late Sunday night in the hills of Napa and Sonoma counties, quickly ballooned to 22 separate conflagrations in eight counties, killing at least 21 people by Tuesday evening. The Tubbs Fire, in Sonoma County, has been responsible for at least 11 deaths so far, making it the sixth-deadliest fire in state history. Nearly 300 people are still reported missing and 25,000 have been evacuated in Sonoma County alone, with more than 3,500 homes and businesses destroyed.
Strong winds were responsible for the fires’ quick incursion into urban areas, but months of record-high temperatures, preceded by heavy rainfall last winter, also fueled the destructive power of the fire that burned through the region, climate experts said.
Read more at: Scientists See Climate Change in California’s Wildfires – Scientific American

Posted on Categories ForestsTags , , , ,

California plans to log its drought-killed trees: may not reduce fire risk 

 Jane Braxton Little, HIGH COUNTRY NEWS

…at the heart of the logging debate is the question of whether dead trees are a fire hazard.  The conventional assumption is that insect outbreaks increase wildfire risk because dead trees are more flammable than green ones. That is a conclusion most scientists have long disputed.

Looking north from Blue Canyon near Shaver Lake, copper-colored forests blanket mountain slopes that stretch ridge after ridge to the horizon. The patches of fading green that dappled these hillsides last fall have merged into an unbroken cover of rust-needled pines.  At dusk, when the winds die down, an eerie stillness gives way to the muffled sound of munching as beetles chomp through one tree after another, thousands after thousands.

This is the look — and the sound — of drought.

Four consecutive winters with little to no snowpack, followed by four dry summers, have devastated California’s southern Sierra Nevada. At least 66 million trees are already dead statewide, and millions more are expected to die as the drought persists into a fifth summer.

On the Sierra National Forest, up to 90 percent of the mid-elevation ponderosa pines are dead.  Weakened by drought, oaks are succumbing to sudden oak death along the central and northern coast, and the disease has moved into the Central Valley. Pines gray as ghosts haunt coastal, Cascade and Sierra foothills. The epidemic is spreading across choice vistas owned by millionaires as well as remote landscapes rarely entered by humans.

And the bark beetles that caused this desolation? They’re reproducing at triple the normal rate. Forest ecologists used to consider them a natural part of the forest dynamic — and they are. Stressed by drought and decades of air pollution in overcrowded stands, however, the natural chemicals trees pitch out in self-defense can’t keep up with the onslaught of bugs.  No one is calling what’s happening here natural anymore.

“Nobody imagined this would come on as fast as it has, or be as lethal,” says Craig Thomas, conservation director for Sierra Forest Legacy, a coalition focused on Sierra Nevada national forest issues. “And nobody really knows what the hell to do.”

Overwhelmed by the die-off, forest management agencies are resorting to a century-old strategy: removing dead trees to minimize future wildfires, which they predict will be inevitable and cataclysmic. Gov. Jerry Brown declared a state of emergency in October, citing a public safety hazard from falling trees and worsening wildfire risks. The tree mortality task force he convened has marshaled a small army to log over 6 million acres.

Read more at: California plans to log its drought-killed trees (Forest fatalities) — High Country News

Posted on Categories Climate Change & Energy, WaterTags , , ,

Meet the insect that helped fuel the Valley fire destruction

Soumya Karlamanla, LOS ANGELES TIMES
Call it a vicious cycle: drought, wildfires and bark beetles.
California’s historic drought stresses trees across the state, making them ideal prey for bark beetles. The insect infestations dry out vegetation further, creating forests that can light up like tinder. Fires then damage more trees, attracting more beetles, and turning more forests brown.
“So we all have to hope for rain,” said Tom Smith, park pest management specialist for the Central and Southern Sierra Region for the California Department of Forestry and Fire Protection.

Bark beetles probably exacerbated the fire that ravaged Lake County over the weekend, he said. Experts called the Valley fire’s rapid spread unprecedented; the blaze, which began Saturday afternoon, grew to more than 40,000 acres in fewer than 12 hours.
“This last couple years has just been so extreme that everything’s under stress,” Smith said. “If we weren’t in the drought, we wouldn’t have so much bark beetle.”
He said there’s been heavy beetle activity in Lake County, and around Clear Lake, where the Valley fire is blazing. A U.S. Forest Service survey of the region in and around the Bay Area in June found that though tree mortality was increasing almost everywhere, the worst region by far was an area south of the lake.
UC Berkeley fire science professor Scott L. Stephens agreed that bark beetles in the area likely left dead trees ready to go up in flames. “There’s no doubt that’s going to enhance a fire,” he said.
He said that dead pine trees are much easier to catch on fire when they still have their needles, and they don’t lose them until a year after beetles kill them. Though pines that have been dead for years aren’t quick to ignite, the recently killed ones are standing fuel, he said.
Read more at: Meet the insect that helped fuel Northern California’s Valley fire destruction – LA Times

Posted on Categories ForestsTags , , Leave a comment on Op-Ed: More logging won’t stop wildfires

Op-Ed: More logging won’t stop wildfires

Chad T. Hanson and Dominick A. Dellasala, THE NEW YORK TIMES
In the fall of 2013, shortly after fire swept across 257,000 acres of forest and shrub lands near Yosemite National Park in California’s Sierra Nevada, Republicans in the House of Representatives approved a bill that would have suspended environmental laws to increase logging in our national forests in the name of fire prevention and “restoration.”
Fortunately, the legislation never made it out of Congress. But it is fire season again in the West and, predictably, House Republicans have struck again, passing a similar measure, almost entirely along party lines, that all but gives away public forests to logging companies. A similar bill promoted by three Western Republicans is now before the Senate.
Just as they did in 2013, supporters of this legislation are using the public’s fear of forest fires to advance their agenda. They argue that overgrown and “unhealthy” forests raise the risk of wildfires, and that the government has been hampered by litigation and environmental reviews from allowing timber companies to thin forests to reduce the risk of fire.
Accordingly, this legislation would allow more logging on federal lands, including clear cutting, by exempting some logging from environmental reviews entirely, limiting oversight in other cases and making it much more difficult to challenge harmful logging projects in court.
The legislation is rooted in falsehoods and misconceptions.Some of the bill’s supporters claim that environmental laws regulating commercial logging have led to more intense fires. But, as we saw in the 2013 fire near Yosemite, known as the Rim Fire and one of the largest in California history, commercial logging and the clear-cutting of forests do not reduce fire intensity.
Read more at: More Logging Won’t Stop Wildfires – The New York Times

Posted on Categories Forests, WaterTags , , Leave a comment on Ravaged by drought and bugs, North Coast forests prone to go up in flames

Ravaged by drought and bugs, North Coast forests prone to go up in flames

Glenda Anderson, THE PRESS DEMOCRAT
Thousands of trees in North Coast forests are dying, apparent victims of more than three years of drought and the bark-boring pests that flourish when water is scarce.
The dead and dying trees, mostly pines, are adding flammable fuel to forests where the fire risk is already high because of California’s prolonged drought. The dead wood won’t cause more fires, but once ignited, flames will burn hotter and be much more difficult to control, posing potential danger for rural residents and firefighters, fire officials say.
“It increases the intensity of the fire,” said Jim Wright, a Cal Fire division chief in Lake County, where most of the area’s dead trees have been found. “It’s just like starting a fire in your fireplace. It’s much easier to get a fire started when you have dry wood than green wood.”
The tree deaths are part of a larger, statewide problem that has ravaged the southern Sierra, where more than 10 million pine trees in national forests have perished. More than 12 million trees have died in national forests statewide in the past year because of drought and pests, according to U.S. Forest Service aerial surveys. Similar problems decimated pine forests in Colorado several years ago.
“Statewide, it’s horrific,” said Greg Giusti, forest adviser with the UC Davis Cooperative Extension. Statistics for state and privately owned forests were not available, but Giusti estimates the tree deaths in Sonoma, Mendocino and Lake counties to be in the tens of thousands.
Read more at: Ravaged by drought and bugs, North Coast forests | The Press Democrat