Note: Lana Cohen is a Report For America fellow covering the environment & natural resources for TMV & KZYX. Her position is funded by the Community Foundation of Mendocino, Report for America, & our readers. You can support Lana’s work here or email [email protected]. Contact Cohen at LCohen@mendovoice.com. TMV maintains editorial control.
LITTLE RIVER, 1/29/2021 — San Luis Obispo County received over 15 inches of rain in some areas, Mammoth Valley was hit with almost 110 inches of snow, mudslides decimated parts of Salinas, and destroyed Highway 1 in Big Sur. In Mendocino County, areas of Brooktrails, Laytonville, and Willits are still without power and U.S. Route 101 was closed at several points. Winter weather has officially arrived in the state and even by California standards, the storm was unusually destructive and wet.
As we all know, it’s not unusual for the rainy season to start out relatively, well, un-rainy, and then for the state to get hit with a big storm — though not quite like this one. “This storm definitely has more water in it because of climate change,” explained Michael Wehner, a senior scientist who studies extreme weather events and their relationship to climate change at the Lawrence Berkeley National Lab. According to research from Wehner, climate change is driving processes that make winter storms drop more precipitation than has historically been the case in NorCal.
When the atmosphere is warmer, it can hold more moisture. Due to our (about one degree Celsius) warmer planet, atmospheric rivers, which are essentially giant rivers in the sky that are made of water vapor and bring precipitation, are holding more moisture and delivering more intense storms.
“This storm has between six to seven percent more water in it,” said Wehner in an interview, who noted, on Wednesday morning, that heavy snow was falling outside his home in Tahoe. “This is well established, we know that this storm has more water in it because of the human changes to the composition of the atmosphere through the burning of fossil fuels — coal, oil, natural gas.”
To break that idea down, there’s a formula called the Clausius-Clapeyron equation. The equation defines the relationship between heat and the amount of water that the air can hold. It finds that for every one degree celsius rise in temperature, the air can hold six to seven percent more water, and therefore drop six to seven percent more precipitation on us. “We have very clear proof and evidence that the global climate is about one degree warmer [celsius] than it was before the industrial revolution,” said Wehner. “We have high confidence that human activities have increased atmospheric moisture and every storm has more water because of it.”
Thus Wehner concludes that because the climate is one degree celsius warmer than it was back in the 1800s, this recent storm dropped six to seven percent more precipitation. So because the temperature of the planet continues to skyrocket, even more intense storms should be expected for the future. “It’s clear that the number of intense storms, simply because of this moisture argument will increase,” said Wehner.
Although the storm may have brought more moisture to the ground, in many places across the state, this particular storm wasn’t actually that extreme, according to Marty Ralph, a research scientist who studies meteorology at the University of California Scripps Institute of Oceanography Center for Western Weather and Water Extremes.
Ralph has been studying atmospheric rivers for 20 years. He actually created a scale to rank atmospheric rivers in terms of severity, using a scale that is similar to the way hurricanes are categorized.
In this storm, the atmospheric river that hit North of San Francisco only received an atmospheric river ranking 1 (AR1) on Ralph’s scale, which runs from AR1 to AR5 with AR1 being a mostly beneficial, non hazardous storm with relatively light rain that moves over an area quickly — and AR5 being a largely damaging storm that brings heavy rain and stalls for a long period of time.
Other areas of the state did receive higher AR rankings. The atmospheric river over the central coast, which stalled for an extended period of time bringing heavy rain, mudslides, and serious damage, was ranked AR3. Storms of that caliber are only expected to hit that region once a year or once every other year, according to Ralph.
The atmospheric river scale is pretty new to the scene. Ralph created the scale with the intent of helping people better understand the relationship of atmospheric rivers to precipitation, hazards, and water supply. “For communication and situational awareness we needed to distinguish between run of the mill ARs that are weak but mostly beneficial [by bringing water supply] and the big nasty ones that are mostly hazardous,” he said in an interview.
Atmospheric rivers can be extraordinarily powerful. “Atmospheric rivers are rivers of water vapor in the sky that are pushed along by the wind rather than a river of liquid like we have on the landscape,” explained Ralph. “But they can transport even more water vapor than the biggest rivers transport on earth as liquid.”
Ralph said that an average atmospheric river can move 25 times Mississippi Rivers discharge into the Delta at the Gulf of Mexico or twice the discharge of the Amazon into the Atlantic Ocean. “They’re literally the biggest rivers on earth, it’s just that they’re vapor in the air instead of liquid on land.”
The scale that Ralph created to define atmospheric rivers is based on two parameters — strength, or how hard it’s raining, and duration, or how long it stalls over a specific location. So an AR1 would bring some light wind, light rain, and maybe a build up to some heavy rain or even very heavy rain for a brief period of time. A stronger atmospheric river, the type that would be hazardous and cause mudslides and debris flow would bring heavy or very heavy rain over an extended period of time, possibly dropping as much as half an inch of rain in 15 minutes. Atmospheric rivers are also correlated to the financial burden they might bring, with AR3’s usually costing 10s of millions of dollars and AR5s 100’s of millions.
The negative impacts of these bigger storms are exacerbated by more intense, mega-fires, explained Michael Wehner. “There’s a lot going on at once,” he said. “To the extent that fire frequency increases and big storms increase, one could expect more landslides and mudslides.”
As we were having this conversation, on Wednesday, a mudslide from the River Fire was pouring into Salinas.
“Wall of mud, water, debris flowed down from #RiverFire burn scar and into homes on River Road in Monterey County. Two people hurt. 50 horses were rescued,” tweeted NBC Bay Area reporter Ian Cull.
The week’s storm has now mostly petered out and most of Mendocino will experience a day of reprieve today. According to Scott Carroll, senior forecaster at the National Weather Service Eureka, more rain is on its way to Mendocino County. Carroll said that the next atmospheric river to move over the state looks very weak. Marty Ralph ranked it an AR1, so the rain should bring enough precipitation to start filling up reservoirs and rivers, but not enough to cause any serious damage.
The 125 year climate alarm farce : (Google all of this to verify)
In 1896, after a series of heat waves Swedish scientist Svante Arrhenius claims that burning coal will soon cause global warming. (1896 Heat Wave) (1870 Seattle Heat Wave).
WATER VAPOR, not co2 gas is the greenhouse gas which has a significant contribution to atmospheric warming.
The 1930’s DUST BOWL era was once considered the hottest decade ever recorded until NASA and NOAA REVISED the temperatures. Google NOAA TEMPERATURE ALGORITHYM. NASA TEMPERATURE ALGORITHYM.
Burn acreage in the western US has dramatically dropped since the 1930’s.
In the 1970s there was widespread fear of an impending ice age. In 1978 scientists began warning of global warming again. There have been dozens of failed predictions for climate catastrophe since then.
Since the 1800s there have been endless reports of major Artic Ice loss, crazy weather phenomenon and failed preditions.
Okay, reading the two replies above I feel compelled to say the comments need to be moderated, disclaimers added when appropriate. And nobody but moderators should have to read something as foul as the first comment above. I value this project in local journalism for its power to build community and we won’t get there without mutual respect.
And Lana Cohen, thank you for a well-written, carefully and thoroughly-sourced story. Great reporting! Really enjoyed your recent Coho salmon piece, as well. Both stories a pleasure to read!
Well said. It’s sickening that some feel the need to blame & preach about Climate change being a leftest thing. True we are are going to get more severe storms because we haven’t had any real storms in years. It’s common sense. But at the same time Climate Change is a real thing, believe it or not.
Censoring profanity is fine, but censoring opinion you disagree with is not. This country is becoming zero tolerant on the political left.
I’ll replay your praise to Lana.
TRILLIONS OF DOLLARS are going to be spent on the climate alarm farce. We will be broke as a joke. This money could be spent on purchasing public lands for us and nature to enjoy, restoring native fisheries, cleaning up toxic sites and housing homeless people who are too troubled to hold their own.
California is at the mercy of the jet stream to bring rain, snow and cool air. Paleoclimatology scientists have strong evidence using tree ring data and river sediment data indicating that droughts have lasted many decades in California.
As a kid in the 1970s I lived through a severe California drought cycle and there was talk of towing an iceberg to SoCal.
As a teenager in the 1980s I lived through a severe wet El Nino cycle. Google Love Creek mudslide Ben Lomond, CA.
As a twentysomething I lived through another California drought cycle in the late 80s/early 90’s.
As a thirtysomething I lived through a super wet period in the late 90’s.
In 2009 I was working in Humboldt with hail, sleet, below average temps, and above average precipitation. I KNEW from experience that a warm drought cycle was on the way.
The hottest temp recorded was 134 F on July 10, 1913 in Death Valley, CA.
QUESTION AUTHORITY AND DO NOT CENSOR OPINION.
Get used to it. From now on, when there is a major weather event there will always be a link to Climate Change to blame for it. It is our fabled “Big Bad Wolf.” The Climate Change plan of action requires a carbon tax solution where everyone should have to pay. If you do not agree to it then you are just a “big dummy”. So just, shut-up and pay your fair share of taxes so we can all be safe from apocalyptic wildfires, floods, droughts, cyclones and hurricanes. Human activities, not nature, are the root cause of all the harm coming to humankind. Maybe that’s why there’s no mention of having a standby generator, clearing brush from around your house, having an emergency food supply and an evacuation plan. It takes away from the taxing argument.
Even if you completely shut down fossil fuel burning in the United States you would still have over 80 percent of the emissions on the planet continuing to pollute. That’s how ludicrous this idea is. Are you going to censor this fact too, editor ?
Even if you completely shut down fossil fuel burning in the United States you would still have over 80 percent of the emissions on the planet continuing to pollute. That’s how ludicrous this idea is. Are you going to censor this fact too, editor ?
Here we go again. I always have the same reaction when I read “Climate Change” in what is supposed to be a “news” report; I just think “politics again.” Also when I hear the Governor say all the wild fires are due to “Climate Change” I think about him avoiding responsibility. If you can blame the fires on everyone who drives a car then no one will be talking about forest management, dead trees, clearing of brush and burn piles. Everyone is to blame so no one is to blame. “Climate Change” should be laughed at, like World Peace is achievable and ending Global Hunger.
Footnote: I you want to make a global change don’t bother me and my truck MPG, go and convince China and India to do something about their carbon emissions. Just leave me alone. Thank you.
Footnote: If you want to make a global change don’t bother me and my truck MPG, go and convince China and India to do something about their carbon emissions. Just leave me alone. Thank you.