One more thing to worry about – fog shortage

UPDATE: Roger Pielke Jr. alerts us to this:

Last summer the San Francisco Chronicle carried a story about research on fog and climate with a different conclusion:

The Bay Area just had its foggiest May in 50 years. And thanks to global warming, it’s about to get even foggier.

That’s the conclusion of several state researchers, whose soon-to-be-published study predicts that even with average temperatures on the rise, the mercury won’t be soaring everywhere.

“There’ll be winners and losers,” says Robert Bornstein, a meteorology professor at San Jose State University. “Global warming is warming the interior part of California, but it leads to a reverse reaction of more fog along the coast.”

The study, which will appear in the journal Climate, is the latest to argue that colder summers are indeed in store for parts of the Bay Area.

More fog is consistent with predictions of climate change. Less fog is consistent with predictions of climate change. I wonder if the same amount of fog is also “consistent with” such predictions? I bet so.

From the University of California – Berkeley via Eurekalert:

Fog has declined in past century along California’s redwood coast

Analysis of hourly airport cloud cover reports leads to surprising finding

California’s coastal fog has decreased significantly over the past 100 years, potentially endangering coast redwood trees dependent on cool, humid summers, according to a new study by University of California, Berkeley, scientists.

It is unclear whether this is part of a natural cycle of the result of human activity, but the change could affect not only the redwoods, but the entire redwood ecosystem, the scientists say.

“Since 1901, the average number of hours of fog along the coast in summer has dropped from 56 percent to 42 percent, which is a loss of about three hours per day,” said study leader James A. Johnstone, who recently received his Ph.D. from UC Berkeley’s Department of Geography before becoming a postdoctoral scholar in the campus’s Department of Environmental Science, Policy and Management (ESPM). “A cool coast and warm interior is one of the defining characteristics of California’s coastal climate, but the temperature difference between the coast and interior has declined substantially in the last century, in step with the decline in summer fog.”

The loss of fog and increased temperature mean that “coast redwood and other ecosystems along the U.S. West Coast may be increasingly drought-stressed, with a summer climate of reduced fog frequency and greater evaporative demand,” said coauthor Todd E. Dawson, UC Berkeley professor of integrative biology and of ESPM. “Fog prevents water loss from redwoods in summer, and is really important for both the tree and the forest. If the fog is gone, we might not have the redwood forests we do now.”

Fog in the redwoods

The scientists’ report will be posted online during the week of Feb. 15 in advance of publication in the journal Proceedings of the National Academy of Sciences.

The surprising result came from analysis of new records recently made available by the National Climate Data Center. The U.S. Surface Airways data come from airports around the country, which have recorded for more than 60 years hourly information such as cloud cover (cloud ceiling height), visibility, wind and temperature.

Johnstone evaluated the data from airports along the northern California coast and found two airports – Arcata and Monterey – that had consistent fog records going back to 1951. With these data, he was able to show that frequent coastal fog is almost always associated with a large temperature difference between the coast and inland areas.

Using a network of 114 temperature stations along the Pacific Coast, Johnstone and Dawson demonstrated that the coast-inland contrast has decreased substantially, not just in Northern California, but along the entire U.S. coastline from Seattle to San Diego. This change is particularly noticeable in the difference between Ukiah, a warm Coast Range site in Northern California, and Berkeley on San Francisco Bay. At the beginning of the 20th century, the daytime temperature difference between the two sites was 17 degrees Fahrenheit; today, it is just 11 degrees Fahrenheit.

The relationship between temperature gradient and fog frequency implies a 33 percent drop in fog along the coast during this time.

Greater fog frequency is connected to cooler than normal ocean waters from Alaska to Mexico and warm water from the central North Pacific to Japan. This temperature flip-flop is a well-known phenomenon called Pacific Decadal Oscillation – an El Niño-like pattern of the north Pacific that affects salmon populations along the US West Coast. The new results show that this pattern may also have substantial effects on the coastal forest landscape.

In addition, the data show that the coast gets foggier when winds blow from the north along the coast, which fits with observations that northerly winds push surface waters offshore and allow the upwelling of deep, cold, nutrient-rich water.

“This is the first data actually illustrating that upwelling along the Pacific coast and fog over the land are linked,” Johnstone said.

By pulling in data on temperature variation with elevation, Johnstone and Dawson also related their fog data with a temperature inversion that each summer traps the fog between the coast and the coastal mountains. The inversion is caused by a warm, dry, high-pressure cell that sits over Northern California in late summer, bringing hot temperatures to inland areas, including the Central Valley. If the inversion is strong, its lower boundary at about 1,200 feet keeps a lid on the cool marine layer and prevents fog from penetrating over the Coast Ranges. When it is weak, the ocean air and clouds move upward and inland, resulting in a cooler interior and a warmer, drier coast.

“The data support the idea that Northern California coastal fog has decreased in connection with a decline in the coast-inland temperature gradient and weakening of the summer temperature inversion,” Johnstone said.

“As fog decreases, the mature redwoods along the coast are not likely to die outright, but there may be less recruitment of new trees; they will look elsewhere for water, high humidity and cooler temperatures,” Dawson said. “What does that mean for the current redwood range and that of the plants and animals with them?”

Eventually, Dawson and Johnstone hope to correlate fog frequency with redwood tree ring data in order to estimate climate trends going back hundreds of years.

“While people have used tree ring data from White Mountain bristlecone pines and stumps in Mono Lake to infer climate change in California, redwoods have always been thought problematic,” Dawson said, mainly because it’s hard to determine whether the width of a tree ring reflects winter rain, summer fog, temperature, nutrient supply or other factors. “Stable isotope analyses of wood cellulose allows you to pull this data out of the tree ring.”

Dawson has established that the isotopes of oxygen in a tree reflect whether the water comes in via the leaves from fog, or via the roots from rainwater. “Redwoods live for more than 2,000 years, so they could be a very important indicator of climate patterns and change along the coast,” he said.

The new fog data will allow Dawson and Johnstone to calibrate their tree ring isotope data with actual coastal fog conditions in the past century, and then extrapolate back for 1,000 years or more to estimate climate conditions.

The work was supported by the Save the Redwoods League and the Berkeley Atmospheric Sciences Center.

================================================

Further reading: Fog in California from UCSB

http://www.geog.ucsb.edu/~joel/g110_w08/lecture_notes/california_fog/cal_coastal_fog1_sm.jpg
Advertisements

  Subscribe  
newest oldest most voted
Notify of
wws

Yes, comparing current satellite photos with those taken a hundred years ago confirms just how dramatic the loss in fog coverage is.

I reckon all that missing fog has just migrated on up to Sacramento and infused the minds of the state legislators.

kim

Advocacy science. Bah.
==============

Patrik

Hmmm… Is fog cooling or warming?

crosspatch

We have had recently been in a 30 year “warm” cycle of the PDO that results in, as I understand it, less rainfall in our area. We have had several dry periods over the past 20 years (remember the 6-year drought that ended in the early 1990’s?). Wind patterns that often have Easterlies flowing offshore would prevent the fog coming inland.
I have noticed this winter in the Bay Area that we have had more cloudy days than I can remember in recent years but I have no hard data to support that. It is simply something I have noticed in my daily travels outdoors.
As I type this at about noon in San Jose, the morning “marine layer” has not yet completely burned off and we still have high thin clouds.
It would not seem unreasonable to expect the amount of fog to vary with long term climate cycles. What I might be curious to see is how the PDO cycle looks compared to amounts of fog seen along the Pacific coast. I am skeptical, however, of tree rings being used as a proxy for humidity. They should make up their minds … are trees thermometers or are they hygrometers?

Gary Hladik

Hmm. If there are redwoods more than 2,000 years old, then that suggests that at least some of the trees are quite resistant to natural variations in climate, including the RWP, MWP, LIA, and probably MMGW (Mann-made Gorebal warming).

Michael Jankowski

Under a warming scenario, shouldn’t inland areas warm-up more than the moist coastal areas and increase the gradient, producing more fog?
Should it be any surprise that, “This change is particularly noticeable in the difference between Ukiah, a warm Coast Range site in Northern California, and Berkeley on San Francisco Bay,” considering the UHI of Frisco?

Andrew30

When has this happened before?
How old are these trees?
Is there a problem?

Billyquiz

Richard North at EuReferendum has already debunked this story:
Hot on the trail of the Golden-Gate scam, a readers draws my attention to an article in the San Francisco Chronicle for 6 July 2009.
The title of the piece somewhat gives the game away, as it declares: “Get ready for even foggier summers”. The opening lines of the text tell us that the Bay Area just had its foggiest May in 50 years. “And thanks to global warming, it’s about to get even foggier.”
This makes an interesting counterpoint to the article in The Daily Telegraph today, proclaiming: “Fog over San Francisco thins by a third due to climate change”.
http://eureferendum.blogspot.com/2010/02/you-will-love-this.html
PS. Sorry if this appears twice, I submitted it a few minutes ago but it doesn’t seem to have registered!

Steve Goddard

Every time I have been to the beach in Monterey or Carmel, fog shortage has not been a problem. Staying warm in the fog is a problem.

Sean Peake

Aside from all the fog having gone to Vancouver, I’d be interested in the wind records from those stations.

From EU Referendum today:
“Hot on the trail of the Golden-Gate scam, a readers draws my attention to an article in the San Francisco Chronicle for 6 July 2009.
The title of the piece somewhat gives the game away, as it declares: “Get ready for even foggier summers”. The opening lines of the text tell us that the Bay Area just had its foggiest May in 50 years. “And thanks to global warming, it’s about to get even foggier.””

Good grief! Polar bears dying, snow disappearing, the sky is not foggy. What else can these doom and gloomers come up with. Berkely immediately raised my suspicion. Good story for more study and grant money I suspect. Kali-fornia is bust. The USA is bust. Who is going to pay for this? Not me I hope.To heck with it, I’m going hillwalking.

View from the Solent
Royaul43

The 3rd to last paragraph is the key as to why tree rings are not a good proxy for temperature. Most ring width differences are due to water availability of that year, though other factors may have an effect.

JohnH

So higher temps mean less fog, less fog means lower tree growth, less growth means smaller ring thickness. So going back and using ring thickness as a proxy for temp does not work in this area, no doubt there are other variations to this theme eg frosts,cloud cover, weed growth, moss cover etc etc all over the world which also give the same odd results.
Does that mean we can have a Global Medieval Warm Period back ?

Squidly

What did they say?
All I heard was … blah blah blah … cause by man’s activity … blah blah blah
Yeah .. whatever…

Squidly

Well, I suggest they cut them all down now before it’s too late!

Well I think that it all must have come up here. Normaly we get 2-4 days of fog per year. This winter we have had 20+ days. It is kind of crazy. I have never seen it like this.

mdjackson

This is a direct result of the Green Movement. The factories that used to pump out particulate matter that the fog stuck to aren’t doing it any more. The air is free of fine particulates and the fog has nothing to stick to. Same thing happened with London, England. You don’t see the pea-soup thick fog anymore because they cleaned the air.
So start up those factories and begin pumping C02 back into the air. Then the fog will stay and as an added bonus California’s economy will improve.
Or maybe not. I don’t know.

DirkH

The article is flawed: It fails to mention that these trees are huge carbon sinks. No funding for you.

Doug in Dunedin

Just noticed that Michael Mann is a Keynote speaker for one of the sponsor’s of this paper. Redwoods League and the Berkeley Atmospheric Sciences Center.
Not to put too fine a point on it but it looks as though this paper is intended to alarm the good people of San Francisco just a tad.
Redwoods League and the Berkeley Atmospheric Sciences Center.
You are invited to participate in the Eighth Atmospheric Science Symposium sponsored by the UC Berkeley Atmospheric Sciences Center (BASC). Please use the web form to register and submit your poster title.
This symposium will be a one day event including keynote seminars, poster sessions, and discussion.
Friday, February 26:
Slusser Auditorium
International House, UC Berkeley
9:00am Michael Mann (Penn State) Learning About Climate Dynamics Using Paleoclimate Information From Past Centuries

Robert

Heavens! It’s worse than we thought!

Ibrahim
Robert

” kim (12:10:49) :
Advocacy science. Bah.”
Seriously? You do realize that half the papers on this site are either out-and-out funded by the energy lobby, written by non-specialists sticking their oar into climate science specifically for the political purpose of trying to discredit AGW, or both? And you want to talk about “advocacy science”? Ballsy.
OK, I’ll bite. What is it about this study of ocean currents, fog, and redwood trees that makes it “advocacy science”?

Obviously, to save the redwoods, all of California will have to be evacuated.

MinB

The article states that the difference between inland and coastal summer temps have decreased, but it didn’t specify if that was cooling interior or warming coast or both. I also would suggest that other factors could be in play. I grew up in No. Cal, as did my father who would be in his eighties if still alive, and we both noticed a change over our lifetimes in the climate due to increased humidity from irrigation. I no longer live there, but my friends who do say they’re starting to get afternoon thunderstorm clouds that never existed just 15 years ago.

gcb

I thought that CO2 increase was supposed to drive an increase in water vapour, which was the real danger since water is a more effective “green house gas”. Shouldn’t that INCREASE the amount of fog?
Still confused…

p.g.sharrow "PG"

Among the factors they will need to investigate the effects of irrigation and farming changes in the central valley over the last 150 years. These have had a impact on the valleys’ heating due to evaporation and ground cover changes. 150 years ago the central valley was ether swamp or desert, often in the same year 😉

George E. Smith

Well since I drove to SF and back this morning, I can attest to the fact that the fog is alive and well in Northern California.
Funny thing is it was nice and goggy yesterday too, so that makes it more like climate than weather.
Who has the 1910 Satellite photos of all that megafog ?

Dave Andrews

OMG, the weather changes all the time which creates havoc with our scientific studies. I mean, I’m a 30 year old PhD student and I haven’t seen anything like it before. These trees which have been around for hundreds, even thousands, of years don’t know what’s going to hit them!

rbateman

What fog shortage? What are they talking about?
The work was supported by the Save the Redwoods League and the Berkeley Atmospheric Sciences Center.
Oh, I see.
Maybe in the Bay Area, there is a shortage of fog, but it ain’t so in the NorthState. As the Sun sank into i’ts Deep Solar Minimum the fog ran inland.
So far, it’s just gotten worse. The Fog used to form in the Winter after dark.
Now it forms in the afternoon in Winter and into late Spring after dark.
So, in other words, the Fog has found a new home.
Using a network of 114 temperature stations along the Pacific Coast, Johnstone and Dawson demonstrated that the coast-inland contrast has decreased substantially, not just in Northern California, but along the entire U.S. coastline from Seattle to San Diego. This change is particularly noticeable in the difference between Ukiah, a warm Coast Range site in Northern California, and Berkeley on San Francisco Bay.
Cherry pick, cherry pick.
The loss of fog and increased temperature mean that “coast redwood and other ecosystems along the U.S. West Coast may be increasingly drought-stressed, with a summer climate of reduced fog frequency and greater evaporative demand,” said coauthor Todd E. Dawson, UC Berkeley professor of integrative biology and of ESPM. “Fog prevents water loss from redwoods in summer, and is really important for both the tree and the forest. If the fog is gone, we might not have the redwood forests we do now.”
OMG, it’s got to be global warming. What else can it be?
It is unclear whether this is part of a natural cycle of the result of human activity, but the change could affect not only the redwoods, but the entire redwood ecosystem, the scientists say.
Try the Younger Dryas, where this place turned into a semiarid desert for 1,000 years.
Oh, bother.

intrepid_wanders

No problem at all. As long as the CO2 continues to increase, the trees water collection efficiency increases…
http://aob.oxfordjournals.org/cgi/content/abstract/104/1/179
More of the same garbage.

Mike Ford

Just follow the money. If advocacy organizations like this can’t come up with a science “cause of the day” you can be scared in, they won’t get much in donations.
If this is really true, I have an idea. We can float 1000’s of ships just offshore to spray water into the air, thus helping the creation of fog. And we can power the pumps using giant floating solar arrays that span the Pacific all the way to Hawaii. /sarc off

UK John

Is fog just caused by mechanisms they attest?
fog days in UK have almost disappeared from the begining of the 20th century to now, this is all due to human influence, we now have clean air! the same maritime climate but not the geography, so who knows
wouldn’t fog make the land cooler ? it used to make my childhood winter fog days very chilly. perhaps thats why the record now shows its a bit warmer in the UK winter (pet theory)
so they conclude the decrease in fog is maybe connected to climate change or maybe not, I could have concluded that! looks a bit of a waste of time, a good use of taxpayers money?

If they calibrate the way paleo does to a trend we will see another hockey stick.

Don Penim

Feb 16, 2009 / San Francisco Chronicle front page headline stating:
“Less fog puts redwoods at risk, scientists say –
A gradual decrease in summer fog along the California coast over the past century may be endangering the region’s giant redwoods and affecting the ecology of the area surrounding the trees, according to a study by UC Berkeley scientists”
http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/02/16/MN3G1C05BD.DTL&type=green
July 06, 2009 / SF Chronicle headline stating the opposite:
“Get ready for even foggier summers”
The Bay Area just had its foggiest May in 50 years.
And thanks to global warming, it’s about to get even foggier.
That’s the conclusion of several state researchers, whose soon-to-be-published study predicts that even with average temperatures on the rise, the mercury won’t be soaring everywhere.
“There’ll be winners and losers,” says Robert Bornstein, a meteorology professor at San Jose State University. “Global warming is warming the interior part of California, but it leads to a reverse reaction of more fog along the coast.”
http://articles.sfgate.com/2009-07-06/entertainment/17218478_1_warming-fog-vapor-cloud
The Bornstein’s study referenced may be this one that was published later that year:
“Observed 1970-2005 cooling of summer daytime temperatures in coastal California . Lawrence Berkeley National Laboratory”
http://www.escholarship.org/uc/item/7c05q7cv

Doug in Dunedin

My point is that the conversation goes like this:
Question “Does this mean that this loss of fog is due to CAGW?”
Answer “You might say this but I couldn’t possibly comment”
Doug

Don Penim

Should read : Feb 16, 2010/ San Francisco Chronicle
Thanks moderator

but but but I thought we just learned that warming INCREASED moisture in the air……….

b.poli
Al Gore's Holy Hologram

It’s all YOUR fault!

OT:
but worthy of a mention.
“Science blogger finds errors in Met Office climate change records”
http://www.timesonline.co.uk/tol/news/environment/article7028362.ece
This was doing the rounds on Bishop Hill but now seems to have found itself into the MSM
(Gate de l’Heur)

Lokki

“Save the Redwoods League, along with Berkeley Atmospheric Sciences, funded the study. ”
http://news.mongabay.com/2010/0215-hance_redwood.html
Doesn’t necessarily mean nuthin’

James Allison

One thing is certain we can blame Climate Change for decreasing fog levels

Ray

Maybe deforestation has to do with the difference of temperature and humidity on the coast and its role in the fog.

Philip Lloyd

I wonder whether it has anything to do with the salt content of the local aerosol? I have been studying the NADP data on the chemistry of rain, and have found a three-fold drop in the Na and Cl flux between 1984 and 2006, all the way along the west coast from California to Washington. At present the best hypothesis I have for the phenomenon is a rise in detergent-containing effluents affecting the generation of sea-salt droplets that carry the salt into the air in the first place.

PJB

It is best not to “slam” any and every presentation of data whether accompanied by speculation or not. This is how the debate is developed and new questions are formulated.
An open mind leads to more productive studies in the long run. It was just the closed-minded approach of the AGW proponents that caused a lot of the issues that are presently coming to light.
Mitigation or instigation? If we are causing something then it should be provable above the “noise” of the climate record and we can then devise potential approaches to further damage…er correct.. the situation.
As long as there is no statistically significant effect regarding our input into the system, how can we even contemplate any kind of action, one way or the other?

Scuff

Climategate has a post that references studies that aruge less/more fog is due to warming.
I’m very confused.
http://www.climategate.com/climate-change-causes-an-increase-and-a-decrease-in-san-francisco-fog

Andrew30

So it will be front page news today.
Will the 1,000 year extrapolation be front page news if it shows that this is normal?
I guess the “Save the Redwoods League” would rather release an incomplete report and an ominous news release now rather than wait for the anything that might put the report in context.
“..are not likely to die outright,”
How ‘not likely’?
Is it maybe 100% ‘not likely’, or just not significantly likely?
“It is unclear whether this is part of a natural cycle of the result of human activity”
Translation: We have no idea why this happens but the “Save the Redwoods League” insisted that we include a possible human connection.
“Using a network of 114 temperature stations along the Pacific Coast…”, Hmmm.
“While people have used tree ring data…”, Hmmm.
This all sounds familiar.
Where is the data?