San Diego Get this: Johnny Cloud is into fog. Joel Blanket is into fog. Jerry Estberg (read "East Mountain") is into fog. Fog Cloud, Fog Blanket, Fog Mountain... Is this destiny or what?
The three scientists are united by one thought: All that fog we've been seeing waft across San Diego Bay this winter, disrupting air traffic at Lindbergh, causing crashes on the freeways, isn't a nuisance, it's a resource. We should be drinking it.
Fog, they say, is like a free desalination plant. It lifts water out of the ocean, extracts the salt, then brings all that freshwater vapor to us at head level, just begging to be drunk. A reliable water supply! Untapped!
But how to extract it? The answer is so simple, so low-tech it's almost silly. Fog blankets. Usually 100 square feet, made of porous plastic mesh, strung between poles, facing the oncoming fog. A drip tray below. Storage tanks capable of collecting, typically, 27 gallons of the purest drinking water every day. And that's just from one blanket, collecting fog droplets so small that it takes 10 billion of them to form one droplet of water.
"The reason I got onto this whole thing," says Jerry Estberg, a professor of physics at USD, "is I noticed as you drove up to Alpine [at a certain altitude] there was an increase in the size of the chaparral. I began to wonder why that was. Turned out it has to do with cloud layer. Above Alpine, above the cloud layer, it's quite dry."
A few visits later, Estberg realized that what was helping that level of chaparral -- everywhere in San Diego's foothills, from Iron Mountain to Mount Soledad -- was nothing less than low fog coming in, bumping against the hills and releasing its liquid.
"It turns out you get the maximum deposition right at what's called the 'inversion layer,' " he says. "The temperature, rather than dropping, goes up at a certain level, typically at 1500 feet. So I would go up above Poway -- there's kind of a shelf up there -- on the way to Ramona. It's just below Iron Mountain. There were several places: I also took data on Mount Soledad. This is a very cheap thing to implement. You basically put a screen up and set a trough below it to catch the water that drips off the screen. That's how I got started with the whole thing."
Entire ecosystems, like the Torrey Pine forest in Del Mar, he realized, depended for their survival on water they extracted from fog.
Graduate student John Cloud had the same epiphany.
"I am brand new getting into fog," he says, speaking from Santa Barbara, where he's experimenting with finding moisture to save native flora. "I'd had a wild idea: if I could capture summer moisture, it would help with the survival of my willows."
He got turned on to fog the first day he threw a fog blanket over a barbed-wire fence.
"There was a seemingly dry fog; there wasn't any precipitation or any wetness to the ground. But when I went back up to the barbed-wire fence, the mesh was soaked. It works very well in pulling the water out of the air. I'm doing it for ecological purposes, but I realized it has big possibilities for people, particularly under circumstances where access to good water is limited."
That's exactly what struck Joel Hernandez Blanket, a master's graduate in hydraulics from the University of Baja California. Blanket, from Ensenada, has launched a campaign to milk the fog for people living at some of Baja's most desiccated settlements. He has already built his first ten collectors at Punta Baja (also known as Fish Camp), a poor community of 60 people on the coast near the town of El Rosario, 250 miles south of San Diego. There, the fog rolls in over the headland pretty much year-round.
"I began [construction] last September, and I'll finish this September. It will be 30 collectors of 100 square feet each, 3000 square feet. They'll extract 3000 liters of water per day from the fog -- say 800 gallons -- enough for 90 people. And Punta Baja only has 60 residents. That's over 30 liters or nearly 10 gallons each per day."
Blanket says the fog blankets will supply all water needs for "at least half of the year."
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Blanket, Cloud, and Estberg owe much of what they have learned to the guru of the fog movement, Robert Schemenauer, a 51-year-old "cloud scientist" from Toronto. Estberg says Schemenauer is known as the "international gadfly of fog water collection."
It was Schemenauer who noticed how many hot, dry coastal lands coexisted with cold-water currents and had little or no rainfall yet lots of fog. Schemenauer has traveled the world seeking out sites, from Yemen to Ecuador to South Africa to the mountains of Nepal. Above all, the dry sands of Chile's Atacama coastal desert communities gave him an opportunity to try out his theories. One name has made him famous: Chungungo, a dying Chilean Atacama village of 330 he saved with 88 fog blankets.
"We started working there in 1987," he says. "The population was going down. There wasn't too much hope for a better future. People [were] moving away to live in [the slums of] big cities, hoping for work.
"We erected 88 large fog collectors. They worked! They produced an average of about 3000 gallons a day. On very good days they'll produce 25,000 gallons or more. The water is supplied year-round, though there's a seasonality to it. Their [Southern Hemisphere] springtime months, October, November, December, are the best. In summer and winter the elevation of the cloud changes. We [have set up the fog collector blankets] at a range of altitudes that is chosen to allow us to collect a lot of water at the best times of the year and moderate amounts of water at the poorer times."
Schemenauer says the effect on the community has been dramatic.