Dan Brekke

Highway 120 in Yosemite National Park winds toward Tioga Pass. The road closed Tuesday night after its longest winter opening since at least 1933.

It first captivated me back when I was an adolescent map reader back in the Midwest. I was poring over maps of California for a trip that didn’t happen—then—and took note of the roads across the Sierra Nevada. And the highest of all the mountain routes I could see crossed Tioga Pass, at an altitude that rounds to 10,000 feet. Nearly two miles above sea level.

Eventually I took that trip to California, but it was still a long time before I actually saw the place the map depicted. A good 15 years or so after I moved out here, I managed to scramble up there on a long weekend and spent a single afternoon driving Highway 120, the Tioga Road.

The stark beauty of the Sierra always manages to surprise me, but there’s an extra degree of immediacy to the grandeur along the road to the pass. After rising through a stretch densely lined with conifers, you emerge into a world of granite domes and alpine meadows. It almost seems wrong to be driving through this landscape instead of walking through it (although there’s plenty of opportunity to do that on dozens of trails, if you give yourself time). Approaching from the west, the pass itself is a little anticlimactic. You note the country is getting a little drier, you pass the Tioga Pass entrance sign with the announcement of the spot’s elevation—9,943 feet above sea level—and then you begin a nonstop plummet toward the town of Lee Vining and Mono Lake.

The feeling I came away with, and that I’ve experienced every time I’ve been across the road, is a sense of having been allowed to see a stretch of road that’s a little bit of a secret – it’s much less traveled than most routes into and out of Yosemite – and, without having had to work very hard for it, have been given access to one of California’s greatest treasures.

All of which goes to explain that when high country fanatics began writing about how the road was open in December because of this season’s dry weather, I got the urge to go up there and see what the winter scene looked like. And at the first excuse, I headed up to the pass.

That feeling of being allowed to enter a special world was stronger than ever. I hadn’t planned on doing a radio piece about the trip, but I had brought my little sound kit, which fits into a fanny pack, just in case. When I climbed out of the car at Tenaya Lake, elevation 8,150 feet, I slowly realized that the weird moaning-whale song sound I was hearing was the lake’s thick ice expanding in the sunlight. I just had to record that. And then maybe talk to some people.

Virtually everyone I talked to on the lake and later, on a trail above Tioga Pass, shared the opinion that this was a once-in-a-lifetime opportunity, to be able to drive into the middle of the high country. They talked about the special quality of the winter light on the landscape, the opportunity to change their usual winter routines of snow shoveling and skiing, and the simple amazement they felt in being able to walk and skate and picnic nearly two miles above sea level—in the middle of January.

Dan Brekke

Gaylor Lakes Trail, elevation 10,500 feet, just above Tioga Pass in Yosemite National Park. In the center background, Dana Meadows. This area is typically snowed in by Thanksgiving and the Tioga Road through the area is normally closed until late spring or early summer.

But people also talked about the disturbing part of what they were seeing. Long-time Californians seem to develop an ingrained understanding of the state’s hydrological equations and how important the Sierra Nevada winter snowpack is to maintaining a healthy environment, not to mention delivering water to farms and cities. And looking around, people expressed some worry about the beautiful but mostly snow-free country around them. (A data point here: The daily snow survey summary from the state Department of Water Resources show that the statewide average for snow-water equivalent in the mountains is just 10% of normal. It will be most interesting to see how that changes as the current series of winter storms blows through).

And people have longer term concerns about what they’ve seen along the Tioga Road this season. The person who put it best is someone I did not talk to on my trans-Sierra excursion. Beth Pratt, a California outdoors and environment blogger, made a series of trips across Highway 120 during our weird winter idyll. Her enthusiasm and wonder for the spectacle she’s seen are infectious. But it’s also tempered by thoughts of the future:

“Bottom line: for a Yosemite and Sierra aficionado like me, having access this late is akin to winning the lottery. Of course when I have no drinking water next summer, I might feel differently. The lack of snow is alarming and the landscape is more reminiscent of spring than winter. Although it’s difficult to associate any one weather event or season to climate change, welcome to the Sierra Nevada of the future. I have seen predictions under the best case warming scenarios of an 80% reduction in snowpack. The Sierra can often deliver a wallop of a storm anytime of year, and I have no doubt we’ll recover at least some of the snow–this year at least. But this may be a warning from the ghost of the Sierra future.”

“Ghost of Sierra future?” Those words will stick with me. But for today, I’m glad to know that the snow’s flying again across the Tioga Road.

Danielle Hougard

Hard to imagine now: A snowed-over road near Lake Tahoe in March.

It was startling to see the state’s lead snow surveyor kneeling on bare grass near Echo Summit, trying to find enough snow to measure the water content. But so it went with the first official survey of the season, conducted by California’s Dept. of Water Resources.

The manual survey affirmed what remote sensors had already relayed — that water content in the Sierra snowpack stands at just 19% of the average reading for this time, right around New Year’s. The readings are just seven percent of where things usually stand on April first, meaning we have a long way to go, to get back to “normal.”

“The other discouraging thing is looking at the long-range weather forecast, that’s not encouraging either,” said Maury Roos, the chief hydrologist at DWR. He says with the season about one-third evaporated and no rain or snow in the forecast, there’s little encouragement on the horizon. “So if we lose half the month, then we’re down to trying to make it up in about half the season,” Roos told me by phone today.

CA Dept. of Water Resources

Key reservoirs are still in good shape, despite the lack of precipitation this winter.

At that particular spot where surveyor Frank Gehrke was scratching around for snow today, he logged a snow depth of four inches. That’s the least since the state started recording surveys of that snow course, in 1964.

The good news is that reservoirs are still rippling with runoff from last year’s epic snows in the Sierra Nevada. Two key Northern California reservoirs, Shasta Lake and Lake Oroville, are at 106% and 114% of historical averages, respectively. Roos says he estimated that this “carry-over” of water storage from last year could perhaps offset as much as 20% of this winter’s shortfalls. But the rest would still have to be made up in additional precipitation with what’s left of the “wet” season. “If it’s a real duster,” Roos told me, “There are still gonna be problems.”

Those problems would present in the form of water shortages during the summer. State water managers say their preliminary estimate is that towns and farms served by the State Water Project can expect 60% of the water they’ve requested to be delivered — but they hasten to add that weather conditions can change that figure dramatically, as they did last year when an initial 25% estimate swelled to 80% by winter’s end.

A white fir outfitted with snow sensors in the Southern Sierra Critical Zone Observatory. (Photo: Sasha Khokha)

It’s a patch of forest at about 6,000 feet near Shaver Lake in the Southern Sierra, in what’s known as the rain-snow transition zone. The snowpack at this elevation is likely to be the first to reflect climate change as temperatures warm and snow turns to rain. Scientists at UC Merced’s Sierra Nevada Research Institute, in conjunction with UC Berkeley, have developed new, high tech sensors to intensively monitor snow melt and runoff here.

The idea of remote sensors isn’t entirely new.  The state snow survey uses some 125 automatic sensors across the whole Sierra. But this project packs a two-square-kilometer area with more than 50 sophisticated snow sensors that transmit wireless data using cell phone technology. They also measure about a dozen factors, like solar radiation, humidity, and soil moisture. You can see them, and a single tree wired with about 400 sensors, here in this photo slideshow.

This high-tech surveying sounds like a good idea, even to the guy who’s built his career doing snow surveys the old way: slogging up mountains to slide a metal pole in the snow.

“We can’t just rely upon technology and procedures developed 100 years ago and expect them to necessarily serve us well in today’s age,” said Frank Gehrke, who heads the Cooperative Snow Surveys for California’s Department of Water Resources.

Gehrke admits that “guesstimates” based on taking manual samples don’t really give us a truly accurate picture of how much water the mountains hold.

“To try to take those point measurements and attempt to compute the total volume of snow water equivalent in a given basin is really a fool’s errand,” he said. “It just simply doesn’t work.”

But it wouldn’t work to put these new wireless gizmos across the entire Sierra Nevada, either. The goal is to focus on a few critical study areas to help get a more nuanced model of the snowpack in different kinds of environments. Scientists have started installing a cluster of instruments in the American River Basin, above Folsom Dam.

For more on the technology of snow surveys present and future, listen to Sasha’s radio story on The California Report.