Sierra Nevada

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Scientists Look for Climate Trends in High Places

Molly Samuel

Scientists gather on Freel Peak to take a census of the plants on the summit.

Mountaintops can be good places to study the effects of climate change because there aren’t any things like factories or highways or garden weeds up there. In that way, they’re more like laboratories.

So, even though it involved a tough hike, about a dozen scientists gathered at the top of Freel Peak near South Lake Tahoe earlier this summer to count every single plant at the summit. It was for GLORIA, short for Global Observation Research Initiative in Alpine Environments, a project that sends botanists and plant ecologists to the world’s highest mountains to document the tiny, colorful plants that live on them.

GLORIA surveys are repeated every five years, and this was the second survey on Freel Peak. By tracking the changes here, scientists can gain a better understanding of how alpine regions differ in their responses to climate change, and what the future may hold for lower elevations.

“Because of the nature of the alpine habitat, it is more sensitive to environmental changes,” explained GLORIA coordinator Colin Maher. “It’s kind of a beacon. It’s like a warning sign. We might not know for 20 years what’s happening, but it’s a place where change is more likely to happen and we can detect it.” Continue reading

Forget this Winter: Western Snowpack Shrinking

By Alyson Kenward

A new study finds large losses of springtime snow cover in the West in recent years, raising concerns about water supplies.

Spring snowpack in the West is an essential water resource, particularly in Southwestern states that are prone to summer drought, like California, Nevada, Arizona and New Mexico. (Credit: Wolfgang Staudt on Flickr)

This spring, from the Pacific Northwest and Sierra Nevada, to the Northern Rockies, western mountain ranges were more than just snow-capped – they were buried in the white stuff. In fact, many locations still have more spring snowpack than has been seen in decades.

Head south across the 40th parallel, however, and things are dramatically different. While there is still above average snow throughout the Sierra, a relatively snow-less winter and spring has left much of the Southwest in a drought that has fostered record wildfires. Already local officials are worried there won’t be enough water to get through the summer months ahead. Continue reading

Burgeoning Snowpack Sweetens Water Outlook

A wet and wild February provided a huge boost to California’s water outlook

An unusually dry January started some folks thinking that maybe the tap had been shut off for this season. But last month winter came roaring back as Pacific storms brought epic snowfalls to the Sierra. The result: Today’s monthly survey shows the water content of the mountain snowpack at 124% of normal for this date–and even above its normal level for April first.

Check current reservoir levels with our interactive map, below.

Major reservoirs are also above their normal levels for early March. But it still doesn’t mean that contractors on the State Water Project will get all the water they ask for. Officials say they still expect deliveries to come in at about 60% of the volume requested. That’s a number that typically gets adjusted throughout the winter. Continue reading

Playing the State Water Lottery

Craig Miller

Photo: Craig Miller

I don’t know Mark Cowin, the director of the state’s Department of Water Resources. I haven’t even met the man, in person. But after listening to and reading his pronouncements about the state’s water supply, I’d guess he’s a guy who would barely crack a smile if he found himself holding a winning lottery ticket. I hazard that opinion because even after today’s great news about the Sierra snowpack–which is a little like finding out the state has won its annual water lottery–what Cowin emphasizes is that California isn’t out of the woods after the dry spell of 2007-2009. But more about that to follow. First, the details on the DWR’s final Sierra snow survey.

DWR announced on Friday that statewide, the water content stored in the Sierra snow is at 143% of normal for the date; 188% in the northern Sierra, 121% in the central mountains, and 139% in the southern reaches of the range. Up and down the Sierra, those figures are more than double the levels of the past two years, and are up to seven times as much as surveyors found in the bone-dry spring of 2007.

Last week, the Department announced it would increase allocations from the State Water Project to 30% of the amount requested from 29 urban and agricultural customers. Today’s snowpack news prompted the department to say that it’s likely to increase deliveries. How much? “Only marginally,” Cowin said in a phone interview this afternoon. “We’ll have to run the numbers, and we’ll probably make that determination in the next week or two.”

How much water will State Water Project customers get, eventually? Let’s run some numbers of our own.

The main reason the department cites for the very tight supply in the midst of a year of “normal” precipitation is the continuing below-average levels at California’s biggest state-owned reservoir, Lake Oroville. As of Friday afternoon, the lake is at 72% of normal for the date and about 60% full. But the stats that Cowin’s water geeks are crunching aren’t about the level today, but where they guess it will be as runoff begins to pour from the snow-blanketed mountains through the Feather River watershed into Lake Oroville. DWR officials have insisted that it believes runoff will be held down because of dry conditions caused by the last three drought years. You wonder if they’ll still believe that after assessing the impact of an unusually wet April and its impact on the snowpack.

While pondering that, here are some other numbers to consider if you want to play what I’ll call the State Water Project Allocation Game:

  • After running far below its 2008-2009 levels all season, the water storage in Lake Oroville caught up and passed year-ago levels this week. The lake’s storage has increased six percent—more than 150,000 acre-feet—since last Friday.
  • As noted above, this year’s snowpack is better than double last year’s.
  • Last year, the state delivered 40 percent of requested water shipments to its SWP customers. The average allocation for the past 10 years is 68 percent.

Considering all of the above—last year’s deliveries, the snowpack, the sudden late-season surge in Lake Oroville’s levels—it’s a no-brainer that water deliveries will at least match last year’s 40 percent. The question is whether the allocation will go higher. All Cowin would say on that subject today is that he thinks that 45%, the amount DWR described two months ago as the upper limit for shipments this season, is still accurate.

But Cowin did say, as he has more and more frequently of late, that a preoccupation with the this year’s water level misses the point about California’s water reality.

“That’s why we’re so concerned when we get the black and white question, ‘Is the drought over,'” he said. “We are in a period of long scarcity in California. We have no idea what next year’s water supply picture will look like. It’s possible we could have two or three more dry years in a row. So we’re trying to get a message out that we need to have a new attitude about how we use water in California, and it shouldn’t depend on this week’s outlook. We need to conserve water just as a way of life.”

If you want to explore the state’s water supply picture for yourself, check out our California Reservoir Watch map, below:

View KQED: California Reservoir Watch in a larger map
View KQED: California Reservoir Watch in a larger map

What’s an Albedo? (And Why You Should Care)

Jeff Dozier approaches the instrument tower on Mammoth Mountain.

Jeff Dozier approaches an instrument tower on Mammoth Mountain. Photo: Molly Samuel

When Jeff Dozier, a hydrologist at UC Santa Barbara, goes to work, he gets to enjoy quite a view. His snow lab is perched halfway up Mammoth Mountain in the central Sierra. We took a gondola to get up there; the other passengers were skiers and snowboarders itching to get out on the freshly fallen snow.

But the instrument platform from which we enjoyed views of the White Mountains is really only half the story. Dozier’s computer lab has much less of a view. In fact, it has no view. It’s buried under the snow, accessible only through what he calls a “Santa Claus entrance” (in the picture above, you can see the entrance–it’s the white tubular “chimney” extending down into the snow from the center of the platform).

The snow lab, operated by both UCSB and the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL), uploads information about the snowpack to a website every fifteen minutes. You can see nearly real-time readings on, among other things, snow depth, temperature, humidity, and radiation.

Dozier in the computer lab. Photo: Molly Samuel

Dozier in the computer lab. Photo: Molly Samuel

Radiation is an important one. Instruments called radiometers are mounted on the tower. Some point up, measuring the radiation coming from the sun; others point down, measuring how much is reflected back to the sky by the snow.

Albedo” is the measurement of how reflective the snow is. Something completely white that reflects all of the sun’s energy has an albedo of one; something black, that absorbs all the energy, is zero. Bright, freshly fallen snow has a high albedo, typically above 0.8.

Even if the term is new to you, albedo is probably a familiar concept. As I reported for KQED’s The California Report this morning, Hans Moosmuller of the University of Nevada’s Desert Research Institute explains it in terms of outfits: on a sunny day, if you wear a black sweater you’ll be warmer than if wear a white one. You may notice it with roofs, too. I grew up in Atlanta, in a house with a black roof. Before my parents got an air conditioner, the upstairs bedrooms were unbearable in the summer. If we’d had a white

These radiometers measure radiation coming from the sun. Photo: Molly Samuel

These radiometers measure radiation coming from the sun. Photo: Molly Samuel

roof, it would have been a little more bearable (though I can’t say it would have helped with Atlanta’s other charming summer attributes, humidity and mosquitoes).

The color sweater you wear has no bearing on the earth’s climate. Roof color could have an effect on a large enough scale. What really matters are the huge swaths of dark and light that cover the globe: ocean and snow.

When warming causes sea ice near the poles to melt faster, areas that had a high albedo (ice is very reflective) become  areas with a very low albedo (the blue ocean absorbs more radiation than forests or plain dirt). Moosmuller says it creates a feedback loop. The more dark spots there are, the more radiation is absorbed. So melting speeds up, and warming increases, exposing even more dark areas, and so on.

Pollution plays an important role that’s coming under increasing scrutiny. Deposits of soot or dust make the snow darker, so it melts faster, exposes more dark ground, and there’s that feedback loop again. In the Himalayas soot, also known as black carbon, from stoves, tailpipes, factories, and fires is having a measurable impact.

In the Rockies, there’s a similar problem caused by dust kicked up from ranches. Tom Painter of the University of Utah says the snow in the Colorado River Basin melts a full month earlier than normal. The difference the dust makes is so drastic, Painter says, that “We’re in an entirely new regime for snow melt…it would be like if we started measuring climate impacts fifty years from now.”

No one has yet done a long-term study on the effects of dust and soot on the Sierra Nevada snow pack. Moosmuller says he’s beginning to look into it now. In the summer, black carbon drifts into the mountains from California’s cities, ports, highways and farms in the Central Valley. Tony Van Curen, in a research project at UC Davis, has found that soot blows over from Asia, too.

There is good news in all of this: Black carbon, unlike most greenhouse gases, lingers in the atmosphere only for a couple of weeks. So reducing emissions could have a relatively quick impact.

Listen to the radio piece.

(Some) Pika Persist at Low Elevations

Photo courtesy of the Forest Service.

Photo: US Forest Service

American Pika are living at lower elevations and surviving warmer temperatures than previously thought, according to a paper in the journal Arctic, Antarctic, and Alpine Research (available for download at the US Forest Service Pacific Southwest Research Station’s site).

One of the authors, Connie Millar, said she saw pika far more often and in a broader elevation range than she had expected she would. Millar, a Forest Service ecologist, found all those pika using a method she developed to quickly determine if pika are living in places where one would expect to find them.

Pika, cute little rabbit relatives that live in high elevations throughout the West, have been in the news lately. The Center for Biological Diversity (CBD) petitioned for the pika to be listed under the federal Endangered Species Act in 2007, citing climate change as a threat to survival of the cold-adapted species. Last month, under a new administration, the U.S. Fish and Wildlife Service decided not to protect the pika, explaining that though some populations do seem to be in trouble, most are doing fine so far. (Climate Watch has followed the pika story; see previous posts here, here, and here).

This newest study would seem to support the federal decision. But Shaye Wolf, staff biologist with the CBD, says that though the study “provides a snapshot of where pika are now, long-term in-depth studies have found that pika populations are declining.”

The majority of those declining populations are in Nevada’s Great Basin, at relatively low elevations for pika colonies. One paper Wolf cites was recently published in Ecological Applications. Authors Erik Beever and Chris Ray concluded that shrinking pika populations in the Great Basin could be partially attributed to climate change. Pika have an extremely narrow band of temperature tolerance and can suffer heat stroke in temperatures comfortable to humans.

Wolf and Millar are both members of the California Pika Consortium, a newly formed research group. Millar plans to distribute her pika survey to colleagues in the consortium in order to continue gathering data on locations of pika colonies.

Meanwhile, even though the Fish and Wildlife Service has denied federal protection to the pika, CBD is still working on gaining state-level protection in California. CBD biologists consider the pika to be a bellwether species for climate change.