Hot Creek, near Mammoth Lakes, was one of 20 streams in the Western U.S. examined in a study by Oregon State researchers who found no clear relationship between increasing air temperatures and stream temperatures.
Rising sea levels, melting glaciers, intensifying storm events – evidence is mounting that the effects of a warming planet will be far-reaching and potentially catastrophic. But one natural system may be more resilient than others when it comes to global warming: mountain streams.
Water temperature is a critical variable for aquatic ecosystems. Some fish, for example, time egg-laying to minute changes in water temperatures; in other species, stream temperatures are a key factor in determining the sex of juvenile fish. Continue reading →
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 →
As if drought and wildfires weren’t enough, California’s coniferous forests face another climate-related threat
(Photo: Reed Galin/Lone Tree Productions)
In the last decade, tiny forest-dwelling beetles have wiped out pine trees on millions of acres in the Canadian and American West, including Southern California. The rest of the state has been largely spared, but forest ecologists say that’s likely to change.
Reporter Ilsa Setziol recently spent some time tracking these bugs with an entomologist from the US Forest Service. They found beetles at work in Jeffrey pines and coulter pines in the San Bernardino National Forest, east of Los Angeles. Continue reading →
Frank Gehrke conducting last year's first snow survey of the season. (Photo: Gretchen Weber)
All the wet weather that’s been drenching much of the state has left the Sierra Nevada with an extra-thick blanket of snow, which has water officials optimistic about the state’s water supply for 2011.
Using a combination of manual and electronic measurements, the state’s Department of Water Resources conducted its first snow survey of the season on Tuesday, and found the water content of the state’s snowpack at 198% of normal for this time of year. Last year at this time, the statewide average was just 85% of normal. Continue reading →
If you’re counting on water from the State Water Project, this year is at least starting off better than the last couple.
For the farms and towns that depend on deliveries from the SWP, the outlook for the coming year is better than in recent years, which is not to say ideal.
State water managers today made their preliminary estimate that customers would get one quarter of the water requested from the system. That beats last year’s initial estimate of five percent–the lowest on record. Mark Cowin, who heads the state Department of Water Resources, says these early estimates are intentionally stingy:
“Over the past few dry years, CA has made good progress in improving our ability to conserve water,” Cowin told reporters in a conference call today, but cautioned that “We must continue to promote an ethic of using water efficiently—regardless of the day-to-day outlook for water supplies.”
But Cowin says that between the wet spring and early start to the rainy season this fall, chances are good that the initial 25% projection will rise.
A key reservoir on the system, Lake Oroville, stands at more than three-quarters of its average for this time of year, whereas last year at this time, it was only about half full. By the time the water year was winding up, DWR officials had raised the allocation to 50%. They added that with average precipitation the rest of the way, customers could end up with about 60% of their hoped-for deliveries in 2011. So far this season, precipitation is running ahead of the long-term average.
Water in the State Water Project, like the federally run Central Valley Project, comes in large part from the mountain snowpack of the Sierra and lower Casdade ranges. Growers typically make up for shortfalls by pumping more groundwater.
The decrease in snowpack would be driven by two processes, according to study author Geoffrey Schladow. With warmer temperatures, more precipitation will fall as rain during the winter, instead of snow. And as any skier knows, when rain falls on snow, it melts the snowpack in what scientists call “rain-on-snow” events.
These findings are a concern since the Sierra Nevada snowpack is often called California’s “frozen reservoir.” That reservoir is critical to the state’s water supply — and it’s free. “What the snowpack affords us is a way to very economically store water,” said Schladow. “If the water is falling as rain, rather than snow, then we have to build more dams and reservoirs to catch it, which is expensive.” Continue reading →
As the world warms, officials at the National Park Service are starting to sweat: No glaciers at Glacier, no Joshua trees at Joshua Tree. These are part of the long-range forecast for the national parks.
A misty Lake McDonald in Glacier National Park; metaphor for the park's murky future? (Photo: Craig Miller)
Last month, in a post from Glacier National Park, I noted that Park Service director Jon Jarvis was not in a mood to mince words, calling climate change “the greatest threat to the integrity of the national park system that we’ve ever faced.”
That assertion was underscored last week in a new report on potential impacts to the parks from climate change. The collaboration by the Natural Resources Defense Council and the Rocky Mountain Climate Organization, attempted to zoom in on specific parks and projected changes ahead for ten national parks in California, as well as impacts on the state’s economy.
Death Valley is already the hottest spot in North America. The highest recorded temperature there is 136 dF. (Photo: Craig Miller)
Some conclusions under a “medium-to-high” emissions scenario, toward the end of this century: Higher temperatures in Joshua Tree National Park would mean the end of, well, Joshua trees in the park. Muir Woods could be as warm, on average, as San Diego has been historically, making it less hospitable to the park’s legendary coast redwoods. Death Valley, already the hottest spot on the continent, could become virtually uninhabitable during the summer, as average temperatures rise by more than eight degrees, Fahrenheit, over average readings from 1961 to 1990. Continue reading →
Renewable energy developers will get no special treatment in the National Parks, according to National Park Service Director Jon Jarvis.
National Park Service Director Jon Jarvis at McDonald Creek, Glacier National Park (Photo: Craig Miller)
Jarvis made the comment yesterday while touring Glacier National Park in Montana, with members of the Society of Environmental Journalists. “Renewables do not get a free ride,” said Jarvis, when asked about how the parks would treat development of renewable energy sources on park property.
Using the backdrop of Glacier National Park, where the remaining 25 glaciers (out of an estimated 150) are expected to disappear by 2030, Jarvis called climate change the most serious threat ever posed to the integrity of the park system. Continue reading →
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:
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).
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
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.