Wonder what the weather will be like in Western Washington 50 years from now?
Climatologists say we’re experiencing a sneak preview now.
Winter 2014-15 — regarded by many as almost freakishly warm and snowless — will be the new normal, if climate change continues as expected.
The basic combination projected for the Northwest by climate models — higher temperatures and about average precipitation — has had a dramatic effect in the Cascades and Olympics. There’s almost no snow.
“Snowpack is dismal, the forecast is grim, but precipitation is bountiful,” state drought response coordinator Jeff Marti told scientists and policymakers gathered this month in Olympia to assess the likelihood of summer water shortages.
Water managers say one snowless year is not likely to cause dire consequences for either drinking water supplies or power generation in heavily populated areas of the state this summer, thanks mainly to extra reserves of water in reservoirs.
But because low-snow winters like the one just ended are expected to gradually become routine during the next few decades, scientists, fisheries managers, farmers and public utility forecasters are taking a keen interest in how the environment reacts.
RECORD OR NEAR-RECORD LOWS
Just how little snow there is in the mountains is obvious from snow telemetry maps prepared daily by the Natural Resources Conservation Service.
More than 27 percent of snow telemetry reference stations in Washington are setting record low or near record lows for snow at this time of year.
Scott Pattee, water supply specialist for the Natural Resources Conservation Service, said surveyors are able to drive vehicles to telemetry sites normally accessible only by snowmobiles.
Interstate 90, which crosses the Cascades at Snoqualmie Pass, has not been closed for avalanche control this season. Cayuse Pass is expected to open Friday and Chinook Pass on April 3.
That’s the earliest ever for Cayuse and ties the record at Chinook.
The telemetry data show snow levels in river basins that drain into the South Sound are at less than one-quarter of normal levels.
In the Central Cascades and on the Olympic Peninsula, the snowpack is even lower — just 6 percent of the median level over the past 50 years in the Central Cascades and 11 percent in the Olympics.
On Mount Rainier, which set world records for annual snowfall in the 1970s with nearly 100 feet of snow in single seasons, patches of bare ground are in spots where melt-out usually doesn’t occur until June or July.
Last year started out as a low snow year, too, but heavy springtime precipitation and cool temperatures brought snow levels up to near normal.
Weather forecasters say a repeat of that recovery would be almost impossible this year. The meteorological winter is over, meaning we’ll almost certainly see no more flooding storms. Long-range forecasts call for higher-than-normal temperatures for the remainder of this month and next.
Most large power and water systems in Western Washington say they’re adequately prepared for the summer because they’ve been stockpiling water in reservoirs to make up for the lack of snow.
Snow is a natural water reservoir in Washington. As it slowly melts in the summer, it supplies a steady supply of water downstream.
Water managers do the same thing with reservoirs. They collect water in late winter and then parcel it out over dry spring and summer months for fish, irrigation, power generation and drinking water.
“Storage is the compensating factor in terms of hardship issues,” said Marti, the state’s drought response coordinator.
Many reservoirs in Washington are holding onto significantly more water than usual, according to the most recent Natural Resources Conservation Service’s National Water and Climate Center report.
On March 1, 11 reservoirs in the state reported nearly 2.5 million acre feet of water, about 12 percent more than average. (One acre-foot of water is equivalent to 326,700 gallons.)
The reservoir behind Cushman Dam, one of seven dams Tacoma Public Utilities uses for power generation, is about 20 feet higher than usual.
“We don’t anticipate any negative consequences,” said Chris Gleason, the utility’s community and media services manager.
“We’ve been storing water in our reservoirs and, from a customer impact point of view, we aren’t predicting any problems. No rate changes,” Gleason said, “In general, we’re in pretty good shape.”
The city of Olympia isn’t expecting any problems either.
Olympia gets its water from wells — mostly the McAllister well field near the Nisqually River east of Lacey — and groundwater levels are at reassuring levels, according to the city’s Public Works Department.
“Precipitation has been normal and the soil is saturated,” said Andy Haub, Olympia’s water resources director. “We should be fine.”
At Howard Hanson Dam, at the headwaters of the Green River, water managers are not sounding so positive.
Water stored behind the dam is used to provide water to Tacoma and to increase river flow to help protected species of fish, including chinook and steelhead.
The U.S. Army Corps of Engineers, which manages Howard Hanson, began topping off the reservoir in February, a process that usually takes three months.
The near absence of snowpack in the Green River Basin means it’s taking longer to fill the reservoir, Corps senior water manager Ken Brettmann said. There’s a good chance, he added, that the river’s flow will be well below average this spring.
That wouldn’t create a water shortage in Tacoma, he said, because the city has other river water sources and, if necessary, it can tap into its own wells, fed by healthy aquifers.
It’s possible, though, that lower flows — and consequently, higher water temperatures — could affect fish habitat.
As the effects of global warming continue, Brettman said, and lower snowpack becomes routine, filling the reservoir will be more difficult in years when it doesn’t rain much.
“The way it works at Howard Hanson is, the snowpack is the insurance policy,” he said. “In the future, we might have to rely more on the rain.”
Puget Sound Energy, which relies on hydropower for about 41 percent of its energy mix, is not ruling out the possibility of rate increases because of the low snowpack.
“We’re seeing statewide totals, on average, about 29 percent of what they should normally be,” company spokeswoman Akiko Oda said. “In the Baker basin — which feeds into our reservoirs and two dams there — that amount is even lower, between 22 to 26 percent of normal.
“There are some places at 3,500 feet where there’s no snow at all, and they would typically have 90 to 100 inches,” Oda said. “The low water flow totals could impact hydroelectric generation, and we’re paying very close attention to that. If the conditions stay on the dry side, we’ll be more cautious about generating too much hydropower in the spring.”
BARREN SLOPES AT RESORTS
The group most obviously suffering from low snowpack in the Cascades is the ski industry, for which the lack of snow made a mess of this year’s season.
The Crystal Mountain Resort, largest ski and snowboarding area in the state, reported a snow depth of just 2 inches on lower slopes last week and less than 4 feet on upper slopes. Just two of Crystal’s 11 ski lifts were operating.
“This was probably the worst year we’ve ever had,” said Tiana Anderson, Crystal’s marketing director.
Stevens Pass, at least temporarily, suspended operations last weekend after a drenching rainstorm ate away at what little snow remained.
WORRIES ABOUT WILDFIRES
Tree tops and bushes poking up through the snow at ski resorts are obvious. Less so are the effects of low snowpack on plants and animals.
While rainfall efficiently recharges groundwater in some areas, others are left high and dry in low snow years. Wetlands dry up and animal reproductive cycles are disrupted.
Forests are more susceptible to drying out, raising concerns about fire. Already, state emergency management officials are worrying about another above-average wildfire season.
Last year, the Carlton Complex fire in the Methow River Valley in Okanogan County grew into the largest wildfire in state history, covering more than 250,000 acres and destroying more than 300 homes.
The winter’s lack of snow increases the potential for forest fires this summer — especially at higher elevations — but other weather factors are at least as important, said David Peterson, a research forester with the U.S. Forest Service’s Research and Development office in Seattle.
Low snowpack doesn’t automatically result in more fires, Peterson said, but it contributes to danger when combined with other factors. Extended periods of hot, dry, windy weather and lightning strikes further elevate the danger, he said.
Because higher elevation forests have rarely, if ever, burned, he said, they contain large amounts of fuel.
“You can imagine a table where a few matchsticks are scattered across it compared to one with piles of matchsticks,” he said. “It’s easy to understand where the fire would be more intense.”
Peterson and other forest researchers say one year of unusually low snowpack does not present much of a problem for forests in and of itself.
“These trees have been around for thousands of years,” he said. “They’ve evolved to deal with short-term stress.”
What’s more concerning from an environmental point of view, he said, is that this year’s weather is likely to become typical in coming decades according to climate model predictions.
“Statements about this being the new normal of 2060 or 2070 are probably very accurate,” Peterson said. “Then we’ll start pushing these forests’ resilience to stress. It opens up their susceptibility to insects, pathogens, fungus and nonnative species.
“We tend to think of stresses and disturbances one at a time,” he said. “But if we start stringing them together, they’ll have an additive effect.”