Snowfall in the West will probably decline under climate change. Even in areas with more precipitation that moisture will likely come as rain. This is a big water rights question as many irrigators do not have storage and will likely not have much end of crop season water. Here’s a report from Brett Walton writing for Circle of Blue. Click through and read the whole post. Here’s an excerpt:
Famously overcast and stormy in the cold months, the Pacific Northwest is normally a haven for snow lovers. From volcanic peaks to valley basins, winter resounds with the glee of cherry-cheeked skiers and the terror of thunderous avalanches. Mount Baker, a mainstay of the Washington state ski circuit, is accustomed to skyscraping snow accumulations deep enough to entomb an 18-meter (60-foot) building.
Not this year. Record-warm temperatures expose bare mountain ridges and disappoint ski bums and lift operators alike. Despite average levels of precipitation, rain is falling, not snow. Snowpack in much of the Olympics, the remote Washington peninsula mountain range, and in the Cascades, the spine from here to northern California, is less than 30 percent of normal.
It is a worrisome development, say hydrologists. Snowpack acts as a natural reservoir, a bank of moisture that melts slowly and keeps rivers flowing through the heat of the August dry season when spawning salmon, big wheat fields, and apple orchards are most in need of water…
Snowless conditions in the Cascades this winter are a cautionary signal for the entire American West, which is undergoing a “major hydrological shift” from snow to rain because of higher temperatures, according to a paper from University of Idaho researchers published last July. Their analysis projects that the area in which temperatures are cold enough for snow in the 11 western states will decrease by roughly 30 percent by mid-century…
Water managers need to balance a constellation of competing interests, from hydropower generation and flood protection, to fish health, forest fire risks, and water supply to cities and farms. The old playbook for operating dams and reservoirs must be revised and adapted to the new hydrology, managers say.
To do so, they argue, local, state, and federal governments must continue a recent trend of investing in stream gauges and equipment that monitors river flows, snow levels, and weather patterns. These tools are the guide ropes that managers use to allocate water and prepare for droughts and floods…
Better Management through Better Data
On-the-ground data is the lifeblood of hydrological forecasting. Computer models that predict conditions up to a year in advance need to be calibrated and refined by comparing the model’s output with historical measurements. The region’s river forecast centers use stream flow information from U.S. Geological Survey monitoring networks and snow measurements from National Resources Conservation Service sites.
Both Seattle Public Utilities and the Bureau of Reclamation use forecasts from the Northwest River Forecast Center, one of 13 regional forecasting divisions of the National Weather Service. Yet even as the complexity of river forecasting increases, and hydrological cycles are more disrupted than ever before, the nation’s resolve to pay for data collection and analysis is in transition.
Two years ago, at the height of Congress’s drive for fiscal austerity, some 618 stream gauges were shut down by the U.S. Geological Survey and its local partners for lack of money. Federal dollars used to support half the cost of operating a jointly-funded stream gauge. Now, the federal share is down to 30 percent. National Water and Climate Center officials told Circle of Blue last year that they deferred maintenance of many snow-monitoring sites after a 15 percent budget cut in 2011 and a 7 percent retraction during sequestration in 2013.
Recently, though, Congress increased funding for the National Streamflow Information Program, which goes toward stream gauges, by $US 6 million in 2014 and $US 1.2 million in 2015, a 26 percent increase over two years. It was enough money to provide full support for 1,000 of the 8,100 monitoring sites in the national streamflow program. The remaining sites are paid for by state and local agencies.
“Congress is starting to get it,” Pixie Hamilton told Circle of Blue. Hamilton is the national coordinator of the Cooperative Water Program, a branch of the U.S. Geological Survey that facilitates data collection partnerships. “Congressional folks are understanding the value of stream gauges in their districts. Word is getting out that stream gauges serve multiple needs, and there is keen interest around the states and Congress to keep up these gauges.”
Still, there is room for improvement. The Cooperative Water Program’s budget — $US 59 million — has remained roughly the same for 25 years, cutting the real value of its funding in half because of inflation. More of the 4,759 gauges deemed a national priority could be supported by a full appropriation from Congress, and the federal cost-share for collaborative projects could be increased.
“We are creatures of the water cycle,” Fleming said referring to his water management colleagues. “The more we can enhance our knowledge and bring it into the decision-making, the better position we’ll be in.”
More infrastructure coverage here.