Pacific NW Snowpack At Critically Low Levels

[hatrack]

"After one of the driest Februarys on record, accumulations of mountain snow have dropped even further below normal across much of Oregon, Washington and Idaho. That snow is a vital natural reservoir for the streams and rivers that supply irrigation and drinking water, produce electricity at hydropower dams -- and sustain wild salmon journeying to sea.

Last month brought one-fifth to one-third the average rain and snowfall to most river basins in Oregon. For Portland, it was the fourth-driest February on record. The lack of moisture, combined with warmer-than-normal temperatures, left snowpacks worse off than they were a month ago in most of the region. Washington is down the furthest, with a statewide snowpack at 27 percent of normal, compared with Oregon at 35 percent of normal.

The next month will be crucial. The winter's accumulation of rain and snow typically peaks in April, effectively setting the amount of water available as river runoff until autumn rains restart the cycle. Without a significant increase in precipitation, the region probably will face widespread summer water shortages and conflicts over the needs of people and wildlife.

"What we need to hope for is some wet weather this spring," said Andy Bryant, a hydrologist with the National Weather Service in Portland. "A month or two can still make a huge difference." Unfortunately for the water-supply outlook, forecasts by the weather service's national climate prediction center call for warmer and drier-than-average weather to persist through March."

EDIT

http://www.oregonlive.com/environment/oregonian/index.ssf?/base/news/1109681768138990.xml

[Squatch]

1. Ugh...I recall when I was a boater up in Seattle...

we would really cringe at the prospect of a short WW season based on the snowpack in the Cascades.

I did read a thesis in the latest "Nature" journal that showed that longterm snowpack is actually showing signs of positive growth in parts of the Cascades and Olympics. I think I still have that magazine, so I'll be sure to cite the research when I get a chance.

[Squatch]

3. Shit, I lied. Here's the piece I was referring to, but it looks as if

I was a bit mistaken in the findings.

-------------------

Bulletin of the American Meteorological Society: Vol. 86, No. 1, pp. 39–49.

DECLINING MOUNTAIN SNOWPACK IN WESTERN NORTH AMERICA*
Philip W. Mote

Climate Impacts Group, Center for Science in the Earth System, University of Washington, Seattle, Washington

Alan F. Hamlet

Department of Civil and Environmental Engineering, and Climate Impacts Group, Center for Science in the Earth System, University of Washington, Seattle, Washington

Martyn P. Clark

Center for Science and Technology Policy Research, University of Colorado/CIRES, Boulder, Colorado

Dennis P. Lettenmaier

Department of Civil and Environmental Engineering, and Climate Impacts Group, Center for Science in the Earth System, Seattle, Washington


ABSTRACT

In western North America, snow provides crucial storage of winter precipitation, effectively transferring water from the relatively wet winter season to the typically dry summers. Manual and telemetered measurements of spring snow-pack, corroborated by a physically based hydrologic model, are examined here for climate-driven fluctuations and trends during the period of 1916–2002. Much of the mountain West has experienced declines in spring snowpack, especially since midcentury, despite increases in winter precipitation in many places. Analysis and modeling show that climatic trends are the dominant factor, not changes in land use, forest canopy, or other factors. The largest decreases have occurred where winter temperatures are mild, especially in the Cascade Mountains and northern California. In most mountain ranges, relative declines grow from minimal at ridgetop to substantial at snow line. Taken together, these results emphasize that the West's snow resources are already declining as earth's climate warms.

*Joint Institute for the Study of the Atmosphere and the Ocean Contribution Number 1073

[rustydad]

2. Predicted

This is exactly as predicted by a report from the National Academy of Science in their August 04 edition. A link to the PDF Report is here. Bob

http://www.pnas.org/cgi/content/abstract/101/34/12422