From NCPA

The Cascade Mountain
snowpack in Washington and Oregon has supposedly declined 50 percent
since 1950.  That alarming statistic has taken on a life of it’s own in
the Northwest. The problem is Northwest scientists say it’s not
accurate. But when a leading researcher tried to set the record
straight, he lost a prestigious appointment.

It started with an
op-ed in the Seattle Times last month by Seattle mayor Greg Nickels. In
it, he cited the 50 percent decline in Cascade snowpack since 1950.  A
shocking wake-up call to water-users, skiers and utilities.  But what
if it’s not true?

According to Dennis Hartmann, chair of the atmospheric sciences department at the University of Washington:

  • That
    number is based on the period from about 1950 to 1995, which is a
    period during which there was a very large decline which was mostly
    caused by natural variations; in other words, natural weather cycles
    melted the snow not human-caused global warming.
  • Furthermore,
    since 1995 the average snowpack has increased in the Oregon and
    Washington Cascades; so he concludes the overall decline is more like
    30 percent; but when you adjust for nature’s normal ups and downs —
    that number is even smaller.

“A reasonable statement about
the part that we think is attributable to the warming associated with
global warming is probably more like 15 percent,” says Hartmann.

“The
50 percent was a misunderstanding that arose back in 2004,” says Philip
Mote, Washington’s state climatologist. “I tried very hard to squelch
it. And to explain that’s not correct.”

Instead, Mote says, it
took on a life of its own.  Until last month.  That’s when Mote’s
deputy in the state climatologist office — Mark Albright — started a
campaign to debunk the myth.  Earlier this week Mote fired Albright as
associate state climatologist — an upaid, but prestigious position.

Source: Austin Jenkins, “Scientists Say Cascade Snowpack Has Not Declined 50% Afterall,” KUOW.org, March 15, 2007.