Mount Rainier, Washington.

A new study from the University of Washington suggests that there is no clear evidence that human-induced global warming has caused a drop in 20th century snow levels and that the volcanic, mountain chain could enjoy a delay in the future effects of global warming, according to an article from the Seattle Times.

Here is a link to the powerpoint presentation of the study. By the way, the first picture of the man skiing up to the roof of that building was the same hotel I stayed at during a visit several years ago on Mount Rainier. I am pretty sure that is the Paridise Hotel. When we went in July there was still many patches of snow up to a foot deep all around the grounds of the hotel.

Cliff Mass, a University of Washington meteorologist and co-author of this study says that studying the snowpack trends depends greatly on which years are examined. Mass and colleagues tried to estimate snowpack before the 1950's, a decade where snow levels were unusually high and the reason why we see a greater than 30% drop off in snow pack over the second half of the century when you use that decade as the starting line.

Mass and his team used a measurement that did exist before the 1950s: The amount of water that flowed down streams as snow melted. The team determined that the drop in snowpack from the 1930's through present time was 23%. (The 1930's in the U.S. was a warm decade, but I do not know if that was the case in the Cascades. It would be nice to know what the percentage drop was when you start out in the 1900's, 1910's or 1920's as well.)

Mass and colleagues say that many of these changes in snowpack are attributable to shifting weather patterns driven by the Pacific Ocean, which is what we heard from the Mount Shasta glacier report I blogged about recently.

The team also noted that computer models predict that the northeast Pacific will warm more slowly than most of the world's oceans, keeping the average rain/snow level from gaining altitude
too quickly.

Not so fast!

Alan Hamlet, a University of Washington hydrologist, who co-authored a study on snowmelt hydrology in the mountainous West back in 2005 disagrees with Mass. Hamlet says the snowpack trends during the second half of the century are consistent with rising temperatures which are tied to global warming. He also criticizes some of the statistical analysis of the new study co-authored by Mass.

You can read more about this story here..