The whole west coast is a desert, both sides of the Cascades, some areas just get more rain than others. All the soils are volcanic. The two places I know that have limestone deposits are the Lake Shasta region, and out beyond Pendleton, Oregon.

During the last Ice Age, there were no glaciers on the Alaskan coast. There is evidence of tsunamis, but it is explained as being the remnants of glaciers. Ross Island Sand and Gravel which used to operate off the east side of both the Sellwood Bridge and the Ross Island bridge in Portland, has an abundance of round stones including agate. It closed because it mostly made Ross Island dissapear. Everything they sold was very much rounded indicating extensive river erosion.

I believe we are seeing a return to the Ice Age weather patterns, where moisture no loner goes east over the Cascades, but instead goes north to above the Arctic circle, then makes snow as it drifts east, over both Canada, and eventually the Great Lakes region. Windy.com will show where the prevailing winds are going.

It's a type of climate change, but not what AL Gore is promoting.