Jan 13, 2015

Raymond Shaw  Professor of Physics  BIO

Location:  Carnegie Museum Community Room,  Downtown Houghton

Times:   6:30 pm: Refreshments and introductions   7-8 pm:  Seminar and Discussion

Lake Superior in my driveway: lake effect snow in the Keweenaw

Whether you enjoy skiing, snow shoeing, or sledding, and in fact even if you simply endure the snow shoveling, lake effect snow is part of daily life in the Keweenaw for almost half of the year. Our peninsular home is surrounded by Lake Superior, which when conditions are right, becomes a giant snow-making machine. Just as the water in a pot on a hot stove overturns and mixes, the cold air blowing over relatively hot Lake Superior rises and forms banded patterns. The clouds that form in the updrafts contain millions of water droplets that remain liquid even below freezing temperatures. A few of those droplets are lucky enough to come into contact with relatively rare particles able to stimulate the freezing process, and those favored few ice crystals then grow rapidly and eventually fall from the cloud as snowflakes, accumulating on the ski trails and on your driveway... express delivery, straight from the big lake! Many mysteries remain about the details of lake effect snow, so come learn some of what we know and what we are trying to learn about this aspect of life in the Keweenaw.