These photos (below) are from a website run by NASA called Earth Observatory, which features satellite photos and pictures taken by astronauts from Earth orbit. They show how a warming Arctic is affecting glaciers. But, I also found these photos interesting because it helps me imagine and understand what happened in the Seattle area during the ice ages.Puget Sound is also a fjord, and we all learn in grade school that it was carved by glaciers, and that the glaciers were once a mile thick above downtown Seattle. When those glaciers melted and retreated they left steep hillsides, lakes, and a deep watery trench.
The channels that look like rivers would be like the channels between Seattle or Tacoma and Kitsap.