|
|
 |
How sand is carried
along Washington's southwest coast
Summer:
During the summer, winds come from the northwest; sand moves south.
Winter: During the winter, winds come from the southwest; sand moves north. Because winter winds blow harder, the dominant drift direction is north.
For several thousand years, floods washed sand to the mouth of the Columbia River, where it collected in shoals. Longshore currents shuttle sand from these shoals, carry it along shore, and deliver it to beaches.
Within the last century, the movement of sand from the Columbia River has been altered by dams, jetties, and other development.
|
 |
|
