.
In this Performance Task, you will answer five questions.
Something very interesting happened to the climate of the West Coast of the United States after the last ice
age, which occurred about 10,000 years ago. Before the ice age, the Southwest United States had an
abundance of plant life and was home to large fauna such as saber-tooth cats and mammoths. The Pacific
Northwest was mostly grasslands.
After the ice age, the jet stream that was responsible for pushing wind and moisture to the Southwest shifted
north as the glaciers retreated and showered the Pacific Northwest with precipitation. This led to the dense
forests that now cover that region, and a drying-out of the Southwest.
6.
How is climate defined? Do the events described constitute a change in climate for the West Coast of
the United States?