Why 80% of Americans Live East of This Line

Summary by Krater

This video examines why North America's human population and precipitation levels are sharply divided along a North-South line, exploring historical geographic insights, climate science, and water scarcity issues in the western United States.

From the video

Answers: Why is the human population in North America split down the middle?

• population density in North America
• the 100th meridian and 98th meridian
• annual precipitation levels in the United States
• geographic rain shadow effect of mountain ranges
• water scarcity and irrigation in the American West
• John Wesley Powell's historical proposals

What it concludes

• 80% of Americans live to the east of the 98th meridian line.
• The 98th meridian sharply divides the American population and annual precipitation levels in half.
• The Rocky Mountains and Cascade Mountains create massive rain shadows, blocking moisture from reaching the western interior.
• The 100th meridian line of longitude, identified by John Wesley Powell, historically marks the boundary between the wet East and arid West.
• The arid/wet boundary line has steadily shifted eastward towards the 98th meridian over a century and a half due to global climate change.
• The Colorado River is experiencing unprecedented drying, leading to federal water cutbacks for states like Arizona and Nevada.