Have you ever wondered why the eastern half of the United States is densely populated while everything west of Omaha, save for a few metro areas, is no man’s land?
Most people would assume that it’s because people first settled in the east and moved west. Or, they may believe it’s because of the vast desert that takes up most of the southwest. Those are some decent reasons, but it’s a much more complicated issue than you’d imagine.
A 20-minute video by RealLifeLore explains how topography and rainfall have created what appears to be a straight line down the middle of the country on the 98th meridian that dictates population density. Eighty percent of Americans live on the east side of the line and just twenty percent to the west.
In the video, we see that several large cities border the American frontier—San Antonio, Austin, Fort Worth, Oklahoma City, Wichita, Omaha, Lincoln, Sioux Falls and Fargo, as well as Winnipeg up in Canada. To the west of those cities? Not much until you reach western California and the Pacific Northwest.
The major reason why the population drastically changes is rainfall. It rains much more on the east side of the line versus the west. The reason for the drastic change in rainfall is that the Rocky Mountains create a colossal wall known as a rain shadow that prevents moisture from passing from the Pacific Ocean. This has created a large swath of dry land that’s not conducive to larger populations.