Decentralization of the Nation's Main Street: New Coastal-Proximity-Based Portrayals of Population Distribution in the United States, 1950–2000

Abstract

Almost half a century has passed since Jean Gottmann coined the term “Megalopolis” in reference to the almost continuously urbanized stretch of land spanning the East Coast of the United States from southern New Hampshire to northern Virginia. Because a disproportionate concentration of population resided in this Megalopolis, the northeastern core enjoyed an economic and cultural supremacy, and he termed the Megalopolis “The Main Street of the Nation.” By the later 1960s and 1970s, however, population migration patterns began to reflect the influence exerted by the emergence of a second national core centered on the large metropolitan areas along the Pacific Coast, especially those of the Los Angeles and Bay Area conurbations in California. Although of different character, this burgeoning concentration of population, economic activity, and cultural influence may reflect the development of a West Coast Megalopolis that could soon rival the original Megalopolis of the Northeastern Corridor. Today, the U.S. population distribution is largely a bicoastal one. This article documents the emergence of this bicoastal population distribution. Using historical census data and GIS technology, we present a number of novel ways to graphically portray and examine this population redistribution phenomenon. The United States is not unique in witnessing an increasing share of its inhabitants clustering in coastal zones. Current critical policy concerns about the worldwide vulnerability of coastal populations have focused the need for better coastal population estimates and better mapping methods for portraying population redistribution trends.

Exodus from the California Core: Using Demographic Effectiveness and Migration Impact Measures to Examine Population Redistribution Within the Western United States

“…We raised the threshold to 250,000. In addition to size categorization, CBSA units and outside CBSA counties were identified as being either ''east'' or ''west'' according to a geographic ''continental divide'' as in Henrie and Plane (2006). This east/west boundary was derived using a distance-finding algorithm that calculates the distance from the geographic centroid of each county within the contiguous U.S. to the nearest point along the digitized East or West Coast (Fig.…”

Yesterday's Freeway Network of Tomorrow

“…Because of new links and cities added, St. Louis is now the most accessible city on the interstate system. However, the Midwestern focus of accessibility for both networks ignores the reality of an increasingly coastal population (Henrie and Plane ).…”

“…Because of new links and cities added, St. Louis is now the most accessible city on the interstate system. However, the Midwestern focus of accessibility for both networks ignores the reality of an increasingly coastal population (Henrie and Plane 2006). Highway construction has become subject to increasing scrutiny, especially within cities, where the "freeway revolt" was a reaction to massive demolitions of neighborhoods (Schwartz 1976;Mohl 2004).…”

International Comparisons of Population Mobility in Russia

“…While the economies of regions in the "rust-belt" in the northeast were in decline, much of the new economic growth has been found outside these areas causing outmigration to the south and west. More recently, there is some evidence that this trend has slowed down and that the population of the United States is developing a bicoastal distribution, with increasing portions of the population residing within 25 miles of either the east or west coasts and a hollowing out of the middle portions of the country [27]. This is not only the result of long-term structural change in the US economy away from manufacturing towards services but also the increased attraction of amenities as a pull factor in migration decisions.…”