Environmental Reasons for Migrating

People are pulled toward physically attractive regions and pushed from hazardous ones. In this age of improved communications and transportation systems, people can live in environmentally attractive areas that are relatively remote and still not feel too isolated from employment, shopping, and entertainment opportunities. At the same time, environmental factors result in the forced migration of some people, especially those who are socially and economically disadvantaged.

Push Factor: Katrina Flooding

Migrants are sometimes pushed from their homes by adverse physical conditions. Water—either too much or too little—poses the most common environmental threat.

Many people are forced to move by water-related disasters because they live in a vulnerable area, such as a floodplain. A floodplain is the area subject to flooding during a specific number of years, based on historical trends. People living in the “100-year floodplain,” for example, can expect flooding on average once every century. Many people are unaware that they live in a floodplain, and even people who do know often choose to live there anyway.

Rising waters during hurricanes can force people to migrate. Large-scale forced migration has occurred in recent years in the United States because of hurricanes Katrina, Harvey, and Maria.

Hurricane Katrina hit New Orleans and neighboring communities in August 2005. It killed 1,836 people and temporarily displaced more than 1 million people, including between 80 and 90 percent of the residents of New Orleans.

Migration From New Orleans After Hurricane Katrina

1. How do the concepts of relocation diffusion and distance decay discussed in Chapter 1 help to explain the distribution of people displaced from New Orleans by Katrina?

2. What might account for the large number of migrants who went to Houston?

New Orleans was especially vulnerable because the site of the city is below sea level. To protect it and other low-lying cities from flooding, government agencies had constructed a complex system of levees, dikes, seawalls, canals, and pumps. Two days after the hurricane hit, the flood-protection levees in New Orleans broke, flooding 80 percent of the city

Impact On New Orleans of Hurricane Katrina

(a) Extent of flooding, (b) distribution of African Americans, (c) population change after Katrina.

African Americans lived in rental housing in the lowest-lying areas, most vulnerable to flooding. The wealthy portions of New Orleans, such as tourist attractions like the Vieux Carré (French Quarter), were spared the worst because they were located on slightly higher ground.

In the immediate aftermath of Hurricane Katrina, the population of New Orleans declined by 53 percent, from 484,674 in 2000 to 230,172 in 2006, according to the U.S. Census Bureau. Although some eventually returned, the population of New Orleans remains lower than before the hurricane; the city’s population of 382,922 in 2016 is 21 percent lower than in 2000.

Most of New Orleans’ residents who emigrated in the aftermath of Katrina were African Americans. The number of African Americans living in New Orleans declined from 325,947 in 2000 to 229,143 in 2016, and the city's percentage of African Americans declined from 67 percent in 2000 to 60 percent in 2016.

Push Factor: Harvey & Maria

The largest number of African Americans who left New Orleans after Katrina moved to Houston. Many of these recent arrivals to Houston faced another devastating hurricane, this time Hurricane Harvey in August 2017. Eighty-eight people died, 12,700 homes were destroyed, and 203,000 homes were damaged. During the hurricane, 39,000 were forced to evacuate.

A month after Harvey, Hurricane Maria caused massive damage to several Caribbean islands, including Puerto Rico, where several thousand people died and even more were forced to migrate. Hampering rescue and rebuilding operations was the lack of electricity in much of the island for an extended period of time. The lack of accurate information concerning the number of fatalities and forced migrations in Puerto Rico, as well as the extent of damage, led relief organizations to seek assistance from scientists, including geographers, as described in Doing Geography in Chapter 1.

Emigration From Puerto Rico After Hurricane Maria

Pause & Reflect 3.3.2

Compare Harvey's effects on Houston with Maria's effects on Puerto Rico. Why did so many Puerto Ricans feel compelled to migrate?

Pull Factor: Attractive Environments

Attractive environments for migrants include mountains, seasides, and warm climates. Proximity to the Rocky Mountains lures Americans to the state of Colorado, and the Alps pull French people to eastern France. The highlands of Scotland are attracting migrants from southern areas of the United Kingdom.

Regions with warm winters, such as southern Spain and the southwestern United States, attract migrants from harsher climates. The southern coast of England, the Mediterranean coast of France, and the coasts of Florida attract migrants, especially retirees, who enjoy swimming and lying on the beach. Of all elderly people who migrate from one U.S. state to another, one-third select Florida as their destination.

Many of the world’s islands are in danger due to rising ocean levels. Sea levels rose around 17 centimeters (6.7 inches) during the twentieth century. Scientists working for the United Nations forecast a greater rise during the twenty-first century.

The country of Kiribati, a collection of 33 small islands, in the Pacific Ocean, has already witnessed the disappearance of two of its islands under rising sea levels (Figure 3-37). Anticipating that the remaining islands will be submerged by 2050, Kiribati purchased 2,500 hectares (6,000 acres) of land in Fiji in 2014, as a place to relocate all the country’s 120,000 inhabitants. Kiribati President Anote Tong called the project “migration with dignity.”

Flooding In Kiribati

President Tong’s successor Taneti Maamau has not implemented the migration program. He argues that improving the standard of living can generate resources for the impoverished country to adapt to rising seas, such as by constructing strong seawalls.

Kiribati and other Pacific islands are atolls—that is, islands made of coral reefs. A coral is a small sedentary marine animal that has a skeleton made of calcium carbonate. Corals form colonies, and the skeletons build up to form coral reefs. The threat of climate change to the sustainability of coral is especially severe: Coral stays alive in only a narrow range of ocean temperatures, between 23°C and 25°C (between 73°F and 77°F), so global warming threatens the ecology even if portions of the islands remain above sea level.

Humans are attracted to coral for its beauty and the diversity of species it supports. President Maamau is hopeful that tourists can be attracted to view the country’s outstanding coral. But coral is very fragile, and human-caused water pollution and physical damage—as well as warming temperatures—can kill it.

1. Describe two ways in which climate change affects coral atolls.

2. Is there an alternative to migration for the inhabitants of low-lying Pacific islands? Explain.