Urban Sprawl

The rate of environmental destruction portends the pace of humanity’s demise. A recent satellite survey discovered global urban expansion in recent decades grew 4 times greater than previously estimated.

From 1985 to 2015, urban land mass grew 80%: from 362,747 km2┬áto 653,354 km2. Each year, 9,687 square kilometers of land – an area larger than New York City – was urbanized.

69% of the newly developed urban areas were in Asia (up 4,970 km2 annually) and North America (+2,358 km2). The US, China, and India are the countries with the most cities.

European urbanization was 1,883 km2/year. Elsewhere in the world (Africa, Australia, South America), urban growth was less than 1,000 km2/year.

Urban expansion occurred mostly nearby a handful of large cities in China and India. Urban encroachment in the US was much more widespread. Las Vegas, Nevada was among the many US cities that mushroomed.

During the same period, urban populations grew by 52%. The differential suggests much of the land grab was for industrial and commercial use, not just housing.

Urbanizing agricultural land predominated in China, India, South Korea, Japan, Europe, Southeast Asian countries, and the central United States. Deforestation provided for urban sprawl in northern Europe and the eastern US. Other land cover types were taken by cities in the western United States and Saudi Arabia.

Reference:

Xiaoping Liu et al, “High-spatiotemporal-resolution mapping of global urban change from 1985 to 2015,” Nature Sustainability (4 May 2020).