Impervious America
The CHL has always been an advocate of paving the planet (for obvious reasons). Now, we have more impervious surfaces in the lower 48 than we have wetlands! Together, we are making great progress. --NF

June 15 (ENN): The combined size of all highways, streets, buildings, parking lots and other solid structures within the lower 48 states and the District of Columbia is some 43,480 square miles, roughly the size of the state of Ohio.

The finding comes from a study by Christopher Elvidge of the National Oceanic and Atmospheric Administration's National Geophysical Data Center in Boulder, Colorado, who along with colleagues from several universities and agencies produced the first national map and inventory of impervious surface areas in the United States. The study appears in the June 15 issue of "Eos," which is published by the American Geophysical Union.

The researchers note the new map is important because impervious surface areas affect the environment. The qualities of impervious materials that make them ideal for construction also reduce heat transfer from Earth's surface to the atmosphere, creating urban heat islands. In addition, the replacement of heavily vegetated areas by impervious surface areas reduces sequestration of carbon, which plants absorb from the atmosphere. Both effects can play a role in climate change. Within watersheds, impervious surface areas alter the shape of stream channels, raise the water temperature, and sweep urban debris and pollutants into aquatic environments. These effects are measurable once 10 percent of a watershed's surface area is covered by impervious surface areas, Elvidge says. An increase in impervious surfaces means fewer fish and fewer species of fish and aquatic insects, as well as a general degradation of wetlands and river valleys.
- nostradamusfunkadelic, 11:19 AM | |