Local actions have global impacts - Urbanization & Global Warming

"Cities are substantive ecosystems in their own right, replete with complex human-environmental interactions and increasing and far-reaching impacts," Grimm and co-authors write.
from the National Science Foundation Press Release on the Effects of Urbanization Extend to the Global Scale

Urban areas have an amazing impact on the environment. On a local scale, we can see how removing forests and laying asphalt and building skyscrapers can change how everything looks. But it also changes the environment itself. The grass and trees are gone. So too are the squirrels, rabbits, insects, and many of the birds. The average temperature changes, because there is no more shade from the trees and no more grass for dew to collect upon. And when it rains, there's no ground to soak it up, it just runs to the nearest drain and disappears from our thoughts. More and more people are living in cities. More land is being converted from natural and agricultural lands to urban purposes (apartment buildings, parking lots, large buildings, factories, etc.)

The world is changing.