A green city promotes economic development by providing an environmental friendly framework that encourages new trends that will provide monetary and social investment into the city, which creates a healthy and sustainable community. Environmental conservation and economic development are not conflicting but can be mutually reinforcing, as environmentalists have prompted calls for "environmentally sustainable" economic development. Economic development can be made progressive by reducing some of the detrimental effects of global warming, which for the most part, are man-made. By improvising on behaviors and understanding the need for a more environmentally friendly atmosphere, economic development can go green. Environmental sustainability can best spur regional development and economic growth by creating green jobs through retrofitting buildings in using renewable energy, cleaning-up and reinvesting in brownfield sites to create green space for mix-used communities, and to strengthen the public transportation infrastructure to bring commerce activity.