The importance of connections: global interdependence ties our environmental fate to others, but also creates a public store of good examples to follow.

• Author: Shea, Cynthia Pollock

In nature everything is connected to everything else. Aldo Leopold taught us that back in the 1950s. Twenty years after the first issue of World Watch was published, an ever larger segment of the population seems to understand the implications of our interconnectedness.

NASA scientist James Hansen warned us in 1988 that humans were changing the climate and the effects of that change were starting to become evident. Not many people outside of Washington paid attention. Many refused to believe it. Today, millions of people live in town centers to avoid driving to work. Consumers buy the hybrid Toyota Prius in record numbers. Venture capital floods into technologies that reduce energy use or generate power from renewable sources. Architects and engineers brag about who can design the greenest building.

Does this mean our society has figured out how to live in harmony with the Earth's natural systems? Far from it. But we are certainly closer to, if not at, the "tipping point." As Ray Anderson, chairman of Interface and a tireless evangelist for industrial ecology, explains it, An Inconvenient Truth caused the supersaturated solution of concern about climate change to precipitate into action. The movie came after Hurricane Katrina, high gasoline prices, and several reports from the Intergovernmental Panel on Climate Change. An Inconvenient Truth galvanized people around the world to stand up and say "Enough! It's time to get serious about climate change."

My job at the University of North Carolina at Chapel Hill brings me into contact with many people from a variety of backgrounds. In the UNC community, students were the first to understand the profound implications of climate change. They even raised their own fees to invest in renewable energy infrastructure directly on campus. Now some faculty members are changing their research focus--a rare occurrence in academia--to study a range of energy and climate related topics. Our chancellor has signed the American College & University Presidents Climate Commitment, pledging us to climate neutrality by mid-century.

While it's true that talk about climate change still greatly exceeds action, signs of progress abound. When I wrote about renewable energy technologies in the 1980s, California was the only state with commercial wind turbines. Last year, 20 states installed utility-scale wind turbines and Texas surpassed California in the amount of installed generating capacity. Fully half the states now...