Global warming - problems and solutions

Ecologists have found that excess nitrogen in tropical forests boosts plant growth by an average of 20 percent, countering the belief that such forests would not respond to nitrogen pollution. Faster plant growth means the tropics will take in more carbon dioxide than previously thought, though long-term climate effects are unclear. Over the next century, nitrogen pollution is expected to steadily rise, with the most dramatic increases in rapidly developing tropical regions such as India, South America, Africa and Southeast Asia.