By Evan Pellegrino
It's time to expect the unexpected. Leading environmental researchers issued that warning on 13 February at the AAAS meeting in Chicago, during a symposium to address how Earth's ecology is responding to climate change. According to the scientists, the debate on why the world is warming has ended. Now that researchers have established that humans are at least partially responsible, they said, it's critical to focus on how climate change might affect life in the 21st century and what can be done to manage the impacts.