Two decades after he first told legislators of the dangers of greenhouse gases and global warming, a key climate scientist repeats his message with even greater urgency.
Director James Hansen of NASA's Goddard Institute of Space Studies made his comments at the National Press Club in Washington as he was honored for sounding the alarm over planetary climate change. VOA's Paul Sisco has the latest installment of our weekly series: Making a Difference.
Ещё видео!