Charles Kibaki Muchiri traced the water trickling across the surface of the Lewis Glacier with his fingers, showing how quickly climate change is melting away the huge ice blocks off of Africa's second-highest mountain.

For nearly 25 years, the affable 50-year-old guide has been taking hikers to the peaks of Mount Kenya, nearly 5,000 meters above sea level, and observing their transformation from a landscape of snow and ice to brown rock.

"It was very beautiful," he said mournfully on a recent ascent.

He recalled the ice caves and thick layer of snow that lasted several months on the peaks of this ancient volcano.