A drop of water falls from a melting piece of ice on Argentina's Perito Moreno glacier near the city of El Calafate, in the Patagonian province of Santa Cruz, December 16, 2009. Scientists warn that glaciers in the Andes are melting because of the effects of climate change. According to studies, these accumulations of ice are thawing at a pace so fast that they could disappear in 25 years. [Xinhua/Reuters]