Photo taken on August 5, 2012 shows tourists visiting the Perito Moreno glacier, located at 80 km from the El Calafate municipality, province of Santa Cruz, in southeastern Argentina. (Xinhua/Bao Feifei)

Photo taken on August 5, 2012 shows tourists taking pictures of the Perito Moreno glacier, located at 80 km from the El Calafate municipality, province of Santa Cruz, in southeastern Argentina. (Xinhua/Bao Feifei)

Photo taken on August 5, 2012 shows tourists visiting the Perito Moreno glacier, located at 80 km from the El Calafate municipality, province of Santa Cruz, in southeastern Argentina. (Xinhua/Bao Feifei)

Photo taken on August 5, 2012 shows a general view of the Perito Moreno glacier, located at 80 km from the El Calafate municipality, province of Santa Cruz, in southeastern Argentina. (Xinhua/Bao Feifei)