by Zoraida Portillo
[LIMA] Climate change-induced glacier melts have cost northern Peru's mountains 26 per cent of their surface area in the last 33 years, satellite images have confirmed.
The reduction is equivalent to 188 square kilometres of the Cordillera Blanca, the highest tropical mountain chain in the world. The mountain range is home to more than seven hundreds glaciers, with the glacier Huascaran declared a world heritage site by UNESCO.
Marcos Zapata, head of the glaciology unit at the National Institute of Natural Resources (INRENA), says that the glaciers are melting by around 20 metres per year — compared to a rate of nine metres per year recorded until 1977.
Zapata was a speaker at the Cycle of Conferences on Glaciological Research in Peru, organised by INRENA in Lima earlier this month (18 July).
"At present, there are more melting glaciers and therefore there is a relative increase in flows in rivers and streams", Nelson SantillÃ¡n, a researcher at the INRENA glaciology unit, told SciDev.Net.
SantillÃ¡n says that, while this currently does not have any significant negative effects, people must be warned about the correlation of this with the increased glacier melting and the future halt in water flow. INRENA estimates this could be as soon as 2020.
This could have severe consequences since the population and number of agricultural areas near the glaciers is growing at higher rates than three or four decades ago, SantillÃ¡n says.
Andean scientists have suggested the Paramos ecosystem in the northern Andes as an alternative source of water for communities when the glaciers disappear. The ecosystem retains and absorbs water in wetland areas.
"The Paramos can act like a big sponge to contain [excess water from] the melting of the glaciers," says Jorge Recharte, director of the Andes programme at the Mountain Institute in Peru. "If they are conveniently managed they could provide an alternative [source of water]."
A 2002 study by Recharte indicated that the Paramos is a source of drinking water for thirteen million Peruvians who live on the coast.
"Given the difficulty of controlling glacier melting, it is definitely important to work in the conservation of grasslands and high forests located in the upper basins of the Andes to keep some water availability in the coming years," Recharte wrote.