Reports published in 2003 presented, for the first time, multi-country evidence of the possible impact of global environmental changes such as climate change on the region’s glaciers (Rignot and others 2003, WWF 2003b – see also the Polar and GEO Indicators sections). Reports from at least five countries (Argentina, Bolivia, Chile, Ecuador, and Peru) present accumulating evidence of the retreat of glaciers and ice fields in the tropical Andes and in the extreme southern part of Andean Patagonia (Rignot and others 2003). In Peru, over the past five decades, significant losses have been reported in the Andean glaciers of Yanamarey, Uruashraju and Broggi. In Ecuador, the Antisan glacier retreated eight times more quickly in the 1990s than in earlier decades. The Chacaltaya glacier in Bolivia, known for its ski runs, has lost half its area and two-thirds of its volume since the mid-1990s (WWF 2003b).
In the southern part of the continent, the Andean ice fields in Argentine and Chilean Patagonia – which cover 17 000 km2 and have at least 63 glaciers – retreated twice as rapidly from 1995–2000 as they did in the previous 25 years, losing from four to six per cent of their surface area (Rignot and others 2003). Their meltwater supplies nine per cent of the total water in the world originating from glaciers. This is making a significant contribution to the rise in sea level.
New temperature change studies in the southern Andes conclude that the rise in temperature in the 20th century was the main cause of the retreat of the continental ice fields (Rignot and others 2003, WWF 2003b). This supports the connection between such impacts and climate change and once again highlights regional vulnerabilities to global environmental change.