The people of South America are heavily dependent on the continent�s natural resources—from the rangelands at the foothills of the Andes, to the plants and animals of the Amazon rainforest, to the fisheries off the coast of Peru. The region�s ecosystems are particularly vulnerable to the changes in water availability expected with a changing climate. Higher global temperatures along with more frequent El Ni�os may bring increased drought, and melting glaciers in the Andes threaten the future water supply of mountain communities. Signs of a warming climate have already appeared both at high elevations—in glacial retreat and shifting ranges of disease-carrying mosquitoes—and along the coast—in rising sea level and coral bleaching.
Fingerprints
45. Recife, Brazil -- Sea-level rise. Shoreline receded more than 6 feet (1.8 m) per year from 1915 to 1950 and more than 8 feet (2.4 m) per year from 1985 to 1995. The dramatic land loss was due to a combination of sea-level rise and loss of sediment supply following dam construction, harbor dredging, and other coastal engineering projects.
64. Andes Mountains, Peru -- Glacial retreat accelerates seven-fold. The edge of the Qori Kalis glacier was retreating 13 feet (4.0 m) annually between 1963 and 1978. By 1995, the rate had stepped up to 99 feet (30.1 m) per year.
92. Chiclayo, Peru - Large increase in average minimum temperatures. Average minimum temperatures along Peru�s north coast increased 3.5�F (2�C) from the 1960s to 2000. The temperature in the high plateau region in extreme southeastern Peru has also risen 3.5�F (2�C), from an average of 48�F (9�C) in the 1960s to 52�F (11�C) in 2001. Northwestern South America has warmed by 0.8-1.4�F (0.5-0.8 �C) in the last decade of the 20th century.
101. Tropical Andes (Ecuador, Peru, Bolivia, and northernmost Chile) - Increase in average annual temperature. Average annual temperature has increased by about 0.18�F (0.1�C) per decade since 1939. The rate of warming has doubled in the last 40 years, and more than tripled in the last 25 years, to about 0.6�F (0.33�C) per decade.
128. Argentina - Receding glaciers. Glaciers in Patagonia have receded by an average of almost a mile (1.5 km) over the last 13 years. There has been an increase in maximum, minimum, and average daily temperatures of more than 1.8�F (1�C) over the past century in southern Patagonia, east of the Andes.
132. Venezuela - Disappearing glaciers. Of six glaciers in the Venezuelan Andes in 1972, only 2 remain, and scientists predict that these will be gone within the next 10 years. Glaciers in the mountains of Colombia, Ecuador, and Peru show similar rapid rates of retreat. Temperature records in other regions of the Andes show a significant warming of about 0.6� F (0.33�C) per decade since the mid-1970s.
Harbingers
15. Andes Mountains, Columbia -- Disease-carrying mosquitoes spreading. Aedes aegypti mosquitoes that can carry dengue and yellow fever viruses were previously limited to 3,300 feet (1,006 m) but recently appeared at 7,200 feet (2,195 m).
36. Monteverde Cloud Forest, Costa Rica -- Disappearing frogs and toads. A reduction in dry-seson mists due to warmer Pacific ocean temperatures has beenlinked to disappearances of 20 species of frogs and toads, upward shifts in the ranges of mountain birds, and declines in lizard populations.
47. Pacific Ocean, Panama -- Coral reef bleaching.
53. Caribbean -- Coral reeef bleaching.
58. Galapagos -- Coral reef bleaching..
86. Nicaragua -- 2.2 million acres (890,308 hectares) burned, 1998. Over 15,000 fires burned in 1998, and the blazing acreage included protected lands in the Bosawas Biosphere Reserve.
117. Argentine Islands - Antarctic flowering plants changes. The populations of two native Antarctic flowering plants increased rapidly between 1964 and 1990, coincident with the strong regional warming over the Antarctic Peninsula. The Antarctic pearlwort population increased 5-fold while the Antarctic hairgrass increased 25-fold. The unusually rapid increases are attributed to warmer summer temperatures and/or a longer growing season, which enhance the plant�s ability to reproduce.
125. Galapagos, Ecuador - Coral reef bleaching, March/April 2002. Sea-surface temperatures rose above 81.5�F (27.5�C) several times, causing repeated coral bleaching events. Repeated and prolonged bleaching episodes - expected as tropical water temperatures warm with climate change - eventually kill corals and cause a decline in associated marine species.
143. Pampas region, Argentina/Uruguay - Worst flooding on record, August to October 2001. Nearly 8 million acres (3.2 million hectares) of land in the Pampas region were flooded after 3 months of high rainfall. Mean annual precipiation in the humid Pampa increased by 35% in the last half of the 20th century.
145. Buenos Aires, Argentina - Heaviest rains in 100 years, May 2000. 13.5 inches (34.2 cm) of rain, more than 4 times the average monthly rainfall, fell in just 5 days. Northeastern Argentina is exhibiting a long-term trend of increasing precipitation.
146. Venezuela - Heaviest rainfall in 100 years, December 1999. The heaviest rainfall in 100 years caused massive landslides and flooding that killed approximately 30,000 people. Total December rainfall in Maiquetia, near Caracas, was almost 4 feet (1.2 m), more than 5 times the previous December record. The high death toll was attributed to population growth in vulnerable areas and forest clearing on steep hill slopes.
153. Argentina - Fire outbreak. 3.7 million acres (1.5 million hectares) burned in La Pampa province, sustained by record temperatures and persistent drought. Annual average temperature in Argentina has increased by nearly 1.8�F (1�C) over the last century.
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