Outlook on climate change adaptation in the Tropical Andes mountains

Health

as the climate has become warmer. Malaria, dengue fever and other diseases will therefore become more prominent in the mountains. El Niño events and climate change have been demonstrated to significantly increase the altitude at which vector-borne diseases are experienced in Colombia (Poveda et al., 2000). Increased frequency of extreme El Niño events is estimated to contribute to an increase of vector- borne disease (Thomson, 2014). These phenomena in combination could have a significant effect, especially in highly populated areas in the mountains, such as Bogotá andMedellín in Colombia. A recent study from the Antioquia region in Medellín demonstrates that malaria will become more prevalent in the highlands because of increased temperatures (Siraj et al., 2014). The Andes are characterized by significant risk for extreme events. Some are climate driven, such as wildfires, mudslides and avalanches, while others Melting glaciers also contribute to increased risk of Glacial Lake Outburst Floods (GLOFs). As glaciers melt, lakes of meltwater build up and can sometimes burst out, causing severe damage. These lakes are often particularly fragile because the dam is made of loose moraine gravel and rock. Climate change is increasing the risk of GLOFs in the Cordillera Blanca, both because of increased melting and through an increased number of extreme events. In 1970, an earthquake caused the bank of a glacial lake on the HuascaránMountain to collapse, causing a flood that killed 20,000 people (Hegglin and

are not, such as volcanic eruptions and earthquakes. However, climate change will increase vulnerability even to non-climate-driven disasters. For example, the steep slopes of the Andes combined with warming and increasingly concentrated precipitation in some places will increase the risks of landslides. These topographic features exacerbate the problems already expected from increasingly concentrated rainfall and increased frequency of extreme El Niño events. This directly threatens infrastructure, ecosystems and human lives. Socioeconomic issues determine to a significant degree the outcome of such disasters for different social groups. In cities in the Andes, slums are often found along the steepest hillsides and have poor building quality (O’Hare and Rivas, 2005). These areas, home to millions of people, are the most vulnerable to landslides. Due to lack of legal ownership for the residents, as well as lack of infrastructure, these communities have restricted capacity to adapt. Huggel, 2008). In 1941 a similar disaster occurred in the same area after a huge part of a glacier fell into Lake Pallqaqucha, causing a GLOF which killed over 50,000 inhabitants of the city of Huaraz. The Peruvian government has made significant progress in monitoring these lakes and creating risk reducing infrastructure, such as overflow tunnels. These demonstrated their worth in 2002 when a rock avalanche caused a 70 m high wave in Laguna Safuna. Due to the overflow tunnels, no human lives were lost, despite significant damage and the death of a number of grazing animals (Chevallier et al., 2010).

Problems with water supply, hydropower, agriculture and biodiversity all have drastic effects on human health. Agricultural problems will drive poverty and food insecurity primarily among people living in the mountains but also in South America as a whole. Reduced biodiversity and damaged mountain ecosystems will also threaten the nutritional ecosystem services they provide. This includes wild harvesting of edible and medicinal plants and firewood as well as fresh water. Damage to fish stocks and unique Andean ecosystems could also threaten tourism. One broad implication is contribution to poverty and its wide-reaching associated ills. When people’s economic situation is worsened, other negative effects of climate change are aggravated. Changes inwater availability, particularly inpoorurban areas, could cause a significant increase in infectious diseases and generally limit the lives of millions of the most vulnerable. Access to improved sources of water for sanitation in Bolivia was about 61 per cent of the population in urban areas in 2015 (WHO and UNICEF, 2015) , but only 28 per cent in rural areas. In Peru, the numbers are 82 and 53 per cent respectively. Decreased water flow in the dry season will also have significant effects on sewage systems and sanitation. Diarrhoea remains a major killer of children in the world as well as in South America. El Niño events and temperature increases have also been associated with increased frequency of diarrhoea in Peru (Checkley et al., 2000). The relationship between climate change and diarrhoea, however, remains unclear. Warming of the climate also influences the spread of insects and associated diseases (Thomson, 2014). Vector-borne diseases have moved upward in elevation

Glacial Lake Outburst Floods in the Tropical Andes

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