UNESCO recently published a report which addresses the effects of global warming on the glaciers of the Andes. The Andean Glacier and Water Atlas examines the changing climate patterns across western South America, as well the historical and projected rates of retreat of important glaciers in the region. Increased melting will impact societies reliant on glaciers for water resources. The eventual loss of glaciers presents a challenge for countries to address.
The Andes are the longest continental mountain range in the world, spanning the western edge of South America through several countries. These mountains are considered to be the water towers for the surrounding populations. They provide water to about 75 million people living within the Andes region and 20 million downstream along surrounding rivers. The Andes continue to have a significant influence on local cultures and economies. The impending loss of these glaciers may cripple dependent communities, industries, and various sectors across South America.
Key Messages and Future Projections
The atlas identifies several key messages essential for discerning the changes in the Andes. Projections indicate that temperatures in the tropical Andes could increase between 2°C and 5°C by the end of the 21st century. The recent IPCC SR1.5 report emphasized the devastating effects of just 1°C of warming, such as extended periods of drought and extreme global heat events. The Andes will likely experience increasingly hotter years with warming driving further glacier retreat.
The report notes that changes in precipitation are harder to project than temperature changes. Nonetheless it presents serious concerns for some regions across the Andes. The atlas refers to the IPCC for precipitation projections. In the southern Andes region, precipitation will greatly decrease by the end of the century, including Chile and Argentina in particular. These regions will likely experience drought events, and loss of glaciers may be devastating to the environment and its people.
Scientists have also observed rapid retreat in glaciers in the tropical Andes, as well as lower-altitude glaciers. According to the atlas, one glacier which remains in Venezuela will likely disappear by 2021. Many large tropical glaciers exist in Peru, including Quelccaya Ice Cap, which may disappear by 2050 at the current rate of warming. Glaciers are also quickly retreating in Bolivia, Chile, and Argentina. This retreat and volume loss of glaciers is “locked in,”and glaciers will continue to retreat no matter what. Even with a moderate level of emissions, the IPCC projects that barely a fifth of the glaciers will remain by the end of the century, with some reduced to barely 3 percent of their current size.
Impacts of Retreating Glaciers
The loss of glaciers and glacial meltwater is inevitable. As warming continues, a majority of glaciers will soon experience “peak water” (which occurs when melting exceeds new mass accumulated by snowfall), likely within the next 20 years. Many tropical Andes glaciers already reached peak water in the 1980s and have been outputting less water since. Although many countries will benefit from peak water, the aftereffects of less meltwater outflow will heavily strain the available water supply.
Bolívar Cáceres, a specialist of the tropical Andes who worked on the atlas, told GlacierHub about some of the effects of glacier retreat and possible methods for adapting to water scarcity. “One of the indirect effects of long-term melting in communities is the reduction of visitors. Since glaciers no longer exist in some places or become very difficult to climb, tourists are currently opting out and most likely will go to other places in the future,” he said. This will affect local economies that depend on tourism flow and the resources generated. As for adaptation, Cáceres believes that promoting technologies in agriculture and livestock areas to better manage water resources is essential for sustainability.
Water quality will also be affected by the loss of glaciers. Bryan Mark, an expert on Andes and Peruvian glaciers, added: “Recently glacier-free landscapes feature lots of unconsolidated materials that tend to result in more sediment laden, erosive, and ‘flashy’ discharge streams.'” Sediment pollution presents a number of problems for the water supply, including degrading the quality of drinking water for locals and their livestock. Mark also highlighted the importance of diversifying water reservoir resources, utilizing groundwater, small dams, and precipitation capture as alternate water resources.
Efficacy and Practicality of Policy Recommendations
The atlas examines the significance of glacier retreat on communities. It provides policy recommendations for countries to sustainably secure future water availability. Some examples include implementing preventative measures for natural glacier-related hazards and developing climate services for water resource management. Although these recommendations are intended to provide direction towards sustainable water supply management, there are concerns of clarity, implementation, and effectiveness of these policies.
Dirk Hoffmann, an expert on glaciers in high mountain ecosystems, commented on the effectiveness of the policy recommendations on communities. “The policy recommendations are all very interesting, but on the whole seem to be somewhat too general as to be useful to specific decision maker,” he said. Hoffmann views the recommendations as well intended and believes the atlas to be effective in raising awareness of these issues. In a practical sense, however, they are too far removed to help decision makers, he said. A clear indication as to whom these recommendations are directed towards would be beneficial.
Mark Carey, an expert of the Peruvian Andes, shared similar thoughts on the effectiveness of these recommendations. Carey stated that the lack of social science and humanities research on vulnerability and unequal impacts of shrinking glaciers is an issue. “Vulnerability is framed in ways to conceptualize homogenous ‘affected populations,’ such as those in agriculture or urban areas, rather than understanding the complicated social divisions and power imbalances embedded in the diverse social groups,” he said. Carey added that although the science is necessary, the complex human dimensions of climate change adaptation are essential.
The Andean Glacier and Water Atlas recognizes the importance of improving interactions between science and policy, bringing awareness of key issues surrounding the loss of glaciers in the Andes. This is a major step towards successful adaptation; climate scientists, social scientists, and policymakers will need to collaborate to effectively allocate resources for sustainable management of the challenges associated with glacier retreat.