We’ve been studying a glacier in Peru for 14 years – and it may reach the point of no return in the next 30

High mountain environments in South America, which in many locations encompass peaks that reach 21,000 feet (6,500 meters) or more in altitude, are home to some of the most spectacular glaciers on our planet. My research on one particular glacier shows how endangered these environments are.

In recent years my colleagues and I have been studying the fate of one site in the high Andes of Peru. We work in a location in southern Peru which hosts what used to be the world’s largest tropical ice cap, called Quelccaya. This ice cap covers an area the size of more than 9,000 football fields draping an entire high-elevation plateau in thick ice.

Quelccaya ice cap in Peru. Doug Hardy, CC BY-SA
To better understand how climate change affects this site, my colleague Doug Hardy from the University of Massachusetts and myself installed an automated weather station on the summit at 19,000 feet (5,680 meters) in 2004.

Our climate analysis, together with remote sensing data analyzed by my former Peruvian Ph.D. student Christian Yarleque, clearly documents that the ice cap has been shrinking rapidly in recent decades. And in a recent study, we were able to show that we will lose this ice cap soon unless we dramatically reduce our global greenhouse gas emissions in the next 30 years.

Unfortunately Quelccaya is not a unique case, as climate change is rapidly transforming the high-mountain environments in the Andes from Venezuela in the north to Chile in the south. As our work in Peru shows, these changes will have profound effects locally, with potential repercussions far from the glacier sites.

Two photos taken from the same location 15 years apart shows the extent of glacier retreat on world’s largest tropical ice cap at Quelccaya, Peru. Doug Hardy, CC BY-SA

Many demands on glacier water

As a climate scientist who specializes in understanding the influence of climate change on Andean glaciers, I have been witnessing this process for almost three decades, since I first starting working in the Andes in the early 1990s. Glaciers in many ways are ideal to study climate change because they allow people to visualize the changes in our environment. Changes in glacier extent, which can be seen in many locations around the world, can be interpreted as a direct response to changes in climate.

An automated weather station on the summit of Quelccaya ice cap. Mathias Vuille, CC BY-SA
But these glaciers are not only of scientific interest to people like me, as they provide the fundamental basis for the livelihoods of people who live near these mountains. Glaciers essentially operate like giant water reservoirs and continually release water through melt. People living downstream use this for drinking water and sanitation, to irrigate their fields and to maintain large wetlands and pastures where their llamas and alpacas can graze.

The same water is also being used by hydropower companies to produce electricity, for mining purposes and for large-scale irrigation projects where crops are grown for export. Hence, there are many competing interests that rely on this glacier melt water and the pressure on this water resource is further exacerbated by a rapidly growing demand due to population growth and expanding economies. Indeed, in some locations in the Andes conflicts over water allocation and who controls, regulates and determines access to water have been simmering for quite some time, highlighting the need for adequate water governance.