The World's Largest Tropical Ice Field is Vanishing

The Quelccaya Ice Cap in the heart of the Peruvian Andres, is the largest tropical body of ice in the world. The ice cap is at an average altitude of 5,470 meters (18,600 ft) and spans an area of 44 square kilometers (17 miles). As the ice cap is retreating, it is exposing almost perfectly preserved plant specimens dating back 5,200 year, indicating that it has been more than 50 centuries since the ice cap was smaller than it is today.


According to recent research, one of the glaciers in this ice cap, the Peruvian Qori Kalis, like the snowfields of Africa's Mount Kilimanjaro, is rapidly melting and could soon vanish completely (comparisons with previous mapping showed 33% of Mount Kilimanjaro's ice had disappeared in the last two decades - 82% since 1912).

The icecap has lost approximately 20% of its area since 1978, and the current rate of retreat is increasing. Ice cores taken from Upper Fremont Glacier in Wyoming show an oxygen isotope profile similar to that of the Quelccaya ice cores at the end of the Little Ice Age, a period of cooler global temperatures between the years 1550 and 1850. The sudden alterations in the oxygen isotope ratio found in ice core samples from these two remotely located glaciers, provide evidence of a sudden global climate change in the mid-latitude regions of the planet.

"I would not be surprised to see half of it disappear in this coming year," said climatologist Lonnie Thompson, from Ohio State University. Thompson has been studying the Qori Kalis glacier since 1978.

"In the first 10 years [that] we observed the glacier, it was retreating 6 meters (19.7 feet) every year," Thompson said. "In the last few years, it has started retreating 60 meters (197 feet) every year - a 10-fold increase. On top of that you will have natural phenomena like El Nino, which release heat into the lower atmosphere," he predicted.

"The combination of those two things will have a big impact on glaciers throughout the tropics," said Thompson. "No matter what we do, we are going to lose the glaciers on Kilimanjaro and the lower elevation glaciers in the Andes."

"Kilimanjaro could be gone by 2020," he suggested. "In the Andes, some of the glaciers are bigger, but I think we are talking 30 to 50 years."

This will cause many problems for some of the poorest people on earth since they depend upon annual glacial melt to sustain their crops. Loss of these glaciers will cause a huge drought and crop failure.

"These changes are going to take place and these people will be impacted," observed Thompson. "They have to find ways to adapt."