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Superhero Ice Scientists Lonnie Thompson’s Article in the Behavior Analyst:The Snows of Kilimanjaro

By December 26, 2010February 20th, 2013Impacts

The ice fields atop Mount Kilimanjaro have lost 85 percent of their coverage since 1912;

The Quelccaya ice cap in southern Peru — the largest tropical ice field on Earth, has retreated 25 percent since 1978;

Ice fields in the Himalayas that have long shown traces of the radioactive bomb tests in the 1950s and 1960s have since lost that signal as surface melting has removed the upper layers and thereby reduced the thickness of these glaciers;

All of the glaciers in Alaska’s vast Brooks Range are retreating, as are 98 percent of those in southeastern Alaska. And 99 percent of glaciers in the Alps, 100 percent of those in Peru and 92 percent in the Andes of Chile are likewise retreating;

The ice fields that top Mount Kilimanjaro, Africa’s highest peak, could disappear within 25 years because of rising global temperatures, scientists say. Read more:

In 2000, Thompson and his colleagues found a layer of ice 1.6 metres below the surface of Kilimanjaro’s Northern Ice Field with a radioactive marker corresponding to the Operation Ivy nuclear weapons tests in the Marshall Islands in 1952. The marker has been found in glaciers around the world. That layer is now gone at Kilimanjaro, the ice field having lost 2.5 metres of thickness between 2000 and 2007. ‘Lost half of its thickness’ The tops of both the Northern and Southern Ice Fields have thinned, by 1.8 metres and 5.1 metres, respectively. A smaller glacier, called Furtwangler, has thinning about 50 per cent between 2000 and 2009. Read more:

They found elongated air bubbles trapped in the ice at the top of one of the glacier cores, suggesting the surface ice melted and refroze. They found no other evidence of such melting in the column of ice drilled out of the glacier. A 300-year drought about 4,200 years ago left a two-centimetre layer of dust in the core, but no evidence of sustained melting. Read more:

Between measurements in 1976 and 2000, the area of Furtwängler Glacier was cut almost in half, from 113,000 m² to 60,000 m². During fieldwork conducted early in 2006, scientists discovered a large hole near the center of the glacier. This hole, extending through the 6 meter (20 ft) remaining thickness of the glacier to the underlying rock, is expected to grow and split the glacier in two by 2007. The 2006 study found that no new glacial ice has accumulated on any of the glaciers on the mountain in the 21st century.

Behavior Analysts Climate Special Fall 2010

Thompson, et. al., Kilimanjaro ice core records – evidence of holocene change in tropical africa, Science, October 2002