Snows of Kilimanjaro Melting More Rapidly than Believed, Say UMass Amherst Climatologists

AMHERST, Mass. - The glaciers atop Mount Kilimanjaro, the tallest mountain on the African continent, are melting much more rapidly than scientists previously believed, according to University of Massachusetts climatology researchers. More than one meter of surface lowering occurred within the past year, and projections by Ohio State University scientists indicate that if the glacier continues to melt at its current rate, there will be no ice atop the famed Tanzanian mountain within decades.

The UMass findings contributed to results announced by collaborators from Ohio State at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Francisco earlier this week. The UMass climate work has been carried out in collaboration with researchers at Ohio State and is funded by the National Science Foundation.

Measurements by UMass researchers represent the first year-long record of weather data collected at the summit of Mount Kilimanjaro. UMass geoscientist Raymond Bradley led the project. UMass climatologists Douglas Hardy, Mathias Vuille and Carsten Braun were among those who scaled the mountain in February of 2000, to install an automated weather station. When they returned earlier this month, anticipating a net increase in accumulation, they discovered that the ice cap had instead thinned.

“The surface lowered by a meter, and it was solid glacier ice,” said Braun. “A meter of net loss of ice is huge. This is definitely a greater loss in a year’s time than we expected.”

Previous studies have indicated that the mountain has lost 73 percent of the ice area between the first survey in 1912, and a survey conducted in 1989. The new results that were presented at the AAAS meeting by Lonnie Thompson of Ohio State, show that one-third of the 1989 ice area disappeared by the year 2000, demonstrating that by all accounts, the melting is accelerating.

The installation and modification of the Kilimanjaro weather station were conducted in conjunction with ice core research conducted by Ohio State University. The team has conducted similar research at high elevation on mountains in Bolivia. The UMass portion of the project has several objectives:

* to characterize the current climate at the summit Kilimanjaro, and thus help develop a more comprehensive view of climatic conditions at high altitudes in this part of the tropics;

* to help understand the causal mechanisms driving the environmental changes;

* to link the mountain climate to longer-term records at lower elevations;

* to aid in the interpretation of the ice core record.

The Kilimanjaro weather station operates using solar power. It measures and records air temperature, humidity, incoming solar radiation, wind speed and direction, barometric pressure, and changes in the surface height of the ice cap (ice accumulation or melting). Several times a day, the information is sent from Kilimanjaro’s peak to a computer on the UMass campus, via satellite transmitter. The data is managed by the Climate Lab’s Frank Keimig, who automated a system for keeping track of the information. The work is part of a larger UMass geosciences focus on environmental change in the tropics, led by Mark Abbott, Vuille, and Bradley.

Scientists’ concerns go beyond Kilimanjaro itself: “Kilimanjaro is one illustration of a global problem,” said Hardy. “Glaciers have been retreating dramatically, around the world and especially in the tropics.”

The ability to continue research on past climates is a major cause for concern. Scientists hope to retrieve as many ice cores as possible from tropical glaciers in coming years. Chemicals and gases embedded in the ice hold detailed clues regarding past climate variations.

Also, glaciers are important in terms of supplying drinking water and hydropower to nations along the South American Andes, particularly Peru. At Kilimanjaro, there is concern that the melted snowpack would drive away tourism. The UMass team is hoping to launch collaborative research projects at Kilimanjaro National Park in the future, perhaps involving park personnel in climate and environmental monitoring.

“That mountain is the most mystical, magical draw on people’s imagination,” said Hardy. “Once the ice disappears, it’s going to be a very different place.”

Douglas Hardy can be reached at 802/649-1829 or dhardy@geo.umass.edu.