I’m back in Texas now, but exactly one full moon ago I stood on top of Africa. As I continued my slow march to the summit I watched the circular white disk of August 2016’s full moon slip behind the frozen blue-brown crags of a declining, yet still powerfully majestic, glacier near Kilimanjaro’s Uhuru Peak. That sight, along with the sun bursting above the clouds to the east at the same time, was without compare.
In 1938 when Earnest Hemingway wrote The Snows of Kilimanjaro there was much more snow and a much larger glacier compared to now. But, even in the 1930s the glacier was shrinking and it was due to the natural cycles of climatic change.
“THE SQUARE TOP OF KILIMANJARO”“WIDE AS ALL THE WORLD, GREAT, HIGH, AND UNBELIEVABLY WHITE IN THE SUN…”EARNEST HEMINGWAY, THE SNOWS OF KILIMANJARo
In the late 1880's the entire top of this volcanic mountain was covered by ice–almost eight square miles of it. By 1912 the overall coverage was down to less than four and a half square miles. Since the first core samples were taken (in October of 1912) it is estimated that 85% of the glacier has disappeared. Today, only about one-half square mile of Kili’s top is covered by ice.
Some estimates say that soon there will be no glaciers left on Kilimanjaro. “If current climatic conditions persist, the legendary glaciers icing the peaks of Africa’s highest summit for nearly 12,000 years, could be gone entirely by 2020.”1 I was just there; I can’t imagine how it could all be gone in just four years. I’d perfer to go with other–yet still dire–predictions that say that it will be 2030, 2040, or even not until 2060 before all the white disappears.
This is the hard-to-imagine, but seemingly unstoppable, reality. It is THE BAD NEWS and some of it CAN be blamed on “global warming.” After all, Kilimanjaro lies about 220 miles–or three degrees–south of the equator; of course the ice fields in the tropics are susceptible to global warming. But, for those of us who feel some guilt about what’s happening to our planet, there are other factors at work that, when taken into account, can perhaps lessen our burden a bit.
First of all, the snows of Kilimanjaro have been melting for many, many decades (long before “global warming” became a thing) because the surface temperature of the Indian Ocean and atmospheric circulation and precipitation patterns have been “starving the ice” since the late 19th century. [2]
Another major factor is the human-caused “forest reduction” on the lower slopes of the mountain. People need to eat and Tanzanians have been clearing the trees for centuries in order to grow crops on the most futile soil that the country offers. But, it is this “loss of foliage” that “causes less moisture to be pumped into the atmosphere, [and] lead[s] to reduced cloud cover and precipitation and increased solar radiation and glacial evaporation.”[1]
The glacier has actually been “doomed” for a long time because the “high vertical edges of the remaining ice make a horizontal expansion of the ice cap more difficult.” (As you can see in the full moon picture above, the glaciers look like cliffs, not the huge, flowing masses of blue ice like you see in Alaska, for example.)
One report explained that even though “there is not a highly significant change in air temperatures” on top of this volcanic mountain–it is always below freezing–even in years with significant snowfall, it is the intense solar radiation on all that dark lava rock and dust that causes the melting of the vertical face of the glaciers. These summit-type glaciers have no where to go once their vertical margins are exposed . They shrink, break apart, and shrink even faster as more and more surface area is exposed to the sun’s infrared rays.[3]
Finally, because the ice cliffs can’t catch and retain new snow the surface of the vertical cliffs are brown and dirty because they are made of old (really old!) layers of dirty snow and ice. “A darker glacial surface absorbs more solar radiation than fresh, white snow.”[1]
BUT HERE IS SOME (potentially) GOOD NEWS?
A 2007 American Scientist article entitled The Shrinking Glaciers of Kilimanjaro: Can Global Warming Be Blamed? offers a potentially positive scenario in which Kilimanjaro’s beautiful white top could regrow and reform. If, due to global warming, the temperatures rise above freezing from time to time the heating of the ice surface would “gradually erode the sharp corners of the ice cap” and create a gentler slope. If “precipitation increased, snow could [then] accumulate on the slopes and permit the ice cap to grow.” Also, more snowfall “could blanket the dark ash surface so thickly that the snow would not sublimate [or turn into vapor] entirely before the next wet season. Once initiated, such a change could allow the ice sheet to grow.” Glaciologists know that the ice cap may indeed vanish, or it may actually grow again…It is ironic that perhaps, substantial global warming accompanied by an increase in precipitation might be one way to save Kilimanjaro’s ice.” [4]
Meanwhile, take solace. Why we can’t count on having a white-capped Kilimanjaro in our future it does seem, for now anyway, we are safe in the knowledge that each month the moon will continue to show it’s full face to us again and again. At least we will always have that to marvel upon.
Full Moon Setting over Texas Hill Country, September 2016
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