Climate change signals in the Caucasus Mountains
The following is a guest essay from Eric Pallant, professor of environmental science at Allegheny College in Meadville, Pa., and codirector of the NATO Advanced Study Institute on Integrated Water Resources Management. He is reporting from the National Disasters and Water Security conference in Yerevan, Armenia.
October 20, 2007
The last time there was dramatic climate change in Armenia, Noah built an ark, floated for 40 days and nights, and disembarked on Mount Ararat. Armenians insist they have a piece of his old boat in a local museum. Mount Ararat serves as a useful backdrop, snowcapped and picturesque, for the NATO meeting on Natural Disasters and Water Security.
It turns out to be a much more difficult procedure to document climate change in the Caucuses than, say, the Alps. Western Europeans have been sending scientists into their mountains for decades, who then return to their labs with a clear signal that montane temperatures are rising. But after the Soviet Union broke up in the late ’80s, armies replaced Russian scientists in the Caucuses as wars raged in Georgia, Azerbaijan, and Armenia. More than a decade of data was lost — probably the key decade, too, for picking up a signal.
That makes Maria Shahgdanova’s research unique. She has continuous data from two sites in the Caucuses: one on the north side of the mountains in Russia, and another on the south side in Georgia. From the 1930s to the 1970s, when the Alps were getting warmer, there was no change here — but beginning in 1967 temperatures started rising like a low-grade fever.
Between 1985 and 2000, measurements of 113 mountain glaciers showed 107 retreating, five unchanging, and two advancing. On average, they gave up 25 feet per year. Since the end of the 1900s, bare ice has decreased by one-fourth, with 10 percent disappearing in just the last 15 years.
All of that melting ice is accumulating in lakes at the glacial termini. In 1985 there were 16 major lakes. Fifteen years later, there were 22 lakes, and eight of the existing lakes had increased in size. Now comes the scary part: with the fall of the Soviet Union, there has been large-scale deforestation, overgrazing, and unregulated tourism development just below those lakes. When the ice dams burst, as they are prone to do, the consequences are going to be catastrophic.
A second study from Georgia suggests that though floods are not more frequent, their intensity has increased dramatically. Ditto for Afghanistan, where floods used to be relied upon to irrigate fields. Now they come out of the mountains with such force that houses in the floodplain simply wash away. As if Afghans don’t have enough to worry about.
The sense at this meeting is that the former Soviet republics, from Hungary and Romania east to the ‘stans, have a new reason to be paranoid. Most of the scientists here don’t have enough long-term data to confirm that the regional climate is changing; but looking out of their windows, they sense that in some places rainfall is becoming heavier and in others it is getting dryer.
Looking out my conference window, I see that Mount Ararat has disappeared behind a smoky haze of dense air pollution.