Source: The National Geographic                    Date: 27 July, 2011

A scientific research team led by Mr. Clyde Goulden, an ecologist at the Academy of Natural Sciences of Philadelphia, set up a seasonal research camp in the Dalbay valley in Northern Mongolia valley in 1994, and he has been returning there every year since. At first Mr. Goulden studied the ecology of Lake Hovsgol, a long skinny body of water nicknamed the Blue Pearl, in testimony to its beauty and purity. Lake Hovsgol is 100 miles long and contains about 70% of all of Mongolia’s surface water.

About a decade ago Mr. Goulden noticed that the government meteorological station in Hatgal, the town nearest to his study site, had recorded rapidly rising temperatures. It made him wonder if global warming might be causing mischief at his research site, 70 miles away. Studies by others have since shown that Mongolia has heated up more than almost anywhere else on Earth. Averaged over its entire surface, Earth has gotten about 1.5 degrees Fahrenheit hotter in the last century. Mongolia, in contrast, has grown nearly four degrees hotter since 1960. Many of Mongolia’s lakes and rivers have shrunken or disappeared entirely. Its rangeland has become less lush, a fact one leading Mongolian scientist says is due in equal parts to over grazing by livestock and to soil desiccated by higher temperatures.

Mr. Goulden wanted a detailed, long-term record of how the weather had changed all around the region by Lake Hovsgol. But he could not ask a weatherman which way the wind blows—since the entire region had only one meteorological station with a good long-term record. Fortunately, though, he did not need one. He realized that the herders he had gotten to know casually in years of bumping along the jeep trails here watch the weather vigilantly. He decided to survey them on local weather changes and whether any differences in weather had affected their lives. What he found surprised and disturbed him. When I had arrived at Mr. Goulden’s research camp, he was just completing his third season of surveying herders. One herder and his wife described changes they had seen in the 30 years they have grazed animals in the valley. Summer winds are colder and stronger now than they used to be. When they were younger they could easily anticipate a day’s weather and dress accordingly. Now they cannot.

When they were young the pastures were watered by long gentle rains known in Mongolian as shivree rain. Now showers fall torrentially and only briefly, events called adar rains. They said the adar downpours fall so hard and pass so quickly that the water flows directly into nearby streams and the lake instead of soaking into the soil. A Mongolian wildlife biologist calls adar showers “rains that don’t wet”. The herder said their pasture’s vegetation is stunted, making it harder to fatten their livestock. “If the animals die, what’s the future for us?”

Mr. Goulden has not yet systematically analyzed the approximately 100 herder surveys he has conducted in the last two years. He has not published his results in any scientific journal. But eyeballing his data, he says that what the herder and his wife said tracks closely the responses of the vast majority of his informants. He hopes to confirm what the herders said about changes in rainfall patterns after inspecting rainfall records collected by the Mongolian government. If what the herders say is borne out, and if past trends continue, they will have to invest more time looking for good pastures, and the extra work will make herders’ tough lives tougher.