Men on horseback, wearing long robes known as "deels," drive herds of livestock—sometimes more than a thousand animals at a time—across the rugged plains, just as their ancestors have done for centuries.
"Mongolians are very dependent on their livestock, and the livestock is very dependent on the environment," said Clyde Goulden, director of the Institute for Mongolian Biodiversity and Ecological Studies at the Academy of Natural Sciences in Philadelphia, Pennsylvania.
Goulden has studied the climate changes occurring in the mountainous area surrounding Lake Hövsgöl Nuur in northern Mongolia.
He confirmed the above-average temperature rise and added that the warming appears to have accelerated over the past ten years.
In a region where winters can be long and brutal, a milder climate would seem to benefit Mongolia's herders. But warmer temperatures stunt the growth of the vegetation that feeds the animals.
"The biggest problem is that [the warming] leads to an increasing loss of soil moisture, which is critical to plant growth," Goulden said.
The average amount of precipitation has remained steady. But rains tend to be more infrequent and heavier when they occur.
"When you have these heavier rains, you get greater runoff, with less of the moisture being soaked up by the soil for the summer growth," Goulden said.
He estimates that 15 to 20 percent of soil moisture is lost due to the changing climate in Mongolia.
Winters have seen the most severe warming, with warmer temperatures ultimately resulting in more destructive ice.
"They'll get a moderate amount of snow, but then there's a warm day and the snow melts, then a cold day again and it freezes," Goulden said.
"This builds up two inches (five centimeters) of ice, and the livestock can't get to the food.
"When that occurs for a month or two, you have a large number of animals dying of starvation," he said.
The changing climate also creates less predictable weather patterns, and it may have an effect on a Mongolian weather phenomenon known as the "dzud," fierce winter blizzards that sometimes cripple the country.
Namdag once owned more than a hundred horses, sheep, cows, and camels. He lost 90 percent of his animals in the devastating dzud of 1999.
"Only the camels survived," he said.
In 2005 there were 81 days of extreme weather in Mongolia, including dust storms, according to Azzaya, the meteorologist.
"Summer temperatures are not changing overall," she said, "but we are seeing an increase in continuously hot days—nine, ten days straight with temperatures over 40 degrees Celsius (104 degrees Fahrenheit), which is something we haven't seen before."
The many novice herders are easy victims to the increasingly severe weather, which tests even old hands like Namdag.
During Mongolia's Communist rule, which lasted until 1990, the government limited the number of livestock in the country to about 15 million.
When Mongolia switched to a market economy and those state-imposed limitations were abolished, many Mongolians with little or no herding experience acquired animals and got into the herding business.
"Many of the people who lost livestock during the dzuds a few years ago were new to herding and didn't understand how to prepare for [extreme weather]," said Goulden, of the Academy of Natural Sciences.
"When disaster struck, they were forced to move to the city."
Keeping the Tradition
There are 33 million livestock in Mongolia today, more than ten times the number of people. But many young people in Mongolia show little interest in the herding lifestyle.
Outside the provincial capital of Mörön, 18-year-old Mendbayr keeps watch on more than a thousand sheep from the back of his Mongolian horse.
His family has been herding for generations, but Mendbayr has other plans for his future.
"I'm going to the university," he said. "I want to become a mechanical engineer like my older brothers."
Others are determined to weather the hardships of the herding life.
An hour's jeep ride north of Mörön, 60-year-old Baasanjav is preparing to dismantle his family's ger to make the winter journey into the mountains, which offer some protection from the biting wind that sweeps across the plains.
"I'm not giving up this life," he said. "It makes me happy to be out here."
One of his two sons, 27-year-old Purevsuren, has agreed to work as a herder.
Baasanjav watched his son stack sacks of cabbage onto a horse-drawn cart for the journey north.
"It's important that our children continue this tradition," he said.
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