“Weather in this town is very changeable.” These words from a Chinese student were meant as a consolation as we were slogging through chilly wind that was driving rain into our faces last week.
Conditions in Hefei, located in Anhui Province of eastern China, should be comparable to Atlanta. But they change more quickly.
Both cities have a population, suburbs included, in excess of 5 million. They are at similar latitude, with Hefei being 2 degrees (about 130 miles) farther south. Atlanta is located 34 degrees north of the equator. Both cities are near the southeastern edge of a large continent, which should bring warmth from the subtropical ocean waters nearby.
In Hefei, 85 degree days in early May alternated with heavy rain and daytime highs around 60. Atlanta had some rainy days, too, but the rain was warmer.
A close look at Google Earth helps explain why there was a strong, cold wind from the north a few days ago as I was heading to the airport. The weather map showed high pressure 1,000 miles to the northwest, near the border with Mongolia.
The air coming out of that high pressure followed the textbook rule, flowing clockwise. As it mixed with moisture from the Shanghai region, just 300 miles farther east, cold rain was the result. Those of us traveling in cars and buses felt privileged.
Outside, people on the many motor scooters that are popular in Asia were trying to use rain ponchos, tarps, blankets and even umbrellas to shield against the wet onslaught.
Atlanta, too, is at a distance of 300 miles west of an ocean shore. The distance to the Rocky Mountains is about 1,000 miles, similar to Hefei and the large mountain ranges to the northwest of that city. But we don’t have an enormous rock plateau to the west the way China does.
The Tibetan Plateau occupies a large part of Asia like a gigantic road block. Wind from Mongolia is funneled neatly around the eastern edge of the plateau, and into the highly populated areas of eastern China.
Georgia lacks this effect, because the Ozarks to our west don’t compare in size to Tibet. Strong cold fronts from Canada are becoming more rare now in the second half of spring season, so the weather in the Atlanta area is less bouncy than I observed it in the equivalent region of eastern China.
Rudi Kiefer, Ph.D., is a professor of physical science and director of sustainability at Brenau University. His column appears Sundays and at gainesvilletimes.com.