Some of the Arctic's challenges can be conquered with grit and willpower, but others call for a creative touch. For example, how do you keep heat-sensitive instruments free of frost?
Donatella Zona, an Arctic ecologist at San Diego State University, leads a team studying the flow of carbon year-round in Alaska. In addition to measuring the concentrations of carbon dioxide and methane, she measures the speed and direction of wind that carries those gases between atmosphere and soil, using a device called an anemometer. The type of anemometer she uses works by bouncing sonic pulses between sensors oriented in different directions and detecting how much the wind slows or speeds each pulse's arrival.
If left on its own in an Arctic winter landscape, a standard anemometer will soon become smothered in spiky frost. A company called Ametek sells a version with a built-in heater, but when Zona and her colleagues tried it, they found that the heat itself altered the wind currents they were trying to measure.
The solution came when they realized that they didn't need to keep the instrument hot all the time. Instead, they modified the heating unit to switch on only when needed, discarding the data from the heated periods. This left them with an hour or two of frost-melt time every couple of days, and solid data the rest of the time.
"Our modification allowed us to keep the instruments ice-free during the cold period," said Zona. "It was the thing that allowed us to operate year-round from these multiple sites, and get these datasets that are nearly unique."
Measuring wind in the frozen north could soon become easier for other teams as well, because a company called Campbell Scientific is working to incorporate the advance into a commercial product, said Zona. But despite such advances, she added, the instruments still need tending -- and that takes people willing to brave the cold.