4/2/2014 1:00:36 PM
Arctic Mirages: Confusing Skies and Fantastical Sights
The distances we travel are not far when we're doing fieldwork in northern Alaska. We usually venture between seven and 15 miles by snowmobile across snow and sea ice to reach the polar den sites we study. And we travel at slow speeds because the snow has the consistency of cement and is carved by the wind to resemble frozen waves. Even at our blistering pace of eight to twelve miles per hour, the journey across the all-white landscape is mind-jarringly bumpy to say the least.
During these trips, we frequently encounter strange and disorientating mirages that only appear in very cold climates. This happens when slightly warmer air settles over very cold air near the Earth's surface, causing the skies to produce the most amazing sights.
Real or Not?
The strange thing about these mirages is that they make it hard to tell if landscape features are close or far. All sense of scale is distorted, with faraway objects looming large. They sometimes float above the horizon or drift above upside down! The superior mirage and the fata moranga are two types of mirages seen in the Arctic.
The superior mirage makes objects appear to be floating above their actual position. While the superior mirage is an extraordinary sight, the fata moragana is truly mind-bending. It causes objects or landscape features to be pulled and stretched out high into the sky.
Either can happen during the day or night. The fata morangana is especially dramatic when seen at night, especially if the object being distorted is a ship on the water or a large, artificially lit building. Ships appear to be massive vessels towering over the water and buildings look like towering New York City skyscrapers instead of the low metal structures typically found in the Far North. Small snowdrifts and other topographical features can be distorted into mountains or large glaciers.
Today as we motored across the tundra our trip took us past a few cabins from a fishing camp shuttered for the winter. From several miles away the cabins looked like very large facilities with a number of tall buildings and a wide footprint. As we approached, the buildings and the structures did not appear to get any closer.
Because we had been by the same location many times, our memories told us we should have been passing by the structures to our right. But the buildings remained off in the distance for some time. The disorientation lasted for 20 or 30 minutes and was significant enough for my field partner, Wes, and I to talk about it afterward. Without GPS units mounted on our dash, it would have been hard to tell our speed, position, and where we were heading. The sensation was that we were traveling in circles or possibly not moving at all.
I can only imagine what the early explorers in this region must have felt when experiencing a feta moragana or superior mirage. Without the precise navigational tools that we possess in this modern age, new or unknown landscapes would have been impossible to navigate on a day like today. A few early arctic explorers were fooled into thinking that great mountain ranges or landmasses existed in places where they did not!
Today I felt like one of those explorers.