11/12/2013 3:18:41 PM
From Polar Bears to Penguins
We headed out on Tundra Buggy® One around 9:00 a.m. to a chilly -11 °F (-24 °C), following the paths the buggies travel to take ecotourists to see the polar bears. (There is no off-roading, because driving across the landscape would crush the sensitive tundra plants.) Not 10 minutes later we saw our first polar bear, likely a female, wandering toward the lodge. Right after that we saw another polar bear, this one relaxing in a snowdrift. An arctic fox by the side of the buggy path grabbed a frozen bird from its cache and ran off to gnaw on it. We watched and photographed it for a good hour. It was a clear, bright blue morning, with ice crystals floating in the air—a stark contrast to yesterday's bleak, blizzard conditions.
We drove out to Gordon Point, which juts into Hudson Bay. The ice has been rapidly packing into the western Bay—where we are working—these past few days. As I stamped my frozen feet to stave off the pain in my toes, I could not help but meditate on our warming planet. The climate has never been static, of course, and my wife Lisa rightly points out that climatic acceleration is a far better description of what is going on these days. It has gotten warmer many times in Earth's history, but it's happening faster than ever before, we humans are far and away the primary cause of the climatic acceleration, and—of great importance—the consequences will be undesirable for humanity to say the least.
Increased flooding of heavily populated, low-lying places like Bangladesh and Venice; the spread of dengue and other mosquito-borne, tropical diseases to subtropical latitudes; stronger hurricanes and more frequent extreme-weather events in general; and disruption of food supplies as the climatic conditions suitable for agriculture shift out to areas that don't have as much arable land are just a few of the many frightening possibilities that are rapidly becoming more than just vague hypotheticals.
Polar bears, which depend on the arctic sea ice to get out onto the frozen ocean and hunt seals, are in peril as that sea ice takes on average a day longer to form in the fall with each passing year; that's a month shorter hunting season for the bears compared to 30 years ago. Polar bears are not only emblematic of the dangers of climatic acceleration to arctic ecosystems, but their precarious situation is an appropriately brutal metaphor for what we are doing to ourselves.
The impact of diminishing sea ice on polar bears is mirrored in changes to penguin populations in Antarctica, where I do a lot of my research. In parts of the western Antarctic Peninsula, where sea temperatures have been rising at about a degree Centigrade every 50 years—twice the global average—AdÌ©lie penguins are moving south and being replaced by warmer-weather penguins like chinstraps and gentoos. The reasons for these changes are complicated and ecologists have a number of ideas about what's going on, but a large part of the answer is that AdÌ©lies depend heavily on the annual sea ice for their food. Small algae grow on the underside of the sea ice, and krill eat those algae. The AdÌ©lies, in turn, eat the krill. Chinstraps and gentoos have other food sources and do not depend as much on the sea ice. But species of penguins replacing each other is only part of the story, because overall the populations of penguins are tanking.
We traveled back toward the Tundra Buggy® Lodge, where we are staying, and ate lunch in our vehicle. Outside, two young males sparred. This play-fighting is a training exercise for the bears and they establish dominance without bloodshed. They went at it in bouts of stand-up wrestling, rolling around, play-biting, alternating with lying around in the snow and snoozing.
Today was a cold, cold day, and that was a good reminder about the difference between climate and weather. Weather is what happens from day to day, week to week, and season to season. But a cold snap doesn't mean climatic acceleration is a sham, just as a hot spell confirms nothing. Climate and climate change are about long-term averages and trends. How has the average temperature changed over the past few decades? Is rainfall more variable, with more soggy intervals and dried-up times now than there used to be? These are the trends climate scientists are watching, and so far many of their predictions are coming true.
As 3:00 p.m. rolled around, the sun made its way to the horizon and the sky turned orange in the west. We worked on a Tundra Connections webcast to be streamed to K-12 audiences today. After a long nap the two sparring polar bears wandered off. By 5:00 p.m. it was dark. We docked with the lodge and went inside for the night.