The Science of Ice Mar03

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The Science of Ice

John Goodge is a Professor of Geological Sciences at the University of Minnesota-Duluth, and is also one of the New York Times’ Scientists at Work, in which accomplished scientists share notes on their work in the field.


Part of Goodge’s concern – and Pyxis Mag’s, as well, which is why we were so happy that he took the time to speak with us – is climate change, and the effect that the diminishing ice in Antarctica is having on the rest of the planet, as well as on the wildlife that lives in that beautifully desolate, icy, windswept land.

It’s an ongoing challenge to decipher the many mysteries that Antarctica holds, and it’s an even bigger struggle to properly educate the public on what some of those mysteries and climate dangers are. One of Goodge’s main research interests is at the root of the problem – in the tectonic (think earthquakes and volcanos) evolution of the continents. It’s all about how the continental crust (the layers of rock that form the continents) is generated, how it’s deformed, how it’s transformed, and the rates at which these things occur.

“I’m particularly interested in the growth of continents over time, the formation of mountain belts, and the assembly and breakup of supercontinents,” Goodge explains. “One of the most intriguing time periods is at the end of the Precambrian, when multicellular life forms were just beginning to take off at the same time as big changes were taking place in the positions of the continents.”

“And one of the most interesting aspects of this is the formation of the supercontinent Rodinia about 1 billion years ago, which resulted in vast mountain ranges, big changes in seawater chemistry, and the emergence of macroscopic marine organisms.”

Antarctica, Goodge points out, is a key piece in these transformations, because it seems to have been at the center of much of this change. How Antarctica fit with the other existing continents and how they interacted remains a difficult scientific problem.

“The difficulty of studying Antarctica is that only about 2% of the geology of the continent is exposed for direct observation and sampling because it is covered by the major ice caps,” he explains.

And getting to remote field sites in Antarctica is another challenge.

“I typically work out of tent camps in the Transantarctic Mountains, a very long mountain range that transects the continent,” Goodge says. “It is over 2500 kilometers long and up to 14,000 feet high. But this is where the rocks are exposed, so that’s where I work. We fly commercial airline to New Zealand and then military transport to McMurdo Station, the largest base in Antarctica operated by the U.S. From there, after getting supplies organized, we fly to remote sites where we are on our own in small groups – typically 4-6 people – living out of tents and many hundreds of miles from the nearest base.”

The hassle? Totally worth it…

“Antarctica is indeed a beautiful place. Not only for the visual panoramas and the great vistas, but because of the absolute quiet and the pristine air and snow,” Goodge smiles. “Personal challenges obviously include staying warm and out of harm’s way, though – exposure and frostbite are always a concern, especially when the winds blow strong. But most people I’ve worked with have a good sense of how to adjust to the environment and be safe.”

… although that’s not to say it’s the easiest or most welcoming environment to live in for any length of time.

“There are many real dangers in addition to exposure,” Goodge warns. “Some of them are natural like hidden crevasses, and some of them are related to the potential for accidents, and accidents in Antarctica are many times more serious than at home because of the remote setting and cold.”

The odd thing about Antarctica is that it’s actually becoming not quite as cold – and this isn’t a good thing.

“Have I seen evidence of global change in Antarctica? I believe so,” Goodge muses. “Although public and political debate continues, the scientific community is all but unanimous in finding observational evidence for the effects of systematic warming over the course of the last century and a half. These measurements are geographically broad and come from the oceans, atmosphere, ice caps, terrestrial ecosystems, and biological systems.”

“Because of its isolation as a continent in a polar setting, Antarctica both participates in generating change as well as feeling the impact of change,” he continues. “I am not a climate scientist, but my experiences in the deep field over the past 25 years are consistent with the idea of warming trends observed worldwide. Yes, it is still cold in Antarctica and it still snows despite wastage of glaciers at the margins. An irony of climatic warming is that Antarctica may actually see increasing snowfall because greater heating of the oceans forces more moisture into the atmosphere, which leads in turn to more precipitation.”

But in more recent field seasons, the signs that Goodge has seen have been clear and jarring – he’s says he’s seen more meltwater ponds, have flown over streams that course over broad snowfields, and has walked alongside waterfalls and cataracts spilling out of the mountains to the ice below. These, in case you’re wondering, are not sights common to Antarctica.

“These signs of advanced summer melting are occurring at latitudes of 83-85°S and elevations of several thousand feet in the Transantarctic Mountains! These are not scientific observations, but merely personal anecdotes. We should rely on meteorologists, glaciologists and oceanographers to robustly document the changes currently underway, but in the meantime I think it behooves all of us to consider ‘the ice’ as showing signs of change that will have consequences closer to home.”

And we’re now back to the struggle that we mentioned previously in this feature – how to get the public to believe it when they’re fed all manner of conflicting information.

“I think people, and Americans in particular, resist the scientific evidence of climate change because to acknowledge that the climatic changes taking place are to a large degree caused by human activity makes people uncomfortable,” Goodge points out. “They understandably don’t want to think that their lifestyles contribute to global climate change, which is hard to see because the changes are a result of incremental inputs by each individual such that no one person can see the direct result of their activity.

“Also, we are creatures of comfort, and giving up our lifestyle choices, especially in terms of activities that require burning fossil fuels, is difficult.”

The past winter has been one of more comfort for most people – and dismay for scientists who are concerned about the long-term problems, as opposed to the short-term reward of not having to shovel your driveway. But the cool thing (no pun intended) is that Antarctic scientists have devised ways to utilize the ice itself to give them clues about what’s happening.

“The ice core records from Antarctica and Greenland are critical lines of evidence for global climate change,” Goodge explains. “The ice caps in these two areas form by annual accumulation of snow, which eventually compacts and transforms to ice. During snowfall, bits of dust, salt, and air are mixed in with the snow, which are trapped in the recrystallized ice. Paleoclimatology, the study of climate records from the past, in this case uses the chemical composition of the water in the ice, trapped pockets of air, and traces of dust deposited in the ice to reconstruct climatic changes over time. This is possible because the ice records annual layers of snow accumulation. In Antarctica several long ice cores have been taken – the longest of these gives us samples of the atmosphere going back about 750,000 years.”

So what do these records tell us? That’s the damning part.

“First, that the global patterns are clearly of rapid recent change – just the past two centuries – and show that atmospheric conditions have changed more quickly over the recent past than during longer natural cycles (pre-civilization),” Goodge says.

While climate does naturally vary on regular cycles, paleoclimate research is working to understand what causes these oscillations, and it’s being found that overall patterns are similar from Antarctica to Greenland. Goodge’s deciphering of the information they’ve been gathering tells him that we are in for some big changes over the next couple of centuries – and that they’re changes we are already beginning to experience.

“It would be very interesting indeed to time travel to the year 2200 and see how different things look,” Goodge says. “It’s so hard for humans to grasp the changes underway because they take place longer than a human life-cycle, despite a lot of weather fluctuation from year to year.”

A period of ‘continued warming and drying’ around the world is what Goodge envisions – in addition to the unfortunate continuing, and perhaps accelerating, ice loss that’s already begun in Antarctica.

“This is a direct threat to low-lying countries and will at least have big economic consequences for any city near the coast,” he explains. “Agriculture and our water supplies will also be hard hit. Climate models indicate that low and mid-latitude areas will become drier, which is likely to cause big changes in agricultural output as well as adversely affect the replenishment of underground aquifers.”

We were thinking that there might be some more hopeful news.  But in spite of Goodge’s admiration for, work in, and enthusiastic support of the natural world, it’s unfortunately not looking too good at all for this planet we call home. Is the tipping point too far, or is there still something we can do? Only time will tell.

“My greatest fear, particularly in the face of a global population set to reach 9 billion in my lifetime, is for conflict to arise over shortages of freshwater and food,” Goodge concludes, “I am frankly pessimistic about the world that my children will inherit.” - Kristi Kates

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All photos courtesy John Goodge. If you’d like to learn more about climate change, Pyxis Magazine suggests these links:

World Meteorological Organization

WWF Climate Change Action Site

U.S. Environmental Protection Agency

Sierra Club Clean Energy Solutions

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