What We Know: The Reality, Risks and Response to Climate Change
Climate Change Impacts in the United States: The Third National Climate Assessment
We may be entering the high-stakes endgame on climate change. The pieces—technological and perhaps political—are finally in place for rapid, powerful action to shift us off of fossil fuel. Unfortunately, the players may well decide instead to simply move pawns back and forth for another couple of decades, which would be fatal. Even more unfortunately, the natural world is daily making it more clear that the clock ticks down faster than we feared. The whole game is very nearly in check.
Let us begin in Antarctica, the least-populated continent, and the one most nearly unchanged by humans. In her book about the region, Gabrielle Walker describes very well current activities on the vast ice sheet, from the constant discovery of new undersea life to the ongoing hunt for meteorites, which are relatively easy to track down on the white ice. For anyone who has ever wondered what it’s like to winter at 70 degrees below zero, her account will be telling. She quotes Sarah Krall, who worked in the air control center for the continent, coordinating flights and serving as “the voice of Antarctica.” From her first view of the landscape, Krall says, she was captivated:
I felt like I had no place to put it…. It was so big, so beautiful. I thought it might seem bare, but that b word didn’t occur to me. Antarctica was just too full of itself.
Describing her walk around the rim of Mount Erebus, the most southerly active volcano on the planet, Krall adds: “It’s visceral. This land makes me feel small. Not diminished, but small. I like that.”
In another sense, though, Antarctica is where we really learned how big we are, if not as individuals then as a species. Scientists have long reckoned that we must be filling the atmosphere with carbon dioxide as we burn coal and gas and oil, and indeed the first instrument designed to measure its abundance—erected in the late 1950s on the slopes of Hawaii’s Mauna Loa—found that more CO2 accumulated with each passing year. But that measurement didn’t tell us much about the past. To understand how much danger we were in required knowing how the planet had responded to atmospheric carbon in the distant past. If you take a core sample of an ice sheet, the tiny air bubbles trapped in each layer can give you a good idea of the successive amounts of CO2—and by far the longest ice cores can be collected in the Antarctic.
Walker gives an absorbing account of the difficulties in drilling through glacial ice, retrieving intact cores, and keeping them frozen for study. When the machine freezes up during the process, the European drilling team drops “cognac bombs” of alcohol down the hole to thaw the mechanism. The reward for their exertions is
a perfect, transparent cylinder, about a metre long, cut through with large crystal boundaries that were clearly visible as if through a window. It had never before been seen by human eyes. It was the oldest part of the oldest continuous ice core on Earth. I put my face close to it, careful not to touch, holding my breath.
The team, by the time it finally pulled up its drills, had taken the world’s climate record back about 800,000 years—through many ice ages and interglacial periods. And what it found was simple and unvarying:
Even when our climate was in some other phase, some different way of balancing the many subtle influences that make up the wind and weather and warmth we experience, temperature and greenhouse gases still marched in lockstep. Higher temperature always went with higher CO2. Lower temperature went with lower CO2.
Moreover, in all that long deep history, we’ve never had anywhere near as much CO2 in the atmosphere as we have today. According to Walker, “through the entire [ice core] record, the highest value of CO2 was about 290 parts for every million parts of air. Now we are at nearly 400 and rising.” That is to say, Antarctica, by virtue of being pristine, provides us the best glimpse we’re going to get of the bizarre geological moment we now inhabit.
But of course Antarctica is pristine no longer. Human effects on the atmosphere and climate can actually be read more easily from the South Pole than almost anywhere on earth, and the results are truly horrifying. To put the facts simply, the massive ice sheets are starting to move with awful speed. On the narrow Antarctic Peninsula, which points up toward South America, and where most Antarctic tourists come, melt is proceeding as fast as or faster than anywhere on earth. It’s here that a big chunk of the Larsen B ice shelf broke off in 2002.
But the peninsula contains relatively small amounts of ice; most of the world’s freshwater is tied up in the giant ice sheets of East and West Antarctica. Scientists—innately conservative—had long considered that these giants were comparatively stable, at least over millennia: it’s no easy feat to melt a mile or two of ice, especially when the air temperature rarely if ever rises above freezing. However, as Walker hints toward the end of her account, researchers have grown increasingly concerned about the stability of the West Antarctic in particular.
Enormous glaciers spill out from the West Antarctic ice sheet into the Amundsen Sea in the South Pacific. It’s perhaps the most remote part of the most remote continent, and to make matters worse the most interesting part of it is underwater. So scientists have been sending “autonomous subs” beneath the waves to study the geology, and using satellites to study changes in the height of the ice. Their work wasn’t quite finished when Walker went to press with her book, but her account provides all the background you need to understand what may have been the most depressing announcement yet of the global warming era.
In mid-May of this year, a pair of papers were published in Science and Geophysical Research Letters that made clear that the great glaciers facing the Amundsen Sea were no longer effectively “buttressed.” It turns out that the geology of the region is bowl-shaped: beneath the glaciers the ground slopes downward, meaning that water can and is flooding underneath them. It is eating away at them from below and freeing them from the points where they were pinned to the ground. This water is warmer, because our oceans are steadily warming. This slow-motion collapse, which will occur over many decades, is “unstoppable” at this point, scientists say; it has “passed the point of no return.”
This means that as much as ten feet of sea-level rise is being added to previous predictions. We don’t know how quickly it will come, just that it will.1 And that won’t be all. A few days after the Antarctic announcement, other scientists found that much of Greenland’s ice sheet shows a similar underlying geology, with warm water able to melt it from underneath. Another study that week showed that soot from huge forest fires, which are more frequent as a result of global warming, is helping to melt the Greenland ice sheet, a remarkably vicious cycle.
In certain ways none of this really comes as news. A leading glaciologist, Jason Box of the Geological Survey of Denmark and Greenland (GEUS), has calculated that given the paleoclimatic record, our current atmospheric levels of greenhouse gases are probably enough to produce an eventual sixty-nine feet of sea-level rise.2 But it’s one thing to know that the gun is cocked, and another to see the bullet actually traveling; the news from the Antarctic is a turning point. It doesn’t mean we should give up efforts to slow climate change: if anything, as scientists immediately pointed out, it means we should ramp them up enormously, because we can still affect the rate at which this change happens, and hence the level of chaos it produces. Coping over centuries will be easier than coping over decades.
We also can limit the many other forms of damage beyond the rising sea level (everything from the intensity of droughts to the spread of disease-bearing insects) if we sharply limit carbon emissions now. But the news from the Antarctic does signal, once and for all, that “stopping global warming” is not possible. There is no way to cool the warmer waters that are melting the glaciers. Physics is not going to let us off easily. All our efforts, from now on, must be devoted to keeping things from getting worse than they otherwise will be.
The drama of the discoveries in the Antarctic this May have come as the climax to a year of steadily rising scientific drumbeats, as researchers have tried with increasing insistence to get the message across to the public and policymakers. In March, the American Association for the Advancement of Science issued a blunt manifesto titled “What We Know,” which begins:
The overwhelming evidence of human-caused climate change documents both current impacts with significant costs and extraordinary future risks to society and natural systems.
Climate change, the statement continues, “puts the well-being of people of all nations at risk.”
A few weeks later the White House released its National Climate Assessment, “Climate Change Impacts on the United States,” on a website (Globalchange.gov) that lets you see how your state or region is faring as the temperature warms. The assessment’s innovation is to cast the damage from climate change not as a remote threat but as a current reality:
Climate change, once considered an issue for a distant future, has moved firmly into the present…. Americans are noticing changes all around them.
And of course that’s the case: at the moment, for instance, half the nation is in a state of drought, and California’s is worse than any since at least the 1500s, with widespread wildfires to prove it.
The National Climate Assessment is less important for its content than its implied message: it suggests that the Obama administration is finally going to get serious, at least rhetorically, about climate change. This marks a shift. In the early weeks of President Obama’s first term, administration officials summoned environmental leaders to a meeting where they said they wouldn’t be discussing global warming: in focus groups, it was more popular to talk of “green jobs.” And they kept their misbegotten promise: through the failed talks at the Copenhagen Climate Change Conference in 2009 (the biggest foreign policy fiasco of the Obama years) and the failed congressional attempt at capping carbon the following year, the White House barely muttered the word “climate.”
In the 2012 reelection effort they literally managed to avoid mentioning it (mirroring Mitt Romney), until Hurricane Sandy in the closing days of the contest made that impossible. Campaigning throughout the hottest year in American history, as a drought devastated the center of the country, the Obama team maintained radio silence. And when Obama talked about energy, he went out of his way to make it clear that he was all for carbon, in whatever form it might come. Standing in front of a mountain of oil pipes in Cushing, Oklahoma, for instance, he said:
Under my administration, America is producing more oil today than at any time in the last eight years. That’s important to know. Over the last three years, I’ve directed my administration to open up millions of acres for gas and oil exploration across 23 different states. We’re opening up more than 75 percent of our potential oil resources offshore. We’ve quadrupled the number of operating rigs to a record high. We’ve added enough new oil and gas pipeline to encircle the Earth and then some.
Indeed, by the time President Obama leaves office we will have passed Saudi Arabia and Russia as the largest oil and gas producer on the planet. We’re using less coal in our own power plants, but exporting more. Our actions have resulted in huge profits for oil and gas companies but have not been consonant with the emerging physics. Even when there has been huge public outcry—a record number of public comments, for instance, opposing the Keystone Pipeline—the president has wavered. Indeed, senior officials know how bleak that record has been. The journalist Mark Hertsgaard, writing in Harper’s, quotes a series of Obama confidantes admitting that their actions have been insufficient to meet international targets, much less provide a strong climate legacy.
Still, some changes seem to be taking place. Early in June the president released proposed new regulations on coal-fired power plants, cutting emissions from existing coal-fired plants by up to a third by 2030. They were strong enough to set off a GOP alarm that the president was waging a “war on coal,” and combined with increasing mileage standards for cars, they mean that his administration has done more than any before it to limit carbon emissions. The next day the Chinese responded with at least a vague pledge to cap their own soaring emissions. In the sorry history of our efforts to deal with global warming, it was a red-letter couple of days.
The problem is that doing more than George W. Bush about climate change is not only a low bar, it’s also an irrelevant one. In this case, the useful question is what science demands. Given that during President Obama’s tenure we’ve learned that the Arctic is in galloping melt and that the ocean is acidifying with enormous speed, and given the latest bulletins from the South Pole I have mentioned, we need far more. Defending the recently announced Environmental Protection Agency changes on coal is probably as much as Obama can do with the current Congress, but he will need to leverage such actions with inspired diplomacy to make sure that the “next Copenhagen,” a global negotiating session set for Paris in December 2015, is not a repeat of that debacle.
In order to put pressure on all the negotiators, UN Secretary-General Ban Ki-moon has invited world leaders to New York in September for a climate summit. That gathering will likely feature the usual fine words about future generations, but in view of the twenty-five-year record of diplomatic futility, many of us who have tried to push for action will use the occasion, and the New York backdrop with its fresh memories of Sandy’s inundation, for what may turn out to be the largest street rallies in the history of the climate movement.
The point of the protests will be to open up more space for the leaders to reach further—intensifying the sense of global urgency so that the protests can move the negotiations. There are at least a few signs that such an increasing awareness of the worldwide problem is already in motion. Each round of disasters seems to push the polling data in the direction of action, as would the worrisome prospect of a large-scale El Niño beginning in midsummer, with its likely freight of weather disasters.
The financial community has begun to question the long-term value of fossil fuel stocks. Institutions with large endowments, such as Stanford University, have begun the process of divesting some of their holdings in coal companies; as analysts have pointed out, should the world ever do something about climate change, many of the reserves on which those companies base their worth would have to be left below ground. “This is one of the fastest-moving debates I think I’ve seen in my thirty years in markets,” Kevin Bourne, a managing director of the Financial Times Stock Exchange, told the Financial Times this spring, on the day that Blackrock, the world’s largest asset manager, launched a fossil-free index fund. Clearly, however, it will take a stronger and noisier movement than we’ve seen heretofore—and a global one—to push the players toward actions at all commensurate with the danger.
I began this review with the metaphor of a chess game, but football may be as apt, given the power of the forces we’ve now unleashed. As a civilization, we’re halfway through the fourth quarter and down by three or four touchdowns. Running into the line, even for solid gains, simply can’t win the game. We’ve got to throw some long, unlikely passes.
The good news is that sometimes such daring risks work. The afternoon before the scary news from the Antarctic emerged, a remarkably hopeful statistic came from Germany. There, in the one country that has taken climate change seriously and done the work to change its energy infrastructure, a new record for renewable energy was set. On that afternoon Germany generated 74 percent of its electric needs from renewable sources.
There’s a great deal to be learned about how to store the power of the wind and sun for still and overcast days. We need better grids to make that system of power function smoothly, and they won’t come cheaply. But that a country at a far northern latitude could make a modern economy (and arguably the most successful modern economy) run on power from above, not fossil fuels from below, should give encouragement to us all. It can be done. The resource that got it done in Germany was political will, which is infinitely renewable. If we can get it going.
Ten feet is about the level of storm surge from Hurricane Sandy in New York Harbor. That turned much of lower Manhattan into a temporary Venice; imagine that as the new permanent baseline. ↩
See Chris Mooney, “Humans Have Already Set in Motion 69 Feet of Sea Level Rise,” Mother Jones, January 31, 2013. ↩