About five years ago, I began making daily internet pilgrimages to the Polar Research Group at the University of Illinois’s website – Cryosphere Today. I’d stumbled upon the website after a Google search and found that they provided infrared satellite photos of Arctic and Antarctic sea ice on a daily basis. At the time, somewhat of a human-caused climate change skeptic, but still very interested in the science, I decided that Cryosphere Today would be a fantastic empirical tool to use in discussions with friends, fellow science aficionados, and for developing my personal knowledge-base.
Reading through the site I discovered that since the satellite record had begun in 1979, the Arctic in particular had shown a slow but steady decline in sea ice cover. On the other hand, the Antarctic had remained mostly steady over the period. Overall, world oceans displayed a mild drop in sea ice coverage since the satellite record began. Seeing this, I thought it was a pretty clear indication that the earth was warming, as latent heat in the world’s oceans would have a melting effect on sea ice around the globe. So I kept visiting. But I kept the site under my hat for a time, not yet using it for discussions with friends and wanting to see what would happen over the next few years. Would ice coverage begin to bounce back? Or would it continue its steady decline? The data provided in 2005 was pretty clear to an analytical eye, but I didn’t yet think it was dramatic or conclusive enough to bring to the table. So I kept waiting and watching.
Then, in 2007, something dramatic did happen. Total minimum sea ice coverage fell from an average of about 5.4 million square kilometers to around 2.8 million square kilometers (according to Cryosphere Today data). The stunning decline cut the average low nearly in half! From 2006, the total drop in sea ice minimum was about 30%. The satellite showed an anemic ice cap that seemed to be hugging Greenland and the Canadian archipelago for safety. It had happened in just one year. In one year! It’s worth repeating for one important reason. Most climate scientists, up until that point, had assured the public that any human-caused climate change would be steady, gradual, occurring over vast time scales with almost imperceptible changes. To the unbiased observer, a 30% drop in Arctic ice coverage in one year is anything but gradual. It was sudden. It was explosive. It was a little scary.
In that one year all my remaining skepticism vanished with that giant chunk of ice cap. Increased levels of carbon dioxide, as measured each year at the Mauna Loa Observatory, was the only visible forcing on the earth’s climate system that could create the heat energy needed to melt so much ice so suddenly. Average solar activity was going down, which would have a cooling effect. There was no other legitimate forcing mechanism for warming on the radar. Furthermore, this melt had occurred at a time when temperature increases were in the range of .6 degrees Celsius about the 1900 average and .4 degrees Celsius above the 1950-1981 average. This seemed a small amount at the time. But what it didn’t show was how much more temperatures would have to rise to balance the earth’s climate at the then 370 ppm (parts per million) CO2 or how much the earth itself would have to change in response to that new balance. What became stunningly clear in 2007 was that shifts toward that new balance could be stunningly, dangerously rapid. NASA scientist James Hansen would later expand on this idea stating that natural forces were usually more gradual but that the human-caused increases in CO2 created a forcing on the climate system an order of magnitude greater than most effects in nature. To paraphrase Hansen – the human forcing packs one heck of a punch. And in 2007, that punch knocked out 30% of the Arctic ice cap’s coverage.I went to my friends and family. I began to do my best to spread the word. I wrote an article on my novel website’s blog and bulletined it through the social networks. The results ranged from loss of followers, to glazed-eyed denial, to outright personal attacks. But I hope my minor re-publication of the Cryosphere data had an impact, that it got people considering and acting. That, perhaps, a few more took up the cry who wouldn’t have otherwise. I honestly have no way of knowing. What I did learn is that denial is as insidious as it is numbing. A denier will do all possible to avoid the truth and then, when a change of mind happens, never admit they denied the thing in the first place. In some cases this behavior is simply smug obstinance. In others, it is a condition I like to think of as ‘steady state mind.’ People like to stay within their comfort zones and a part of this perspective often includes the assumption that they are mostly correct about their view of the world. In some ways, we all do this to greater or lesser degrees. It is only natural. For how can a person ever be correct on all counts? How could a person act with confidence without making a certain number of assumptions? But in the case of climate change (or any other imminent danger) it creates a deadly inertia. A barrier to understanding and necessary action. When fed by plausible misinformation, or worse, fear, such mental inertia can become intractable even to obvious proofs. It was once said ‘The Titanic is Unsinkable’ and many believed the comforting, mortal falsehood. And in the same vein, many of us now believe ‘All climate change is natural; humankind is too small to cause it.’ Such is the current state of climate change denial. Many who hold this view are people I care about.
So after the 2007 melt, what I now think of as the first ‘big proof,’ I began to dig in for the long haul, to draw battle lines in my mind. I’d made my first push to do my part, by trying to spread the word. But now I had to do more. I had to arm myself with the best, most useful, available information. So I expanded my search. I read a number of books both by deniers and by the scientists on the cutting edge of climate research. Those like James Hansen, whose life’s work has been the study of climate systems, proved invaluable sources. I dug into paleoclimate (a study of Earth’s past climates) and found that even natural climate change could be deadly quick once certain irreversible tipping points were reached. Of particular interest were the rapid development of ice damns on the giant glaciers of the last ice age and their explosive expulsion of water creating great waves and floods that roared across our planet’s surface. Some of the evidence was found in ten-thousand-year-old petrified trees, embedded horizontally in rock strata hundreds of feet above sea level on some Russian islands. Evidence, some archeologists noted, of a massive wave that swept out from the Laurentide Ice Sheet in Canada to inundate Alaska and deposit some of her trees on the facing shores of islands hundreds of miles away. Evidence mounted. Nature was massive. Tweek her a little and the world undergoes radical, sometimes unbelievably violent, change. But even more useful were new sources of information. The National Sea Ice Data Center (NSIDC) and the University of Washington’s Polar Ice Center section of the Applied Physics Lab (APL), became invaluable. NSIDC provided the most trusted source of information on sea ice using a variety of tools similar to the Cryosphere Today website but with great depth and factual analysis. Of particular interest on the NSIDC site was the tracking of remaining old Arctic sea ice. Old sea ice is ice that has remained for two or more years without melting. Indirectly, the volume of this old ice can be used to measure the ice sheet’s health overall. The more loss of old ice, the more unstable the ice cap. Looking at the measurements from NSIDC, showed old sea ice on a steady and rapid decline. More rapid, in recent years, than the decline of total sea ice coverage (See attached graphic).
But the kicker came when looking at sea ice volume as recorded by the Applied Physics Lab. The difference between sea ice volume and coverage is key. Coverage is the amount of sea ice visible on the ocean’s surface. Volume is the total measurement of coverage (surface area) times depth. Coverage measures ice in square kilometers. Volume measures ice in cubic kilometers. What this means is that measurements of sea ice coverage don’t take into account the total amount of ice-the portion beneath the visible ice at the surface. Measurements of sea volume showed a steady, unequivocal, and dramatic decline since 1980 (see graphic here). More dramatic, in many ways, than in observed sea ice coverage. Since 1980, according to APL data, average minimum sea ice volume has dropped from about 18,000 cubic kilometers to a dramatic low of 5,800 cubic kilometers in September of 2010 (about a 67% decline). What is most stunning about this decline rate is that, if it continues on this trend, the Artic reaches zero ice at minimum in 16 years. In little more than one and a half decades, according to APL data, late summer may show zero arctic sea ice.
In my mind, this set of data constitutes the second big proof. Though not visible on the surface, it makes pretty obvious sense. Anyone who has watched an ice cube melt in a glass knows that the underside of the cube melts more rapidly than the surface until what you end up with is a vanishing sliver. And both the APL data and NSIDC old sea ice measurements show that a similar kind of melt, but on a much larger scale, is occurring right now in our planet’s oceans.
At this point of observation, one feels an immediate sense of frustration. One does not want to be the engineer on the Titanic describing why it is inevitable the great ship will sink. In short, we don’t want to reach the third big proof – which would be the disappearance of late summer sea ice in the arctic. Why? Well, after that, things start to get more difficult. The first is that the earth’s reduced reflectivity caused by the ice sheet’s loss results in an increased warming. Dark oceans absorb more heat than white ice. Adding reduced reflectivity to an inexorably increasing concentration of CO2, makes it far more likely that the next big proofs (the scary ones) will follow: Greenland ice melt (#4), West Antarctic Ice Shelf ice melt (#5), and then release of methane bound up in water-ice formations called clathrates or ‘methane hydrates (#6).
A very rapid prognostication shows big proof #4 – melting of Greenland glacial ice, results in significant, dangerous rises in sea level. Same with big proof #5. The nightmare scenario for these melts is similar, but somewhat smaller, ice damning and water release events comparable to the end of the last ice age. But even a steady, non-violent melt resulting in sea level rise would be enough to flood many of the world’s major cities and wipe some nations clean off the planet (Maldives, Bangladesh and others). Big proof #6 – large releases of methane hydrates from the ocean floor result in massive loss of sea life due to ocean chemistry changes and significant increased climate forcings through greenhouse gas releases on top of those already produced by fossil fuel burning. The nightmare scenarios for methane hydrate releases are atmospheric fire storms caused by large methane ‘burps’ being ignited by lightning strikes and a runaway greenhouse effect resulting in Earth becoming more like Venus and less like the world that was the cradle of humankind.
So, for now, here we stand, still well away from that terrible, yet visible, end with two big proofs of our peril before us and with #3 waiting in the wings. We know the world is warming and we know the Arctic Ocean ice is inexorably thinning and shrinking. Our best scientists have provided us with the tools to understand why – human-caused greenhouse gas emissions bringing CO2 concentrations to 389 ppm and rising. It is beginning to dawn in the minds of some of us that the world we live in is already dramatically changed. Not the same world that sheltered human civilization for thousands of years. But a more unstable world. A place of violent storms and rising seas and more unpredictable weather. A tougher place. A place that can still sustain life and, if we’re lucky, human civilization. But not if we keep going. Not if we don’t change. Hopefully, the information before us will be enough to snap out of this comfortable denial and to demand rational action from our governments. To slow the ship down, to stop throwing coal on the fire, to steer clear of the worst storms of climate change, the ones that sink the ship and all the life-boats too.