The main title of The Ice at the End of the World: An Epic Journey into Greenland's Buried Past and our Perilous Future, by Jon Gertner, embodies a double entendre. Even today, to be in the middle of the Greenland ice sheet puts you at a "pole of inaccessibility", really at the end of the Earth; and what happens to that ice could indeed portend the end of the world (though not the Earth).
World versus Earth: The Earth is the physical planet, "third rock from the Sun", from its core to the edge of the atmosphere a few thousand miles above the surface, including the biosphere, of course. The world is the collection of human civilizations and systems that form the environment for human life and living. The Earth is incredibly robust. The biosphere is very robust. The world is fragile. Even the much-vaunted "western world" that provides comfort, sustenance, and amazing conveniences to about one-third of the total human population, is remarkably fragile.
About a tenth of the world population, nearly 700 million, lives at or below an elevation of 10m above sea level. For every meter of sea level rise, about a tenth of these (more at first, fewer later) will have to move uphill. But the three laws of real estate value, "location, location, location", meaning "higher ground for better view (except for that seaside vacation home!), close to conveniences (stores, etc.), and close to work" will drive costs up, and up and up.
The Ice at the End starts with the history of the exploration of Greenland. While it is called the largest island, I think of it as the smallest continent. It is nearly 1/3 the size of Australia, and is about 3 times the size of the New Guinea island. Being mostly covered with an ice cap about two miles thick makes its exploration extremely arduous at best, any time prior to the use of aircraft and tracked heavy vehicles; now it is merely "very arduous". One of my favorite turn-of-the century scientists, Alfred Wegener, died there at age 50, in 1930.
Once the early explorers, combining European and Inuit materials and methods, showed it is possible to cross the ice sheet, scientists made up a growing proportion of "visitors", a proportion that exploded once the American military began pouring money into Arctic exploration right after World War II. Now the ice volume can be measured daily by satellite, on-ice expeditions can continue to determine snowfall accumulation and compaction rates, and ice cores have been drilled to bedrock in a few locations. Now the true significance of Greenland and its ice are becoming clear.
To cut to the chase: Even if we ignore Antarctica, progressive melting of Greenland's ice alone can cause catastrophic damage to the infrastructure of every nation that has a coastline (nearly all of them). I gathered a number of calculated amounts for the amount of water in that ice. If it were all put into the ocean at once, without heating up beyond melting temperature, the seas would rise by 27 feet, or 8.2 meters. Then, as it warmed to the 40°F (4°C) average temperature of the ocean, sea level would rise about another couple of inches (5-6 cm).
Compare that to current rates. Since the 1960's, sea level has risen between 3 and 3.3 mm/yr. About a third of that is from Greenland, about half from ocean thermal expansion, and the rest from Antarctica, mainly the Thwaites glacier and a few lesser ones. See this montage:
The four images of Greenland plus Iceland were made in December of 1984, 1994, 2004, and 2014, from left to right. It may be hard to see the decrease in ice cover from decade to decade. The total difference in ice volume over these thirty years is 0.75%. Here is a closeup of the northeast quadrant, where the difference is more evident:
On first sight, one may say, "It's just a difference in snow cover," but with a careful look, one may see that the ice front has also receded, and we need to note that the entire ice sheet has gotten thinner by more than a half percent (30 ft or 9.5 m) in that time. Over that same interval the sea has risen nearly 100mm, or 4". And a third of that was Greenland's ice melting, over and above the snow that fell.
Though I am a political/social conservative, I have long known of the greenhouse effect, and what it can do to this planet. Will rising temperatures and rising seas drive human life off the Earth? That isn't likely. However, those phenomena will drive humans inland everywhere, and will likely eliminate a few oceanic nations such as the Maldives, Palau and Tuvalu. Of continental nations, Bangladesh would be one of the hardest hit: a quarter of its land area is below an elevation of 8m.
I have always been in favor of research into renewable energy, primarily solar. At present levels of efficiency, it would take less than 200,000 square miles (500,000 sq km) of solar panels to meet all energy needs for the world. That's about the area of Spain, but it would be spread everywhere, mainly within 40° of the equator. This needs to be coupled with better batteries to take care of cloudy days. At present prices, the investment would be huge, something like 200 times the world yearly GDP. However, research also results in lower prices, which can only help.
Someone who denies the importance of climate change would call this book a polemic. I do not. It is even-handed and factual, without the shrillness that pervades so much public discourse on the subject. I learned some great history and gained a better perspective on the importance of Greenland in the total ice/water/ocean budget of the planet. I recommend the book, no matter what your political stance.
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1 comment:
When I began this post I intended to speculate that in a century or so Greenland could become an agricultural powerhouse. Thus the post's title. By the time I was ready to publish it I had forgotten that. Just by the bye, though, in another generation or two, don't be surprised if Siberia becomes prime agricultural land!
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