Monday, March 15, 2010

Doom versus Doom

kw: book reviews, nonfiction, climate change, polemics, science

The competition for the hearts and souls of America continues. The latest salvo in the Climate War is A World Without Ice by Henry Pollack, PhD, with a foreword by Al Gore. There is no mistaking which viewpoint Dr. Pollack supports, and after reading the book, I suspect he would object to my use of "viewpoint". To him, human-caused climate change is settled science.

The book, to be a book, needed something more than a couple of long essays about the science of climate change and its consequences. Here is a brief outline:
  • Two chapters of historical survey, one on the discovery of the Antarctic continent and the Arctic regions by Europeans and one on the occurrence of ice throughout the solar system.
  • Further history, of the ice ages of the past 2-3 million years.
  • A chapter "Warming Up" that covers the Holocene, the past 11-12 thousand years, including the "Little Ice Age" of 200 years ago and the Medieval Warm Period about a thousand years ago.
  • Chapters 5 and 6 detail the natural and human causes of climate change.
  • Then the consequences of a rise in the oceans.
  • Finally a survey of possible policies to mitigate the human consequences.
It is this last chapter that I find very salutary. While the author's tone is frequently angry, he takes a realistic look at possible futures, and urges us to actions that might genuinely help. Far too many books have taken the attitude "We have to stop this battleship on a dime". Knowing that such a thing is not possible, Dr. Pollack discusses steps we can take to survive what must come, and to keep more of it from coming.

One key to understanding what we have to work with emerges from graphs like the following, based on data found here (and see Lisiecki, L. E. and M. E. Raymo (2005). A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records. Paleoceanography 20: PA1003).
The past seven ice age cold cycles have occurred on a 100,000-year schedule, while earlier ones came about every 41,000 years, beginning about 2.9 million years ago. If this graph is accurate (always a concern), three of the last four warm cycles have gotten warmer than the present (Holocene) epoch has to date.

As concerns agriculture, 100,000 years or so is not enough time for significant new species to arise. The species that exist today have weathered at least a cycle or two of cooling and warming. However, our over-tuned cereal varieties are probably less robust and will need our care—and possible augmentation from non-domestic varieties—to continue to produce well in a changed climate.

The author correctly identifies sea level changes as the most significant effect, in human terms. Whether climate change occurs naturally or is human-caused, warming is warming, and water is water, and ice is ice: unless we enter an ice age cooling cycle, things are going to get warmer, and the water is going to rise. There is little agreement as to whether certain regions will benefit or not from changes in yearly temperature and shifting rainfall patterns (though I think investing in Canadian farmland might be a good idea).

The author directs his argument against what he calls "four trenches", as though this were warfare on the WWI model. The four levels of denial have been:
  • To deny that the instrumental records are accurate, or have been interpreted properly, primarily to account for cities warming their surroundings. (This is countered by noting that 3/4 of Earth's area is ocean, and no cities have been built at sea.)
  • To deny that humans have a significant effect. (I personally think the amount of human causation is being overstated, but this is beside the point, if warming is occurring.)
  • To state that warming and more carbon dioxide will help agriculture. (Maybe so, maybe not. Crops might benefit in some areas but greater heat may cause more heat stress, countering the benefits of more access to carbon dioxide.)
  • To claim that it will cost too much. (I have a story as an analogy. A friend has no health insurance, and says she cannot afford it. I showed her that she cannot afford to be treated at any hospital unless she has insurance. "Eat hot dogs, but get insured.")
It is time to quit pointing blame and to plan for the future. I particularly appreciate this aspect of the author's message.

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