Arguments over whether climate change is real, and if so whether it is man-caused, ignore the elephant in the room.  That’s because any significant alteration of human behavior to reduce long-term catastrophic effects of climate change would interfere with someone’s quarterly bottom line—and someone else’s daily consumerism.  As detailed below, Solomon Hsiang received a scientific award for statistical analysis of human behavior as influenced by climate change.  The published analysis drew fire from outside the scientific circles.  Thus, the argument about the Hsiang team’s statistical conclusions becomes not data-driven, but belief-driven.  When data conflict with belief, the response becomes defensive because the data are seen as an attack, rather than as information.

Soloman Hsiang recently received an award from the American Geophysical Union.  (That’s the professional association of some 63,000 earth and space scientists, not a labor group.)  Hsiang and his colleagues at the University of California processed historical data to show that violent human conflict and social stability have been associated with climate changes, both on a local and on a national scale.  Based on the data, the authors concluded that the expected increasing global temperatures and changes in rainfall might exacerbate future violent conflicts.

I see an intuitive argument in agreement with the authors.  IF the climate heats up, or if wet areas go dry and dry areas get wet, I might expect people to become testy.  Climatic changes would bring disruption in food, water, population, incomes, and immigration, thereby creating tension among neighbors, pressures on politicians, and struggles between nations.  Others disagree with my intuitive argument.  The publications by Hsiang and colleagues set off a global argument.

I can understand that scientific arguments might arise concerning Hsiang’s statistical methods, but some of the objections look like political vehemence, characteristic of the political battle between climate believers and climate deniers.

What public arguments oppose Hsiang et al?  The German newspaper, Spiegel International, cited at length the criticisms of Hsiang’s statistical methods and selections of data.  That’s fair, but the rest of the article wasn’t.  Spiegel cast an aspersion on the Hsiang team’s motivations with the bold heading, “Good for their Careers,” above a paragraph of climate-denier talk.  Spiegel’s long article said that prior studies lacked firm conclusions, therefore, it was “astounding” that the Hsiang paper “appeared in the respected journal Science.”  Spiegel repeated alarming headlines from other popular media.  The article fairly cited the Hsiang team’s rebuttals of technical criticism, but then spent a paragraph citing a sarcastic blog claiming the Hsiang study is “Complete and utter nonsense.”

What did Hsiang and colleagues really do?  The authors examined 50 previous published studies of conflicts and concurrent temperature or climate changes.  They found, for each standard deviation increase in temperature or change in rainfall, personal violence rose by 4% and group conflict (civil war etc.) rose by 14%.  (Standard deviation measures the variation above and below an average.)  This result is a statistical correlation.  It doesn’t prove cause and effect.  However, the authors explain the methods they used to exclude confounding relationships and thereby conclude that temperature and moisture changes cause conflicts, directly or indirectly.

We will never know whether the team’s conclusions are right or wrong.  If persons, regions, or nations fight, it will be difficult to prove that the combatants are influenced by the change in climate.  However, ongoing climate change is an established fact.  Long-ignored data are unspoken facts that everyone ignores, the elephant in the room.  Denial becomes vociferous only when someone notices the smell.

Hsiang and company  processed the information.  The American Geophysical Union thought the work extraordinarily meritorious.  I suggest the AGU is a better technical judge than Spiegel and the other newspapers that feature spectacular headlines like “Global Warming Is Greatly Increasing Crime and Other Conflict,” cited from The Huffington Post.