Hot planet doesn’t cause hot wars

With U.N. Secretary General Ban Ki-moon attributing the ongoing conflict in Darfur to the loss of arable land brought on by global warming and scholars and American military planners warning that our hotter planet may see more conflict, the link between climate change and global security — especially on the African continent — seemed secure.

But a study published Monday by the Proceedings of the National Academy of Sciences argues that the majority of internecine conflicts are still driven by old-fashioned causes: grinding poverty, an entrenched elite depriving the local majority or minority basic needs, and adjustments to the global realignment of power brought on by the end of the Cold War. "The primary causes of civil war are political, not environmental," writes Halvard Buhuag, a political scientist with the Peace Research Institute, Oslo, Norway, who wrote the study.

"Countries with a larger share of the population excluded from influence over national power are more at risk of civil war," Buhaug reports. "Similarly, civil war risk is found to be inversely related to GDP per capita. Finally, we see that the baseline risk of civil war in Sub-Saharan Africa increased with the systemic change imposed by the collapse of the Cold War system."

The study challenges previous findings reported in the same journal last year. In October, a group of scholars, including U.C. Berkeley professor Marshall B. Burke, concluded that climate change was fueling conflicts, arguing that "warmer years [lead] to significant increases in the likelihood of war." The study suggested there would be a 54 percent increase in armed conflicts by 2003, leading to an additional 393,000 battle deaths.

But Buhuag challenges Burke’s methodology, arguing that climate has a minimal impact on climate. "Scientific claims about a systemic, correlational link between climate variability and civil war do not hold up to closer inspection," he writes. "The simple fact is this: climate characteristics and variability are unrelated to variations in civil war risk in Sub-Saharan Africa."

In interviews with the science magazine Nature, Buhuag and Burke quarreled over methodology. Buhuag maintains Burke’s study may have been "skewed by the choice of climate data sets, and by their narrow definition of ‘civil war’ as any year that saw more than 1,000 fatalities from intra-national conflict. The definition is at odds with conventional measures of civil war in the academic literature," says Buhaug: "If a conflict lasts for 10 years, but in only 3 of them the death toll exceeds 1,000, [Burke et. al] may code it as three different wars."

"You’d really like to apply as many complementary definitions as possible before proclaiming a robust correlation with climate change," Buhaug adds.

Burke maintains that his findings are robust, and counters that Buhaug has cherry-picked his data sets to support his own hypothesis.

Follow me on Twitter @columlynch