"Climate change increases the likelihood of war and terrorism," President Obama said earlier this summer. The Pentagon and a distinguished committee of retired generals and admirals both produced reports earlier this year highlighting the accelerating risks of climate change to US national security. A recent Showtime series on climate change had Tom Friedman linking climate change to political instability in the Middle East.
But what is the basis of these claims? Do we have good evidence to support the connection between climate, conflict, and war? Not really.
For a start, there has been a spirited debate among researchers about the links between climate and violent conflict with a significant number of studies showing weak, non-existent, and even negative correlations between climate stress and conflict. For example, one set of researchers finds strong statistical links between higher temperatures and conflict in Africa between 1981 and 2002, and predict a 50% increase in conflict as a result of global warming. Others find weak or no relationships between temperatures, rainfall and conflict in parts of Africa, pointing out that other factors - such as poverty and poor governance - are much more important and that since 2002, conflict has decreased while climate hazards have become worse.
Another problem with many of the climate conflict studies is that they - or those that read them - confuse correlation with causation and make fundamental errors in the way they deal with space and time. And there is also the challenge of scale where a strong relationship at one scale of aggregation disappears when analyzed at another even though the individual data points are the same.
Some studies correlate country level data without controlling for the size of the country or its population, and find it difficult to account for how past conflicts and histories strongly influence the present. Even those that try to compensate for the varying size of countries by using an even grid struggle with the lack of geographically detailed data on climate, conflict and other factors.
The research studies that support the climatic basis of conflict also make some fundamental errors in research design. Rather than looking at the full range of climate extremes in a region and analyzing which of these led to conflict, which had no effect, and which led to cooperation, they instead look for conflicts and then try and link them back to climatic causes. For example, the prestigious journal Science recently published an article that claimed to analyze and synthesize more than 60 studies of climate and conflict, concluding that in the majority of cases the studies showed a robust link between climate and conflict. Although they had strict criteria for selecting the studies, to my mind there is a fundamental flaw in the experimental design. In only selecting cases where climate causes conflict it's not surprising that they, and other researchers, find proof of the relationship! Why didn't they broaden the study to see how many studies of climate impacts result in no conflict or cooperation?
To be sure this poses a challenge because although a number of groups collect data on international and domestic conflict, it is harder to corresponding data on incidents of peace and cooperation. But it should be possible to look at data on climate extremes and analyze the full range of responses to drought and other hazards including examples of cooperation, no response, and conflict - its already been done for water shortages to resolve debates over water wars.
Many researchers and policy makers became convinced that increasing competition over water would lead to conflict in regions such as the Middle East. But when geographer Aaron Wolf did a careful study of 189 river basins he found that in almost all cases, competition over water led to greater cooperation between nations and communities rather than conflict. Even in the case of Israel's relationship to their Arab neighbors Wolf's research shows that the Jordan River and other shared waters have been a source of peaceful resolution rather than serious conflict.
Where cooperation resulted in robust management institutions to manage shared waters, there is great potential to resolve the challenges posed by climate change. Across the world, many water management institutions are already preparing for climate change by commissioning studies, adjusting allocations, and rethinking infrastructure. On the Colorado River, the U.S. and Mexico recently agreed to more flexible arrangements to share flows during high and low years and to restore flows to the ecosystems of the Colorado delta. In Southeast Asia Cambodia, Laos, Thailand and Viet Nam are cooperating through the Mekong River Commission to adapt to climate change. These are just a few of the cases where climate change is prompting peaceful cooperation rather than violent conflict.
I was pleased that the most recent report of the Intergovernmental Panel on Climate Change provides a more nuanced analysis of climate change risks to security. The report draws on research studies that propose a focus on 'human security' rather than 'national security' - the risks that climate change poses to livelihoods, homes, and health. The authors conclude that the evidence on a climate connection to violence is inconclusive, including the literature that suggests that past climate changes have contributed to the collapse of civilizations and the argument that climate change and drought triggered the violence in Darfur in the last decade.
It is time for us to consider the possibility that climate change can trigger cooperation, not conflict. There are many examples of cooperation. We are in the third decade of worldwide intergovernmental cooperation to respond to the risks of climate change. We have a climate convention (UNFCCC) that has brought nations together to peacefully negotiate a shared solution to dealing with climate risks and an unprecedented series of international scientific assessments - the Intergovernmental Panel on Climate Change - that brings together thousands of researchers to communicate climate risks to policy makers. Despite criticisms of lack of progress, the climate negotiations have resulted in transfer of funds from richer to poorer countries, collective efforts to reduce emissions, and intensive collaboration to understand the causes and consequences of climate change. And when climatic disasters strike, such as Hurricane Haiyan, we see outpourings of humanitarian response founded in the long tradition of cooperation across international boundaries in response to hazards and the military helping with peaceful emergency response and recovery.
So, conflict or cooperation? To decide, we need better-designed studies, more rigorous analysis and less melodramatic claims. We need studies that hypothesize peaceful resolution to tensions connected to resource competition and climate change, and statistical studies that use research designs that are open to the possibilities that climate extremes might have no influence on conflict and might, in fact, have positive outcomes. Rather than raise fears of conflict, scholars and strategists should seek best practices for cooperative and peaceful responses to the stresses of climate change.