Can the weather cause war? The latest issue of Nature seems to suggest as much. Featured was an interesting article [1] which explored the relationship of El Nino/La Nina weather patterns and conflict events over the past 50 years. El Nino/La Nina (ENSO) is an ill-understood weather phenomena characterized by 5 year cycles of warming/cooling due to fluctuations in warm/cool air pressure. It is usually associated with extreme weather events. Assocations with ENSO have been found for a number of climate related phenomena including hurricanes, rain fall and influenza infection and mortality patterns.

The researchers link the Onset and Duration of Intrastate Conflict [2]dataset with available ENSO data. They find strong associations of ENSO events with conflict events worldwide. Anticipating that the associations may be driven entirely by conflicts in Sub-Saharan Africa, the researchers remove all African conflicts and still discover the same association.

One very interesting result is that the relationship of ENSO to conflict appears to fade away as a country’s GDP increases, though picks back up again for extremely wealthy countries such as the United States. Apparently, it is to a country’s advantage to remain in the middle. Hsiang’s research is important because it mostly confirms that which was already suspected by a number of conflict specialists, namely that environment and human warfare are intimately related[3-11].

Poor countries are prone to food insecurity. A temporary drought, a massive tropical storm and even a small change in climate can result in a famine of broad proportions. It is, therefore, logical to assume that the poorest of countries would be the most sensitive to ENSO events. Middle income countries are able to weather temporary events and are wary to spend precious capital on waging wars. Wealthy countries such as the United States are sufficiently secure enough to deal with climate change and sudden weather events but have access to more than enough capital to wage conflicts to further their own resource and political interests.

Climate change, ever rising numbers of intense weather events, increasing population and declining access to water could theoretically turn the late 21st century into one of the bloodiest eras in human history. The rise of developing economies on the world stage, however, could help mitigate this effect as poor countries develop their internal food and transportation infrastructure. The mass resource grab presently being waged by rising middle income countries such as China, India, Brazil, South Korea and many mid-Eastern states could lead to an exported war of epic proportions, though. The future is uncertain, though, as it always is.

Governments around the world (including our own) are taking the issue of climate change and the possibility for civil and interstate conflict very seriously [12-14]. By all appearances, however, the American electorate and the US political scene is not.

1. Hsiang SM, Meng KC, Cane MA: Civil conflicts are associated with the global climate. Nature 2011, 476:438.
2. Strand H: Onset of Armed Conflict: A New List for the Period 1946–2004, with Applications.Technical report 2006.
3. Cool heads or heated conflicts? Climate change and warfare.(how to prevent climate-induced wars). The Economist (US) 2009, 393:82.
4. Anonymous: Climate and Conflict. FCNL Washington Newsletter 2010:2.
5. Ashley H: Climate change-related conflict forecast. The World Today 2008.
6. Drapeau MD, Mignone BK: Culture, conflict, and… climate? Science (New York, NY) 2007, 316:1564.
7. Lionel J, Hugh M, Neil M, Ian G: Climate change, ill health, and conflict. British medical journal 2011, 342:777.
8. Nordås R, Gleditsch NP: Climate change and conflict. POLITICAL GEOGRAPHY 2007, 26:627.
9. Sondorp E, Patel P: Climate change, conflict and health. Transactions of the Royal Society of Tropical Medicine and Hygiene 2003, 97:139.
10. Stephan H: Climate Change, Future Conflict and the Role of Climate Science. RUSI Journal 2005, 150:18.
11. Scheffran J: Climate-induced instabilities and conflicts. IOP Conference Series: Earth and Environmental Science 2009, 6:562010.
12. CNA: National Security and the Threat of Climate Change. 2007.
13. Impacts, Adaptation and Vulnerability. In Intergovernmental Panel on Climate Change; 2007.
14. Barnett J, Adger WN: Climate change, human security and violent conflict. POLITICAL GEOGRAPHY 2007, 26:639.