By Dr. Colin Kelley, Senior Research Fellow, The Center for Climate and Security
A new study provides the strongest evidence to date that the drying of the eastern Mediterranean Levant region over recent decades is very likely the result of human influence on the Earth’s climate system. This research uses tree-ring data in the Old World Drought Atlas to better characterize year-to-year and decade-to-decade natural rainfall variability over the greater Mediterranean basin.
The authors, led by Ben Cook, a climate scientist at NASA’s Goddard Institute for Space Studies and the Lamont Doherty Earth Observatory at Columbia University in New York City, conclude with high confidence that the recent extended drought in the Levant is well outside the range of natural variability over the last 900 years. The recent drying trend as measured by the tree rings is very much in agreement with not only measurements of rainfall using station data and satellites but also with simulations from global climate models that use the known increases in greenhouse gases during the observed record.
These changes also agree well with the current understanding of the mechanisms of subtropical drying globally due to human influence. In short, this new study is yet another significant piece of convergent evidence to show that human-induced climate change has already begun to demonstrate an important influence over this region. The global climate models, when forced with increasing greenhouse gases, predict that this region will continue to dry during this century.
These findings have particular importance for the nations in the Levant, including Cyprus, Israel, Jordan, Lebanon, Palestine, Syria and Turkey. The people who live in these nations are at the front lines of this trend, but the negative consequences don’t stop there. The world is currently experiencing a refugee crisis, and the primary contributor has been the conflict in Syria, which began in the wake of other “Arab Uprisings” in 2010 and 2011.
In 2012, a briefer by the Center for Climate and Security highlighted the possible connections between climate change, drought, natural resource mismanagement and instability in Syria, drawing on important research released in 2011 by NOAA and the United Nations Office for Disaster Risk Reduction (UNISDR). In 2015, my colleagues and I published a study in the Proceedings of the National Academy of Sciences which validated that briefer’s assessment of the role of climate change in the drought that occurred from 2006-2010, showing that the emerging climate change signal in the Fertile Crescent made that severe drought two to three times more likely. We showed this drought to be the most severe multiyear drought in the observed record for this region, and the drought’s results, coupled with natural resource mismanagement in Syria, would prove disastrous.
Syria was highly vulnerable at the onset of the drought for a number of important reasons. The first, and perhaps most important, was poor governance. Syria’s stability prior to the drought was strongly tied to its wheat production, which had been strongly encouraged by the government and had grown to represent 25% of its GDP. Because of the drought Syria abruptly went from being a net exporter of wheat to a net importer, relying heavily on world food prices that were high at the time. Two other critical factors, strongly related to each other, were population increase and groundwater decline. Syria’s population grew exponentially from around 5 million in 1950 to roughly 25 million in 2010 and its demand for water, crucial for consumption and for irrigation purposes, increased accordingly. This was exacerbated by highly water-intensive cotton and wheat production. As the demand for water increased, so did the rate of groundwater extraction. Declining groundwater is a huge problem globally but particularly in semi-arid and arid regions that are more dependent on it as a supplement to rainfall.
The recent drought in the Levant came on the heels of two other severe multiyear droughts in the late 1980s and 1990s, respectively, also strongly implying that such droughts are becoming not only more severe but more frequent under climate change. For Syria, the recent drought represented the final straw that pushed its farmers and herders beyond their threshold of resilience. The agriculture in the ‘breadbasket’ region collapsed, herders lost around 85% of their livestock, and many farming and pastoral families sought survival in the cities in Syria’s west. Overcrowding and a lack of adequate resources in these urban areas was the result. The Assad regime failed to meet the needs of the displaced population, estimated to be more than several hundred thousand and as many as 1.5 million people. In early 2011 the uprising occurred, followed by years of violent conflict.
As of this writing, a tentative ceasefire has been agreed upon, but Syria’s future is far from clear. What is clear, however, is that Syria’s civil war has had a profound effect on the rest of the world. Thus, Syria stands as a primary example of how climate change can combine with other key factors to exacerbate existing food and water security and social challenges and to push a vulnerable region beyond its resilience. As such, climate change has been taken very seriously for some time by the security communities, including Department of Defense.
This example perhaps begs the question of who will be the next Syria? Prior to the uprising, Syria was widely viewed by experts as stable and largely immune to the effects of the Arab Spring. According to a recent study by Femia, Werrell and Sternberg, certain popular indices of nation-state fragility corroborated this belief, but clearly this was not in fact the case. This leads to the conclusion that, while prediction of state failure or conflict is clearly a highly complex task involving numerous variables, there is strong reason to believe that closer examination of regional climate change and resource availability change could greatly improve existing state fragility indices, providing decision makers with the information necessary to make informed choices.