|Although not nearly as important a crop as wheat, I included lentils in this graph to show how the drought affected other crops as well. I had to multiply the production in metric tonnes by 10 for the lentils to be legible. Data from the FAO|
For an in depth analysis that covers all the causes of the conflict, this Atlantic article by William R. Polk does a thorough job. Yet despite the many other factors at play, without the collapse of agricultural productivity, it's possible and even likely the drawn out conflict never would have happened.
To understand the severity of the drought, this quote from a 2010 Gary Nabhan article illustrates the biblical proportions of the event:
"In the past three years, 160 Syrian farming villages have been abandoned near Aleppo as crop failures have forced over 200,000 rural Syrians to leave for the cities. This news is distressing enough, but when put into a long-term perspective, its implications are staggering: many of these villages have been continuously farmed for 8000 years. As one expert puts it, this may be the worst long-term drought and most severe set of crop failures since agricultural civilizations began in the Fertile Crescent many millennia ago."
This USAID article on wheat production during the drought shows how there was "little to no measurable rainfall this year  in the planting period from October-December in the primary wheat producing regions of northeastern Syria".
The drought severly weakened Syria's ability to grow food. As farming became impossible entire regions lost their way of life. Men, families, or "entire villages" as Gary Nabhan recounts, were forced to leave their land and head to Syria's major cities. Most of the displaced farmers were from predominantly Sunni regions. The Syrian political apparatus on the other hand was mainly Alawite. Whereas confronting the Assad regime would have been unthinkable before the drought, the desperate poverty many Sunnis now found themselves in meant they had nothing left to lose. In March 2011 demonstrations broke out in the city of Daraa and Syrian security forces responded violently, killing four people. Protests then spread throughout the country and breakdown of the state would soon follow.
Protests in Daraa
Although this is a story of severe environmental circumstances outside of human control, it is important not to conclude that Syrian state had no agency in the collapse of agricultural production. Indeed it was the well intentioned but short sighted development and poor management of irrigated agriculture, especially in the arid Northeast, which set Syria up for such a catastrophic disaster when drought did arrive. As this article by Francesca de Chatel explains:
... water policy in Syria has since the 1950s been driven by a supply-side approach with a specific focus on dam construction and irrigation projects in the north-east of the country. The relentless drive to increase agricultural output and expand irrigated agriculture blinded policy makers to the natural limits of the country's resources. Unrealistic agricultural targets, corruption, a failure to implement and enforce legislation, and the absence of a long-term strategy have thus devastated a region that was considered a breadbasket for Syria and the region.
Over the past 60 years, Syria's agricultural sector has undergone intensive development, particularly in the north-east of the country. The country's irrigated area has doubled over the past 20 years from 651,000 hectares in 1985 to 1.35 million hectares in 2010. Sixty per cent of this surface area is irrigated with groundwater, which is being extracted at an unsustainable rate. Ninety per cent of the country's water goes to agriculture, by far the highest percentage in the region, with very low irrigation efficiency. Over 80 per cent of irrigated land is still irrigated through traditional flooding methods and losses in the open concrete government irrigation canals range from 10 to 60 per cent.
(Sounds eerliy like the San Joaquin Valley.)
As with many states before it, Syria is yet another example of the perils that await when a nation's soil ceases to be productive. With climate change upon us, the type of drought which brought down the Syrian state are sure to be seen in increasing number. The importance of resilient, effiecient and realistic irrigation strategies, as well as healthy soils that can retain moisture better cannot be understated. These are not the distant goals of some far off agroecological utopia, they are steps that need to be taken immediately to prevent other states from degenerating into bloodshed.