About an hour east of Aleppo lies a low tell called Umm El-Marra. From the distance it is an indistinct feature lying in the relatively arid Jabbul Plain. The tell is hot, dry and dusty, On closer inspection it has much to reveal about the early history of northern Syria. Deep below the soft sediment deposited over milennia, Glenn Schwartz and his team have uncovered the remains of a bronze age city- including apparently royal burials associated with sacrificial offerings. The interesting thing that brought us here to see the site and speak with Glenn is the evidence that this city, like many others in northern Syria, declined or was perhaps abandoned around 2200 BC. At that time the city appears to have been an outpost of the world’s first empire, the Akkadian Empire. Interestingly, paleoclimatic evidence suggests that the timing of decline corresponds to a large and protracted drought. Was an unprecedented mega-drought a sufficient perturbation to cause such a widespread decline in urban culture? The questions remains debated in terms of Umm El-Marra. Gazing at the tell and surrounding country side one wonders, where would such a drought lead to today?
Glen Sproul dit MacDonald 
This is really interesting stuff, Glen! Glad your trip is working out well. Love the pictures!
Your posts have also gotten me thinking about the magnitude of drought that would be necessary for some serious migrations/mortality to occur today. Clearly poor groups and those less ‘linked in’ to the global community would stand to suffer the most, and political borders would greatly inhibit their attempts to seek more water/more arable land. Such a dramatic situation would probably only occur with a drought much more serious than any we have been in the recent past, but I do think that we will soon see a decline in agriculture in some parts of the World that are very susceptible to drought. This will not only generate clear concerns for starvation in less economically/agriculturally stable parts of the world, it will probably lead to some questions dealing with national security, very much like oil and other more scarce resources engender this kind of conversation today.
It is for reasons such as these that I think that warming over the next 20-100 years will be less about the actual temperature rise, and more about the water re-distribution.