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How strong is the connection between climate change and Brexit?

Spokesperson from climate change think tank in Virginia takes issue with editorial in the Clearwater Times
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Graphs from a study in Proceedings of the National Academy of Sciences (PNAS) shows trends for Syria since 1900. Graph A shows six-month winter rainfall; B shows annual temperature; C shows annual soil moisture; and D shows total population. Red lines show annual trend

by E. Calvin Beisner

Re: Editorial by Keith McNeill titled “Brexit vote is result of climate refugee crisis” in June 30 issue.

The influx of immigrants undoubtedly contributed to Brexit. Climate change, in turn, has been called an important driver of migration from Syria, and consequently a significant cause of Brexit.

The article “Climate change in the Fertile Crescent and implications of the recent Syrian drought,” PNAS, March 2, 2015, summarized its findings: “the 2007−2010 drought contributed to the conflict in Syria. It was the worst drought in the instrumental record, causing widespread crop failure and a mass migration of farming families to urban centers.”

Its summary concluded, “human influences on the climate system are implicated in the current Syrian conflict”—which produces refugees.

But the case isn’t solid.

A graph in the paper suggests that in the Fertile Crescent, which includes Syria, the Palmer Drought Severity Index (a scale from +3 to -3) worsened from about positive 0.2 to about negative 0.8 since 1930. That’s not enough to explain the severe 2007–2010 drought.

So what caused the drought?

Since 1930, the Fertile Crescent experienced about a seven per cent decline in winter rainfall and about 0.5 C˚ rise in annual surface temperature, both mostly before 1980, leaving little during the period of allegedly manmade warming, post-1980 – not enough to explain the drought.

Again, what caused the drought, and, more importantly, the conflict over water? It helps to understand that “drought” designates not necessarily a time of low precipitation but a time of water shortage – which can be caused by increased consumption or accelerated runoff.

Retired U.S. Navy Rear Admiral David Titley, meteorologist and professor at Pennsylvania State University, explained that after decades of poor water policy “there was no resilience left in the system” and “you just set everything up for something really bad to happen” – like ISIS.

So in addition to slight temperature rise and precipitation decline, another cause of drought was poor water policy.

But there’s another, more important cause. From 1930 to 2010, Syria’s population multiplied 11 times, and its industrial and agricultural water use multiplied even more, driving greatly increased water consumption – and hence shortages – even with no change in temperature or rainfall.

But even if higher temperature and lower rainfall drove the drought, what caused those? The Intergovernmental Panel on Climate Change concluded in its report on extreme weather that it was impossible to demonstrate a connection between global warming and frequency or severity of extreme weather events, including droughts.

Even if global warming contributed to rising temperature and declining rainfall, human activity needn’t have driven it. The computer models on which the IPCC depends simulate warming from rising atmospheric CO2 at two to three times the observed rate, and none simulated the absence of observed warming from early 1997 to late 2015. So they are tenuous reason to believe human activity was the main driver.

At most, human activity contributed a fraction of observed warming, so only a fraction of the rise in temperature and decline in rainfall, and only a fraction of that to the drought, and a fraction of that to the conflict over water.

In short, rising population and expanding industry and agriculture were greater causes of Syrian conflict than climate change, and religio-political conflicts dwarf them as causes of Syria’s civil war, the rise of ISIS, and the refugee crisis – which was but one among many reasons for Brexit.

Did a “climate refugee crisis” influence Brexit? Only slightly, at most.

Author E. Calvin Beisner, Ph.D., is founder and national spokesman of The Cornwall Alliance for the Stewardship of Creation in Burke, Virginia.