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Humanitarian Crises Are Visible From Space, Thanks to Changes in Earth's Atmosphere

ByAllison EckNOVA NextNOVA Next

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The story of the Middle East may be embedded in the region’s atmosphere.

A new

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study published the journal Science indicates that geopolitical strife, including the ascent of ISIS, is correlated with changes in local air pollution.

Jos Lelieveld of the Max Planck Institute for Chemistry and his team used the Ozone Monitoring Instrument aboard NASA’s Aura satellite to compare 2005-2014 trends in nitrogen dioxide and sulphur dioxide levels—gases linked to smog, climate change, and acid rain—against data measuring societal fluctuations during the same time period. What they found was that between 2005 and 2010, emissions increased, but between 2010 and 2014 (as the Islamic State rose to power and international trade sanctions were introduced) these nitrogen oxide levels rapidly declined.

Space-based observations of cities like Baghdad, Iraq could help scientists assess the severity of civil discord and effectiveness of economic sanctions.

The results may not be entirely surprising, since war squelches economic and therefore industrial activity. But the researchers say that what’s impressive is the extent to which pollution patterns are predictive of what’s happening on the ground. In some cases, these correlations are alarmingly specific. Here’s John Schwartz, writing for The New York Times:

International sanctions against Iran, he noted, caused an economic downturn that correlated with a steep drop in the pollutants after 2010. Nitrogen dioxide levels rose in Iraq after the war but have decreased sharply around the cities of Baghdad, Samarra and Tikrit with the rise of the Islamic State and its effect on the regional economy.

Uprisings in Syria could be tied to lower nitrogen dioxide levels over cities like Damascus and Aleppo; the Lebanese cities Beirut and Tripoli experienced increases in nitrogen dioxide levels that correlated with an influx of Syrians fleeing unrest. Public turmoil in Egypt can be associated with its decline in air pollution since 2011, he said.

Of course, we shouldn’t treat this finding as a silver lining of war: “It is tragic that some of the observed recent negative NO 2 trends are associated with humanitarian catastrophes,” the authors write. Plus, dangerous chemicals from modern weapons of war certainly aren’t benefitting the atmosphere.

Cities outside the Middle East respond to this new data-collecting technique, as well. For example, in Athens, nitrogen dioxide has dropped 40% since 2008 as the Greek economy has plummeted. In future analyses, the scientists will need to consider overall shifts in weather to solidify their conclusions.

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Photo credit: NASA Visible Earth