Last November, Presidential candidate Bernie Sanders raised some eyebrows when he said, “…climate change is directly related to the growth of terrorism. If we do not get our act together and listen to what the scientists say, you’re gonna see countries all over the world — this is what the CIA says — they’re going to be struggling over limited amounts of water, limited amounts of land to grow their crops, and you’re going to see all kinds of international conflict.”

Since then, a number of media outlets have fact-checked this statement, and PolitiFact has rated this comment as being Mostly False. You can read about PolitiFact’s full analysis here.

While Sanders’s comments were perhaps too direct in establishing a causality relationship between climate change and terrorism, he’s not alone in connecting the impact of climate change as a destabilizing force that terrorist organizations can take advantage of. The Defense Department mentions climate change as a “threat multiplier” in a 2014 report, and Al Gore has been quoted numerous times how the Syrian Civil War was caused by extreme drought conditions, which were caused by climate change.

While intuitively, these arguments make logical sense, other than anecdotal one-off instances (i.e. drought in Syria led to Syrian Civil War, drought in Nigeria led to Boko Haram, etc.), what has lacked is a comprehensive review of extreme weather conditions globally in recent years, and whether geographies facing the worst impact of climate change has seen an increase in terrorist activities. Based on Sanders’s statements, this seems like a reasonable assumption to make.

The first place to look was at where climate change was hitting the hardest in recent history. Mapped below is a heatmap of the impact of extreme weather events on the population. The higher number, the great percentage of the population that has been impacted by extreme weather such as drought, floods, etc.

Data source: IMF. Extreme weather impact on percentage of population, 1990-2009

An interactive version of the map is here: https://public.tableau.com/profile/publish/Apr11/Story1#!/publish-confirm

Swaziland, Malawi, China, Niger, and Eritrea are countries who have populations most impacted by severe weather conditions. If Sanders’s comments hold true, we should also see the highest number of terrorist activities in those countries in recent history. Mapped below is the number of casualties from terrorist incidents since 1980. Casualties were plotted here instead of number of incidents to show the severity of terrorist activity.

https://public.tableau.com/views/Terrorismvs_GDP/Dashboard1?:embed=y&:display_count=yes

It is immediately apparent that those 5 countries do not have anywhere near the highest number of terrorist casualties in the past two to three decades.

Also included in the interactive map for context is the percentage change in GDP year over year to potentially show the amplifier impact of climate change, as well as poor economic conditions on terrorist activity. However, based on the data that is presented, no direct relationship can be easily seen between both climate change, and economic health on terrorist activity. Sanders’s comments don’t hold up against the data. Instead, as Time and PolitiFact have indicated, there seems to be many other factors that contribute towards terrorist incidents.