How does the weather affect people’s rights? In an older post I cited a study claiming that colder temperatures in pre-modern Europe made persecution of Jewish communities more likely. The economic hardship resulting from cold weather in agrarian societies is one possible cause of rights violations, but perhaps not a very relevant one in our post-industrial societies faced with the risk of global warming. A warmer climate can also have an effect on rights. First, higher temperatures may increase irritability, aggression and interpersonal violence resulting in small scale rights violations. Perhaps there’s an added risk that this type of violence escalates and becomes group violence or even war. Second, global warming may have devastating economic effects: drought may decimate crops or reduce the inhabitable surface of the earth, and these consequences of warming may in turn cause tensions between population groups, tensions which can become violent conflicts.
The first effect is well documented. For example,
hotter US cities still yield significantly higher violence rates than cooler cities, even after statistically controlling for 12 social risk factors, including age, education, race, and economic factors. (source)
Whether or not this can escalate and morph into larger scale conflicts is less clear. There is this study which found an
increase in conflict associated with increasing surface temperature in locations that are temperate or warm on average. … [C]limate’s influence on security persists in both historical and modern periods, is generalizable to populations around the globe, arises from climatic events that are both rapid and gradual, and influences numerous types of conflict that range across all spatial scales. The majority of studies suggest that conflict increases and social stability decreases when temperatures are hot and precipitation is extreme, but in situations where average temperature is already temperate, anomalously low temperatures may also undermine stability.
And then there’s also this:
for each one standard deviation change in climate toward warmer temperatures or more extreme rainfall, the median effect was a 14 percent increase in conflict between groups, and a 4 percent increase in conflict between individuals. (source)
If this is correct, future climate change may be truly apocalyptic if we don’t learn to adapt. How exactly higher temperatures cause conflict is unclear. The effect of heat on individual temper seems an unlikely explanation for large scale conflict. Perhaps the effect is indirect: heat may for example reduce economic output, which in turn may make conflict more likely. Perhaps drought causes conflicts over land, which in turn may map upon pre-existing ethnic tensions.
For a criticism of the cited studies, go here. Additional doubts regarding these findings come from this paper which found that cold could stir up as much trouble as heat. Generally speaking, colder periods force more people to stay inside more of the time. That’s due to both the cold and the fact that the cold usually comes with more hours of darkness. Hence there’s a lower risk of interpersonal conflict such as assault or robbery. Tempers are also generally subdued when it’s cold. However, prolonged spells of coldness can in theory have similar economic effects as heat and drought, as is shown by the study of anti-Semitism in pre-modern Europe cited above.
It seems that it’s too early to be certain about the effect of the weather on rights violations. If there’s an effect, it’s not large enough to be immediately obvious, as is the case for other effects such as tyranny, poverty and war.