Climate change manifests itself in many forms: hotter temperatures, more extensive droughts, bigger floods, higher sea levels, more intense storms, and crazy weather in general. While climate change may be disinterested and mercurial, this does not translate to sexiness, and many people find reading about climate change to be a bore.

Now, a new working paper from the National Bureau of Economic Research has determined that climate change in the form of hotter weather leads to diminished “coital frequency."

Meaning that not only is climate change unsexy, but it's also bad for sex.

Economists from Tulane University, the University of California-Santa Barbara and the University of Central Florida used 80 years of U.S. fertility and temperature data to determine that when it's hotter than 80 degrees Fahrenheit, a significant decline in births occurs eight to ten months later. Furthermore they determined that these missing births, representing a 0.4% drop from the average, are not fully offset during ensuing cooler months.


"The lack of a full rebound suggests that increased temperatures due to climate change may reduce population growth rates in the coming century," write the researchers. "As an added cost, climate change will shift even more births to the summer months when third trimester exposure to dangerously high temperatures increases."

Their back-of-the-envelope calculations suggest that shifts towards summer births may lead to a 0.4% increase in the relative risk of low birth weight.

Assuming that climate change proceeds according to the most extreme scenarios—which hopefully it won't otherwise we're in for far bigger problems than being under-sexed—the researchers project that from 2070 to 2099, the U.S. may experience 64 more days above 80°F than the average taken from 1990 to 2002. This would effectively triple the number of average days above 80°F every year, which could result in a 2.6% decline in birth rates and 107,000 fewer babies born a year.


The economists worry, therefore, that climate change could make the already below-replacement birth rates in developed countries like the United States even worse. As for developing countries, they suggest the impacts on health and birth rates could be even worse.

However, there is a silver lining: the researchers conclude that air conditioning could save the day, and in a sense, save humanity.

"Based on our analysis of historical changes in the temperature-fertility relationship, we conclude air conditioning could be used to substantially offset the fertility costs of climate change," they write.


That is, if we can first work out the issues surrounding the large amount of fossil fuel energy that air conditioning demands, which further exacerbates the problem, causing the need for even more A/C therapy. The authors note this irony, stating that "the costs of increased air conditioning usage include increased greenhouse gas emissions, underscoring the fundamental dilemma in mitigating climate change impacts using energy-intensive technologies."

Alas, perhaps in the future we'll be able to invite someone over to "A/C and chill," if you know what I mean.