-- A Siegel (@A_Siegel) November 3, 2015
The National Bureau of Economic Research just published Maybe Next Month? Temperature Shocks, Climate Change, and Dynamic Adjustments in Birth Rates. In this study, economists Alan Barreca, Olivier Deschenes and Melanie Guldi look at the impact of "temperature shocks" on U.S. birth rates between 1931 and 2010. In short,
- If the temperature is above 80 degrees, birth rates nine months later are lower. [With implication that "sexual" intercourse goes down as well -- although, well, it could be impacts on fertility from sexual activity.]
- There is a rebound in following (cooler) months, but only about 30% -- leading to notable reduction in overall birth rates (projected 2.6% decline in U.S. birth rate).
- The delayed births -- generally representing shifts from summer to autumn conception -- occur in summer months, where there is a higher mortality and other health problems for babies (whether due to stress in pregnancy during higher heat or impacts directly on baby in summer months)
An economics perspective seems more focused on birth rate implications for economic performance (since a Dismal Science credo is that population growth = good).
As summers heat up, developed countries may see already low birth rates sink even lower. Plunging birth rates can play havoc with an economy. China's leaders recently acknowledged this by ditching the longtime one-child policy and doubling the number of children couples are allowed to have. A sub-replacement U.S. birthrate means fewer workers to pay Social Security benefits for retirees, among other consequences.
Non-economists might be more interested in the underlying point:
Climate change threatens sex.