May 29, 2018

Study: Hotter temperatures hurt U.S. students

Students working on computers. Photo: David L. Ryan/The Boston Globe via Getty Images

Hotter temperatures cut academic achievement by inhibiting cognitive skill development, but more air conditioning in schools can mitigate those harms, new research on U.S. students shows.

Why it matters: The findings on how heat lowers the "productivity of instructional time" provides new data points on the effect of higher temperatures on human welfare and performance. (The National Bureau of Economic Research circulated the paper on Monday, and it can be downloaded here.) It concludes that air conditioning's economic benefits far outweigh installation and operation costs.

The findings:

  • "Without air conditioning, each 1° F increase in school year temperature reduces the amount learned that year by one percent," it finds.
  • "[W]e estimate that school air conditioning would offset over $25,000 per classroom per year in future lost earnings due to temperature increases predicted by climate change models," the study states.
  • It's authored by experts in economics and policy from Harvard's Kennedy School of Government, the College Board and elsewhere.

What they did: The paper explores 21 million test scores from around 10 million high school kids who took the PSAT exam at least twice, and combines it with local temperature data in the year preceding the test.

One troubling conclusion: "We argue that heat effects account for up to 13 percent of the U.S. racial achievement gap, both because black and Hispanic students live in hotter places than white students and because heat damages minority students’ achievement more than white students’ achievement," the paper notes.

The big picture: The paper adds another dimension to a thorny problem we wrote about recently — how expansion of air conditioning worldwide provides a major boost in human well-being but also could make global warming even worse thanks to increased energy demand.

  • "Understanding the causal relationship between cumulative heat exposure and learning is of heightened policy relevance in light of accelerating warming in most parts of the world, and given that the overwhelming majority of the world's population does not yet have access to air conditioning," the paper states.

Go deeper

Mass shooting in Milwaukee: What we know

Milwaukee Mayor Tom Barrett in 2012. Photo: John Gress/Corbis via Getty Images

Six people died in a shooting at the Molson Coors Brewing Company in Milwaukee on Wednesday, including the gunman, Mayor Tom Barrett told reporters at a Wednesday evening press conference with local police.

Details: All of the victims worked at the brewery complex, as did the shooter who died of "an apparent self-inflicted gunshot wound," police confirmed in a statement late Wednesday.

Go deeperArrowUpdated 7 hours ago - Politics & Policy

Coronavirus updates: South Korea case count tops 2,000

Data: The Center for Systems Science and Engineering at Johns Hopkins, the CDC, and China's Health Ministry. Note: China numbers are for the mainland only and U.S. numbers include repatriated citizens.

33 people in California have tested positive for the coronavirus, and health officials are monitoring 8,400 people who have recently returned from "points of concern," Gov. Gavin Newsom said Thursday.

The big picture: COVID-19 has killed more than 2,850 people and infected over 83,000 others in some 50 countries and territories. The novel coronavirus is now affecting every continent but Antarctica, and the WHO said Wednesday the number of new cases reported outside China has exceeded those inside the country for the first time.

Go deeperArrowUpdated 8 hours ago - Health

Syria's darkest chapter

Family room without a family, in Idlib. Photo: Muhammed Said/Anadolu Agency via Getty Images

The worst humanitarian crisis of Syria’s brutal civil war is colliding today with what could be the war’s most dangerous geopolitical showdown, after at least 29 Turkish troops were killed in an airstrike.

The big picture: The fighting is taking place in Idlib in northwest Syria, where a ferocious Syrian and Russian offensive has displaced 1 million civilians and infuriated Turkey, which borders the region.

Go deeperArrow10 hours ago - World