Rick Stevens / AP

By the year 2100, 74% of people on Earth may be exposed to deadly heat waves if nothing is done to address climate change, according to a new study published in Nature. Researchers found that 30% of the world's population is currently at risk from deadly heat and even if we begin to drastically reduce greenhouse gas emissions, 50% will still be at risk.

The study: Lead author Camilo Mora and a team of researchers examined nearly 2,000 case studies between 1980 and 2014 where people died from extreme heat. They then collected climate data from the times and locations of each incident, including temperature, humidity, solar radiation, and wind speed.

The heat threshold: The scientists concluded that when combined with high humidity, moderate temperatures around 90 degrees Fahrenheit became deadly, while continual exposure to conditions above body temperature, 96.8 degrees Fahrenheit, is dangerous. When our bodies get above 104 degrees Fahrenheit, cellular machinery begins to break down, and anything above that requires immediate medical attention.

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7 hours ago - Health

Fauci says if people won't wear masks, maybe it should be mandated

Anthony Fauci. Photo: Graeme Jennings- Pool/Getty Images

NIAID director Anthony Fauci told CNN on Friday evening that if "people are not wearing masks, then maybe we should be mandating it."

Why it matters: Fauci made the comments the same day the U.S. hit its highest daily COVID-19 case count since the pandemic began.

Harris to Black voters: Casting a ballot is about honoring your ancestors

Democratic vice presidential nominee Kamala Harris speaks at a "Get Out The Vote" rally at Morehouse College. Photo: Elijah Nouvelage/AFP via Getty Images

Sen. Kamala Harris appealed to Black voters in Georgia on Friday, urging them to "honor the ancestors" by casting ballots, and again calling President Trump a "racist."

Why it matters: The U.S. saw a significant decline in African-American voter turnout between 2012 and 2016, reaching its lowest point since 2000. Higher turnout among Black Americans this year could tip the balance in favor of Democrats in key battleground states, including Georgia.

Updated 7 hours ago - Politics & Policy

Coronavirus dashboard

Illustration: Aïda Amer/Axios

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  5. World: Spain and France exceed 1 million cases.