The Science of This Spring's Tornadoes

With the devastating Joplin, Missouri, twister arriving on the heels of April's deadly outbreak in the Southeast, many are wondering just what's in the air this spring. Are we in for more?

What's the Latest Development?

Only three weeks after an unprecedented series of twisters wrought destruction across the Southeast, residents of Joplin, Missouri, are still digging out from the destruction of a tornado. It is shaping up to be an unusually active year: "Over the last couple of decades, an average of about 1,200 tornadoes touched down each year in the continental United States. This year, about 1,076 had been counted even before this week's activity in Missouri and elsewhere." Experts say America's history of urban sprawl makes larger areas of land susceptible to tornadoes. 

What's the Big Idea?

What can explain this increase in tornado frequency and strength? "The Gulf of Mexico is warmer than normal, sending more moist air over the South. The jet stream has also been moving somewhat farther south than usual, bringing it into contact with that excess moisture and triggering the large storms. ... It is impossible to link specific storms and weather events to climate change. But one of the predictions of the climate change models is that we'll be in for more intense storms as average global temperatures climb. That is what appears to be happening, both in summer and in winter."

Is life after 75 worth living? This UPenn scholar doubts it.

What makes a life worth living as you grow older?

Culture & Religion
  • Dr. Ezekiel Emanuel revisits his essay on wanting to die at 75 years old.
  • The doctor believes that an old life filled with disability and lessened activity isn't worth living.
  • Activists believe his argument stinks of ageism, while advances in biohacking could render his point moot.
Keep reading Show less

Brazil's Amazon fires: How they started — and how you can help.

The Amazon Rainforest is often called "The Planet's Lungs."

Politics & Current Affairs
  • For weeks, fires have been burning in the Amazon rainforest in Brazil, likely started by farmers and ranchers.
  • Brazil's president, Jair Bolsonaro, has blamed NGOs for starting the flames, offering no evidence to support the claim.
  • There are small steps you can take to help curb deforestation in the Amazon rainforest, which produces about 20 percent of the world's oxygen.
Keep reading Show less

Study: Sending emojis is linked to scoring more dates, sex

Emojis might contain more emotional information than meets the eye.

Sex & Relationships
  • A new study shows that people who frequently used emojis in text messages with potential dates engaged in more sexual activity and had more contact with those dates.
  • However, the study only shows an association; it didn't establish causality.
  • The authors suggest that emojis might help to convey nuanced emotional information that's lacking in strictly text-based messaging.
Keep reading Show less