Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Stay on top of the latest market trends

Subscribe to Axios Markets for the latest market trends and economic insights. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Axios on your phone

Get breaking news and scoops on the go with the Axios app.

Download for free.

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Carnegie Mellon University just published an updated look at carbon emissions trends and data for the U.S. power sector that includes fourth-quarter and full-year 2017 information.

Expand chart
Data: Carnegie Mellon University Power Sector Carbon Index; Chart: Axios Visuals

Why it matters: It gauges progress in wringing heat-trapping gases from what was, until recently, the largest source of U.S. carbon dioxide emissions (but has now fallen behind transportation).

The big picture: Carnegie Mellon's Costa Samaras tells Axios that total power-sector CO2 emissions last year fell to their lowest level since 1988, and that 2017 joined 2016 as the first two years that more total power came from gas than coal.

What the new data shows:

  • "Total annual rolling CO2 emissions were 1,770 million metric tonnes, which was 27% lower than in 2005," a summary notes.
  • The measure of emissions intensity — that is, pollution per unit of energy output — shows that emissions in Q4 were 952 pounds of CO2 per megawatt hour, which is 4% below Q4 of 2016 and 28% below 2005 levels.
  • Total power generation was up 2% in Q4 compared with a year earlier, though coal-fired output was down 6%.
  • A few more comparisons of Q4 2017 to the same stretch in 2016: Natural gas was up 4%, wind generation rose by 13% and solar went up by 30%.
  • To be sure: The renewables are growing from a small base. Wind and solar combined were 9% of U.S. generation in Q4.

Go deeper

Updated 59 mins ago - Sports

Olympics dashboard

📺: The Olympic events to watch today; Olympics opening ceremony ratings plunge

🏊: Athlete spotlight — Katie Ledecky adds to Games career medals haul; Caeleb Dressel leads Team USA to gold.

🏀: U.S. Men's basketball suffers first Olympic loss since 2004

🤖: The robot Olympics

🚨: Heat wave brings scorching temperatures to Tokyo Olympics

🎤: Meet the new faces of NBC's Olympics coverage

Go deeper: Full Axios coverage

2 hours ago - Sports

Olympics opening ceremony ratings fall to 33-year low

Wally Skalij /Los Angeles Times via Getty Images

Ratings for the Olympic Games opening ceremony were down 36% compared to 2016, according to preliminary numbers from NBC Universal. 

Why it matters: The figures for the Tokyo Games event mark the lowest audience for an Olympics opening ceremony event in over three decades, per Reuters.

California's largest wildfire razes homes as 86 huge blazes burn in West

A burnt Corvette smolders at a property during the Dixie Fire in the Indian Falls area of unincorporated Plumas County on July 25. Photo: Josh Edelson/AFP via Getty Images

California's biggest wildfire merged with another blaze as it razed homes in a remote region in the state's north Sunday.

The big picture: The Dixie Fire, which erupted July 14 near the origin of the deadly 2018 Camp Fire in Butte County, is one of 86 large wildfires burning across the U.S. West.