2019 wasn't just the second-hottest year on record — the 2010s will go down as the hottest decade in human memory, per a new report.

• The Copernicus Climate Change Service found "an unrelenting upward trend in temperatures as emissions of greenhouse gases trap heat in the atmosphere and change the climate," the N.Y. Times notes.

The big picture: "The amount of carbon dioxide in the atmosphere is now the highest level in human history and probably has not been seen on this planet for 3 million years," WashPost notes.

• "The year also brought troubling signs that natural systems [like permafrost and the Amazon] that serve to store huge quantities of carbon dioxide and methane ... may be faltering as temperatures increase."

By the numbers, per Copernicus:

• "The five warmest years on record have all occurred in the last 5 years."
• "Globally, the calendar year 2019 was 0.59°C warmer than the 1981–2010 average."
• "2016 is the warmest calendar year on record, with a global temperature 0.63°C above that for 1981–2010.
• "The third warmest calendar year, 2017, had a temperature 0.54°C above average."

What's next: November 2020 is shaping up to be a historic month on climate, Axios' Amy Harder reported.

• The UN's annual conference will offer the most high-profile moment for the Paris deal since it was signed in 2015.
• Trump is also likely to formally withdraw from Paris climate accords the day after the election.

Go deeper: Axios' special report on climate change

One CES highlight: Quibi, the mobile video app being launched in April by Jeffrey Katzenberg and Meg Whitman, debuted a new mobile video technique to differentiate from other mobile video experiences like Snapchat or Instagram, Axios' Sara Fischer reports.

• Turnstyle stitches together two videos of the same scene, one captured in a landscape lens (horizontally) and one captured in a portrait lens (vertically).
• More CES news.

1. More Senate Democrats want House Speaker Pelosi to send over the articles of impeachment. Go deeper.
2. Twitter plans to roll out the ability for users to limit who can reply to their tweets with four new options. Go deeper.
3. The U.S. cancer death rate dropped 2.2% between 2016 and 2017, the largest decline recorded in national cancer statistics dating back to 1930. Go deeper.
4. Supreme Court Justice Ruth Bader Ginsburg told CNN she is starting the year "cancer free," after suffering from a series of health complications in recent years.
5. DNC chair Tom Perez is launching a tour of battleground states to raise concerns about President Trump's approach to health care. Go deeper.

Drama in the U.K.: Buckingham Palace is reportedly "disappointed" with Prince Harry and Meghan Markle's decision to step away from the family, BBC reports.

• Why it matters: The move can be viewed as an effective resignation from royal duties by the pair — after they faced increasing harassment from the press.

Between the lines: 2019 was a brutal year for the royal family, as Prince Andrew faced blowback over his ties to Jeffrey Epstein.

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