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!

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!

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!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

The I-5 freeway in Los Angeles is all but empty during an initial coronavirus lockdown in April 2020. Photo: Robyn Beck/AFP via Getty Images

A recently released study finds that curtailed societal activity during the early stages of the pandemic also reduced emissions of pollutants that usually act to cool the climate.

The big picture: Coronavirus measures helped lead to a sharp, if temporary, reduction in greenhouse gases, but some other pollutants actually act to cool the climate — and with emissions of those significantly reduced as well, the climate warmed for a few months.

By the numbers: Temperatures over parts of the Earth's land in spring 2020 were about 0.2–0.5°F warmer than expected, given the prevailing weather at the time, according to a study by scientists at the National Center for Atmospheric Research.

  • The effect was particularly pronounced in areas that usually have a lot of aerosol pollution, like the U.S., where temperatures were up 0.7°F above expected levels in much of the country.

Flashback: Some of the defining images of the early months of the pandemic included the sudden appearance of clear skies in usually smog-choked cities like Los Angeles and New Delhi.

  • Those pictures were a consequence of coronavirus lockdowns that sharply reduced driving and manufacturing — in other words, the activities that usually lead to pollution.

How it works: While emissions of greenhouse gases like carbon dioxide warm the climate over time because they trap heat in the atmosphere, airborne particles called aerosols released during combustion have the opposite effect, brightening clouds and reflecting heat back into space.

  • Fewer aerosols meant less of their cooling effect, which temporarily translated into a warmer Earth.

Be smart: With carbon dioxide emissions down 6.4% in 2020, the ultimate effect of the pandemic will likely be to slow global warming down slightly, as the long-term impacts of less CO2 in the air outweigh the short-term effects of fewer aerosols for a few months.

  • But the study's counterintuitive results are a reminder of climate action's time-lag problem.
  • It will take 10–20 years before we experience the cooling caused by 2020's drop in CO2 emissions, but the warming effect of reduced aerosols was experienced almost immediately, simply because the two classes of pollutants have vastly different lifespans.

The bottom line: Acting to reduce CO2 emissions now means accepting that the climate benefits will be delayed — and humans aren't great with delayed gratification.

Go deeper

Ben Geman, author of Generate
Feb 3, 2021 - Energy & Environment

Analysis: Waiting to cut emissions will ultimately make it more expensive

Adapted from an Energy Innovation report; Chart: Axios Visuals

Putting U.S. carbon emissions on a steep downward path would cost plenty of money. But waiting to act is way more expensive, a new analysis out this morning concludes.

Driving the news: The research firm Energy Innovation modeled two policy scenarios for reaching net-zero emissions by 2050, a common target for limiting the amount of future warming.

Mike Allen, author of AM
3 hours ago - Politics & Policy

Biden adviser Cedric Richmond sees first-term progress on reparations

Illustration: "Axios on HBO"

White House senior adviser Cedric Richmond told "Axios on HBO" that it's "doable" for President Biden to make first-term progress on breaking down barriers for people of color, while Congress studies reparations for slavery.

Why it matters: Biden said on the campaign trail that he supports creation of a commission to study and develop proposals for reparations — direct payments for African-Americans.

Cyber CEO: Next war will hit regular Americans online

Any future real-world conflict between the United States and an adversary like China or Russia will have direct impacts on regular Americans because of the risk of cyber attack, Kevin Mandia, CEO of cybersecurity company FireEye, tells "Axios on HBO."

What they're saying: "The next conflict where the gloves come off in cyber, the American citizen will be dragged into it, whether they want to be or not. Period."