Extreme heat and drought weakened forests’ ability to absorb carbon dioxide in 2024

The amount of carbon dioxide in Earth’s atmosphere rose at record speed in 2024, likely because rainforests and other ecosystems, stressed by extreme heat and drought, absorbed far less carbon than usual.

Sarah Kaplan reports for The Washington Post.


In short:

  • Data from the National Oceanic and Atmospheric Administration (NOAA) shows atmospheric CO₂ concentrations jumped 3.75 parts per million in 2024, the largest annual increase ever recorded, exceeding the previous 2015 record by 27%.
  • Though fossil fuel emissions hit a new high, scientists say this modest rise doesn’t account for the CO₂ spike; instead, they point to stressed forests, wildfires, and prolonged droughts disrupting the planet’s natural carbon sinks.
  • A recent El Niño event, followed by persistent dryness in the Amazon and central Africa, significantly diminished the land’s ability to absorb CO₂, potentially turning vital ecosystems into net carbon sources.

Key quote:

“This tropical dryness is basically shutting down CO₂ uptake.”

— Philippe Ciais, associate director of the Climate and Environmental Sciences Laboratory

Why this matters:

For decades, Earth’s forests, grasslands, and oceans have acted like a giant sponge, soaking up nearly half the carbon dioxide emitted by human activities. But when ecosystems like the Amazon rainforest and Congo Basin become stressed — by heat, drought, or fire — their ability to store carbon falters. That means more carbon stays in the atmosphere, accelerating climate change. In 2024, the world saw signs of that shift, as extreme weather events coincided with a breakdown in CO₂ absorption. If such patterns continue, the world could enter a dangerous feedback loop: warming damages ecosystems, which then release more carbon, which in turn speeds up warming. This would make it harder to predict or control climate outcomes, putting human health, food systems, and biodiversity at greater risk.

Read more: Forests struggle to absorb carbon due to extreme heat and wildfires

A view of turquoise water and a tropical island

‘We didn’t lose each other:’ How people are picking up the pieces after Super Typhoon Sinlaku

Residents of the Northern Mariana Islands are no strangers to tropical cyclones, but climate change is supercharging storms and disrupting education on the islands.

Rows of US dollars on a red background

Trump’s Iran war may stymie climate gains with boost to big oil, experts say

Windfall profits could lock in Trump-era political wins for the fossil fuel industry and slow clean-energy transition.

A dam allowing water to flow

Close calls at Michigan's dams are a climate warning to America

Record flooding pushed Michigan's dams to the brink of disaster and showed just how unprepared U.S. infrastructure is for a warming world.

A view of a woman's hands with a fishing pole
Credit: A.C./Unsplash+

As summer fishing heats up, so do worries about fish health

It’s only early May, and Wyoming's fisheries biologists are already prepping anglers for a summer of low, hot flows, sluggish fish, and the possibility that some waters will dry up completely.

A farmer crouching in a dry field with a harvester in the background

Environmental economist explains how climate change is pushing agricultural systems to the brink

Extreme temperature swings are disrupting crops and endangering agricultural workers; we spoke with environmental economist Shouro Dasgupta about farming in an overheating world.

A view of a flooded barn

Enviros say Supreme Court decision boosts states' ‘climate superfunds’

The Trump administration is suing Vermont and New York for using novel tactics to curb greenhouse gas emissions.
From our Newsroom
Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

One facility has emitted cancer-causing chemicals into waterways at levels up to 520% higher than legal limits.

Regulators are underestimating health impacts from air pollution: Study

Regulators are underestimating health impacts from air pollution: Study

"The reality is, we are not exposed to one chemical at a time.”

Pennsylvania governor Josh Shapiro speaks with the state flag and American flag behind him.

Two years into his term, has Gov. Shapiro kept his promises to regulate Pennsylvania’s fracking industry?

A new report assesses the administration’s progress and makes new recommendations

silhouette of people holding hands by a lake at sunset

An open letter from EPA staff to the American public

“We cannot stand by and allow this to happen. We need to hold this administration accountable.”

wildfire retardants being sprayed by plane

New evidence links heavy metal pollution with wildfire retardants

“The chemical black box” that blankets wildfire-impacted areas is increasingly under scrutiny.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.