Pierre Friedlingstein
@pfriedling.bsky.social
Born at 321 ppm. Climate & Carbon Cycle Scientist. Prof @UniofExeter Directeur de Recherche @CNRS @GlobalCarbonProject
November 13, 2025 at 6:37 PM
November 13, 2025 at 6:37 PM
November 13, 2025 at 6:37 PM
Keeping warming well below 2°C is still within reach, but with massive acceleration of emission mitigation.
It’s time to step up, not to give up.
It’s time to step up, not to give up.
November 13, 2025 at 6:37 PM
Keeping warming well below 2°C is still within reach, but with massive acceleration of emission mitigation.
It’s time to step up, not to give up.
It’s time to step up, not to give up.
Time is up for 1.5°C. The remaining carbon budget for 1.5°C is virtually exhausted: 170 GtCO2, equivalent to 4 years at the 2025 emissions levels.
November 13, 2025 at 6:37 PM
Time is up for 1.5°C. The remaining carbon budget for 1.5°C is virtually exhausted: 170 GtCO2, equivalent to 4 years at the 2025 emissions levels.
Since 1960, that climate impact leads to a loss of carbon from land and ocean (relative to what they would have been without climate change). We attribute that 8ppm (8%) of the observed atmospheric CO₂ increase of 100 ppm since 1960 is due to this weakening of the sinks.
November 13, 2025 at 6:37 PM
Since 1960, that climate impact leads to a loss of carbon from land and ocean (relative to what they would have been without climate change). We attribute that 8ppm (8%) of the observed atmospheric CO₂ increase of 100 ppm since 1960 is due to this weakening of the sinks.
We also analysed the effect of climate change on the sinks using our models separating the effect of increased atmospheric CO₂, from the effect of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
November 13, 2025 at 6:37 PM
We also analysed the effect of climate change on the sinks using our models separating the effect of increased atmospheric CO₂, from the effect of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
and land sink to return to a stronger “neutral” state.
So the so called “collapse” of the land sink was a short term response to climate anomalies, not a long term response.
So the so called “collapse” of the land sink was a short term response to climate anomalies, not a long term response.
November 13, 2025 at 6:37 PM
and land sink to return to a stronger “neutral” state.
So the so called “collapse” of the land sink was a short term response to climate anomalies, not a long term response.
So the so called “collapse” of the land sink was a short term response to climate anomalies, not a long term response.
However, we expect the opposite for 2025 (red dots): atmospheric CO₂ growth rate to return to a lower value
November 13, 2025 at 6:37 PM
However, we expect the opposite for 2025 (red dots): atmospheric CO₂ growth rate to return to a lower value
2023-2024 El Niño led to a record high atmospheric CO₂ increase of 29 GtCO2 in 2024 (3.7 ppm), almost 50% above the decadal average.
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
November 13, 2025 at 6:37 PM
2023-2024 El Niño led to a record high atmospheric CO₂ increase of 29 GtCO2 in 2024 (3.7 ppm), almost 50% above the decadal average.
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
And over the last 150 years
November 13, 2025 at 6:22 PM
And over the last 150 years
Altogether, here is the whole budget over the last decade
November 13, 2025 at 6:22 PM
Altogether, here is the whole budget over the last decade
I believe they tried to show the effect of climate change on the land sink, ocean sink and atmospheric CO₂ from our Nature paper published yesterday :
November 13, 2025 at 3:15 PM
I believe they tried to show the effect of climate change on the land sink, ocean sink and atmospheric CO₂ from our Nature paper published yesterday :
Keeping warming well below 2°C is still within reach, but with massive acceleration of emission mitigation.
It’s time to step, not to give up.
It’s time to step, not to give up.
November 13, 2025 at 3:07 PM
Keeping warming well below 2°C is still within reach, but with massive acceleration of emission mitigation.
It’s time to step, not to give up.
It’s time to step, not to give up.
Time is up for 1.5°C. The remaining carbon budget for 1.5°C is virtually exhausted: 170 GtCO2, equivalent to 4 years at the 2025 emissions levels.
November 13, 2025 at 3:07 PM
Time is up for 1.5°C. The remaining carbon budget for 1.5°C is virtually exhausted: 170 GtCO2, equivalent to 4 years at the 2025 emissions levels.
Since 1960, that climate impact leads to a loss of carbon from land and ocean (relative to what they would have been without climate change). We attribute that 8ppm (8%) of the observed atmospheric CO₂ increase of 100 ppm since 1960 is due to this weakening of the sinks.
November 13, 2025 at 3:07 PM
Since 1960, that climate impact leads to a loss of carbon from land and ocean (relative to what they would have been without climate change). We attribute that 8ppm (8%) of the observed atmospheric CO₂ increase of 100 ppm since 1960 is due to this weakening of the sinks.
We also analysed the effect of climate change on the sinks using our models separating the effect of increased atmospheric CO₂, from the effect of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
November 13, 2025 at 3:07 PM
We also analysed the effect of climate change on the sinks using our models separating the effect of increased atmospheric CO₂, from the effect of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
Result: The land and ocean sinks would have been 25% and 7% larger in the absence of climate change.
2023-2024 El Niño led to a record high atmospheric CO₂ increase of 29 GtCO2 in 2024 (3.7 ppm), almost 50% above the decadal average.
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
November 13, 2025 at 3:07 PM
2023-2024 El Niño led to a record high atmospheric CO₂ increase of 29 GtCO2 in 2024 (3.7 ppm), almost 50% above the decadal average.
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
The land sink decreased substantially, 20% below the decadal average, 40% below 2022 (pre-El Niño). The tropics recorded the largest drop in the land C sink
That’s quite different from previous GCB reports where the land sink was slightly larger than the ocean sink.
November 13, 2025 at 3:07 PM
That’s quite different from previous GCB reports where the land sink was slightly larger than the ocean sink.
Land ecosystems and the ocean are responsible for absorbing the other 50% of anthropogenic emissions. Land sink account for about 21% (8.7 GtCO2/yr, average over last decade). Ocean sink accounts for 29% (8.7 GtCO2/yr).
November 13, 2025 at 3:07 PM
Land ecosystems and the ocean are responsible for absorbing the other 50% of anthropogenic emissions. Land sink account for about 21% (8.7 GtCO2/yr, average over last decade). Ocean sink accounts for 29% (8.7 GtCO2/yr).
The annual growth rate of CO₂ in the atmosphere is still increasing. Average over the last decade was 20.4 GtCO2 per year (that’s 2.6 ppm increase per year).
Lots of year to year variability with much larger growth rate in 2024, but much lower expected in 2025. I’ll come back to that.
Lots of year to year variability with much larger growth rate in 2024, but much lower expected in 2025. I’ll come back to that.
November 13, 2025 at 3:07 PM
The annual growth rate of CO₂ in the atmosphere is still increasing. Average over the last decade was 20.4 GtCO2 per year (that’s 2.6 ppm increase per year).
Lots of year to year variability with much larger growth rate in 2024, but much lower expected in 2025. I’ll come back to that.
Lots of year to year variability with much larger growth rate in 2024, but much lower expected in 2025. I’ll come back to that.