Leon Simons
@leonsimons.bsky.social
Mission: To understand & protect the home planet.
Innovator, climate research & communication, social entrepreneur.
Board member Club of Rome NL
Innovator, climate research & communication, social entrepreneur.
Board member Club of Rome NL
The RATE of CO₂ increase keeps increasing.
It's not exponential (like the @clubofrome.org 1972 'Limit's to growth' projection), but there is little indication of the growth rate stabilizing (let alone decreasing) any time soon either.
It's not exponential (like the @clubofrome.org 1972 'Limit's to growth' projection), but there is little indication of the growth rate stabilizing (let alone decreasing) any time soon either.
November 15, 2025 at 12:18 PM
The RATE of CO₂ increase keeps increasing.
It's not exponential (like the @clubofrome.org 1972 'Limit's to growth' projection), but there is little indication of the growth rate stabilizing (let alone decreasing) any time soon either.
It's not exponential (like the @clubofrome.org 1972 'Limit's to growth' projection), but there is little indication of the growth rate stabilizing (let alone decreasing) any time soon either.
Last year's estimate for 2024 was off by a mile, so I don't put much trust in the 2025 estimate:
November 14, 2025 at 10:54 PM
Last year's estimate for 2024 was off by a mile, so I don't put much trust in the 2025 estimate:
I'm a bit hesitant about making absolute statements about a year that hasn't ended yet.
Especially considering conflicting signals and past rectifications.
Especially considering conflicting signals and past rectifications.
November 14, 2025 at 10:15 PM
I'm a bit hesitant about making absolute statements about a year that hasn't ended yet.
Especially considering conflicting signals and past rectifications.
Especially considering conflicting signals and past rectifications.
Greenhouse gases we add to the atmosphere and the resulting Earth's Energy Imbalance could cause about a yottajoule (1,000,000,000,000,000,000,000,000 joules) of heat to accumulate in the Earth system this century.
Causing an energy level similar to the Eemian, when sea level was ~7.5m higher!
1/
Causing an energy level similar to the Eemian, when sea level was ~7.5m higher!
1/
November 14, 2025 at 9:54 PM
Greenhouse gases we add to the atmosphere and the resulting Earth's Energy Imbalance could cause about a yottajoule (1,000,000,000,000,000,000,000,000 joules) of heat to accumulate in the Earth system this century.
Causing an energy level similar to the Eemian, when sea level was ~7.5m higher!
1/
Causing an energy level similar to the Eemian, when sea level was ~7.5m higher!
1/
The atmospheric CO₂ growth rate was off the chart in 2024!
November 14, 2025 at 7:00 PM
The atmospheric CO₂ growth rate was off the chart in 2024!
29 Gt is off the chart indeed
November 14, 2025 at 6:41 PM
29 Gt is off the chart indeed
Looks like your atmospheric growth rate graph in GtCO₂/yr needs a y-axis extension?
November 14, 2025 at 6:24 PM
Looks like your atmospheric growth rate graph in GtCO₂/yr needs a y-axis extension?
Journalists around the world keep misrepresenting scientific research on climate change.
Polical reports on false progress don't help.
We could experience monthly temperatures of +2.6°C above pre-industrial during an El Niño in about a decade
And there's a substantial risk of passing +3°C by 2050
Polical reports on false progress don't help.
We could experience monthly temperatures of +2.6°C above pre-industrial during an El Niño in about a decade
And there's a substantial risk of passing +3°C by 2050
November 14, 2025 at 3:42 PM
Journalists around the world keep misrepresenting scientific research on climate change.
Polical reports on false progress don't help.
We could experience monthly temperatures of +2.6°C above pre-industrial during an El Niño in about a decade
And there's a substantial risk of passing +3°C by 2050
Polical reports on false progress don't help.
We could experience monthly temperatures of +2.6°C above pre-industrial during an El Niño in about a decade
And there's a substantial risk of passing +3°C by 2050
En Hansen wordt niet juist geciteerd.
In onze 'Global warming in the pipeline' studie beschreven we een verwachte versnelling naar 0.27-36°C/decennium vanaf 2010.
De snelheid van opwarming ligt nu mogelijk al hoger.
Hier nog wat relevante grafieken.
@trouw.nl
In onze 'Global warming in the pipeline' studie beschreven we een verwachte versnelling naar 0.27-36°C/decennium vanaf 2010.
De snelheid van opwarming ligt nu mogelijk al hoger.
Hier nog wat relevante grafieken.
@trouw.nl
November 14, 2025 at 2:01 PM
En Hansen wordt niet juist geciteerd.
In onze 'Global warming in the pipeline' studie beschreven we een verwachte versnelling naar 0.27-36°C/decennium vanaf 2010.
De snelheid van opwarming ligt nu mogelijk al hoger.
Hier nog wat relevante grafieken.
@trouw.nl
In onze 'Global warming in the pipeline' studie beschreven we een verwachte versnelling naar 0.27-36°C/decennium vanaf 2010.
De snelheid van opwarming ligt nu mogelijk al hoger.
Hier nog wat relevante grafieken.
@trouw.nl
Pro-tip for journalists:
Whether it's UNEP, Bill Gates or anyone else making these statements, ask them for their math.
The future non-CO₂ greenhouse gas- and aerosols forcings (that what forces the climate to change) are 'Not Available'...
And climate sensitivity is higher than assumed.
Whether it's UNEP, Bill Gates or anyone else making these statements, ask them for their math.
The future non-CO₂ greenhouse gas- and aerosols forcings (that what forces the climate to change) are 'Not Available'...
And climate sensitivity is higher than assumed.
November 13, 2025 at 2:48 PM
Pro-tip for journalists:
Whether it's UNEP, Bill Gates or anyone else making these statements, ask them for their math.
The future non-CO₂ greenhouse gas- and aerosols forcings (that what forces the climate to change) are 'Not Available'...
And climate sensitivity is higher than assumed.
Whether it's UNEP, Bill Gates or anyone else making these statements, ask them for their math.
The future non-CO₂ greenhouse gas- and aerosols forcings (that what forces the climate to change) are 'Not Available'...
And climate sensitivity is higher than assumed.
Will Libera even be launched?
'Due to the lapse in federal government funding, NASA is not updating this website.'
science.nasa.gov/mission/libe...
'Due to the lapse in federal government funding, NASA is not updating this website.'
science.nasa.gov/mission/libe...
November 13, 2025 at 1:03 AM
Will Libera even be launched?
'Due to the lapse in federal government funding, NASA is not updating this website.'
science.nasa.gov/mission/libe...
'Due to the lapse in federal government funding, NASA is not updating this website.'
science.nasa.gov/mission/libe...
'CERES is the only project worldwide whose prime objective is to produce global climate data records of Earth’s radiation budget (ERB) from instruments designed to observe the ERB'
November 13, 2025 at 1:00 AM
'CERES is the only project worldwide whose prime objective is to produce global climate data records of Earth’s radiation budget (ERB) from instruments designed to observe the ERB'
November 12, 2025 at 8:29 AM
The past 3-years were on average +1.5°C, while the Relative Oceanic Niño Index was on average -0.19.
The Paris agreement is dead and buried.
What impact will this have on the negotiations in Belém at COP30?
The Paris agreement is dead and buried.
What impact will this have on the negotiations in Belém at COP30?
November 11, 2025 at 12:08 AM
The past 3-years were on average +1.5°C, while the Relative Oceanic Niño Index was on average -0.19.
The Paris agreement is dead and buried.
What impact will this have on the negotiations in Belém at COP30?
The Paris agreement is dead and buried.
What impact will this have on the negotiations in Belém at COP30?
If @drjamesehansen.bsky.social at all. (2025, mainly based on NASA CERES observations) is correct about the very strong shipping SOx forcing, the climate is more sensitive to anthropogenic forcings (incl both GHGs and aerosols).
Which e.g. means we need much faster mitigation and adaptation.
Which e.g. means we need much faster mitigation and adaptation.
November 10, 2025 at 3:14 PM
If @drjamesehansen.bsky.social at all. (2025, mainly based on NASA CERES observations) is correct about the very strong shipping SOx forcing, the climate is more sensitive to anthropogenic forcings (incl both GHGs and aerosols).
Which e.g. means we need much faster mitigation and adaptation.
Which e.g. means we need much faster mitigation and adaptation.
Many use the word exponential without knowing what it actually means.
One thing that does increase exponentially is the amount of water the air can hold with every degree Celsius (+7%) of temperature increase.
This leads to both more (extreme) evaporation and precipitation.
One thing that does increase exponentially is the amount of water the air can hold with every degree Celsius (+7%) of temperature increase.
This leads to both more (extreme) evaporation and precipitation.
November 10, 2025 at 2:07 AM
Many use the word exponential without knowing what it actually means.
One thing that does increase exponentially is the amount of water the air can hold with every degree Celsius (+7%) of temperature increase.
This leads to both more (extreme) evaporation and precipitation.
One thing that does increase exponentially is the amount of water the air can hold with every degree Celsius (+7%) of temperature increase.
This leads to both more (extreme) evaporation and precipitation.
😔
"even the lower end of the predicted range for 2025 would result in a 3-year average above 1.5°C, according to the ERA5 dataset. This would be the first time that this has occurred in the instrumental period."
@ecmwf.int
@copernicusecmwf.bsky.social
"even the lower end of the predicted range for 2025 would result in a 3-year average above 1.5°C, according to the ERA5 dataset. This would be the first time that this has occurred in the instrumental period."
@ecmwf.int
@copernicusecmwf.bsky.social
November 8, 2025 at 11:41 PM
😔
"even the lower end of the predicted range for 2025 would result in a 3-year average above 1.5°C, according to the ERA5 dataset. This would be the first time that this has occurred in the instrumental period."
@ecmwf.int
@copernicusecmwf.bsky.social
"even the lower end of the predicted range for 2025 would result in a 3-year average above 1.5°C, according to the ERA5 dataset. This would be the first time that this has occurred in the instrumental period."
@ecmwf.int
@copernicusecmwf.bsky.social
Same graph for the tropics.
Make your own here (I plotted @ecmwf.int ERA5 Sea Surface Temperatures for November-October here):
climatereanalyzer.org/research_too...
Make your own here (I plotted @ecmwf.int ERA5 Sea Surface Temperatures for November-October here):
climatereanalyzer.org/research_too...
November 8, 2025 at 11:12 PM
Same graph for the tropics.
Make your own here (I plotted @ecmwf.int ERA5 Sea Surface Temperatures for November-October here):
climatereanalyzer.org/research_too...
Make your own here (I plotted @ecmwf.int ERA5 Sea Surface Temperatures for November-October here):
climatereanalyzer.org/research_too...
Ignoring the tropics because of El Niño/La Niña, the past 12 months show record Sea Surface Temperatures for both hemispheres.
And the acceleration of warming over the Northern Hemisphere is painfully obvious:
And the acceleration of warming over the Northern Hemisphere is painfully obvious:
November 8, 2025 at 11:04 PM
Ignoring the tropics because of El Niño/La Niña, the past 12 months show record Sea Surface Temperatures for both hemispheres.
And the acceleration of warming over the Northern Hemisphere is painfully obvious:
And the acceleration of warming over the Northern Hemisphere is painfully obvious:
'Man who jumped out of an airplane without parachute and who has already hit the ground will overshoot goal not to die, UN said'
November 8, 2025 at 3:56 PM
'Man who jumped out of an airplane without parachute and who has already hit the ground will overshoot goal not to die, UN said'
Has anyone already pointed out that the Northern Hemisphere mid latitude oceans are cooling? 🤦♂️
November 8, 2025 at 3:39 PM
Has anyone already pointed out that the Northern Hemisphere mid latitude oceans are cooling? 🤦♂️
If our years ran from November to October, 2025 would be the second warmest year on record.
Probably in >100,000 years and potentially much longer.
Sea Surface Temperatures are now likely already higher than during the Eemian warm period, when global sea levels were ~7.5m higher!
Probably in >100,000 years and potentially much longer.
Sea Surface Temperatures are now likely already higher than during the Eemian warm period, when global sea levels were ~7.5m higher!
November 8, 2025 at 3:34 PM
If our years ran from November to October, 2025 would be the second warmest year on record.
Probably in >100,000 years and potentially much longer.
Sea Surface Temperatures are now likely already higher than during the Eemian warm period, when global sea levels were ~7.5m higher!
Probably in >100,000 years and potentially much longer.
Sea Surface Temperatures are now likely already higher than during the Eemian warm period, when global sea levels were ~7.5m higher!
This Dutch solar boom has led to negative electricity prices during most sunny summer days.
The grid can't cope and it's nearly impossible to get a new grid connection in most parts of the country.
The grid can't cope and it's nearly impossible to get a new grid connection in most parts of the country.
November 8, 2025 at 11:36 AM
This Dutch solar boom has led to negative electricity prices during most sunny summer days.
The grid can't cope and it's nearly impossible to get a new grid connection in most parts of the country.
The grid can't cope and it's nearly impossible to get a new grid connection in most parts of the country.
The fact that the Netherlands (18 million inhabitants, ~at 52°N) has more solar installed than all of Africa (1,561 million inhabitants, entirely in the sunbelt) is a gross failure of humanity.
November 8, 2025 at 11:31 AM
The fact that the Netherlands (18 million inhabitants, ~at 52°N) has more solar installed than all of Africa (1,561 million inhabitants, entirely in the sunbelt) is a gross failure of humanity.