The NOAA Annual Greenhouse Gas Index is an index and not meant represent all forcings and feedbacks. The total (IPCC methodology based) greenhouse gas forcing in 2024 was about 4.1 W/m², or 573 ppm. See forcings and feedback estimates here:

With a treet value of ~$18,000,000,000,000

There are many indications that the global warming rate has more than doubled. It's the rate of global warming that poses such a threat.

Great visualization. Also not the procession. It seems we got relatively lucky that we increased the GHG forcing by 4.1 W/m² at the time Earth is further from the sun during the Northern Hemisphere summer.

'Biden Owes Trump $25,000,000 USD' 🤷‍♂️

One of my New Year's resolutions is to make data more accessible. Also to protect it from data purges by e.g. anthropogenic climate change-denying regimes.. Find the data uploaded to GitHub here: github.com/LeonSimons/N...

Now live!

New, high-definition Global Warming Stripes graph using NASA GISS temperature data. The 2- and 3-year averages are now +1.5°C, while the 2025 annual value was only a little bit lower, due to La Niña. Join us later today live on Climate Chat, where we look back, and forward to 2026. Link below

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It's about oil: "It's easier to imagine the end of the world than the end of [oil fuelled] capitalism" World's largest oil reserve of >300 billion barrels is now valued at ~$18,000,000,000,000. The US national debt is >2x the market value of Venezuela's oil reserve! 🤯

Sunday 1/4/26 at 10am PT on Climate Chat: 2026 Climate Change Outlook with hosts @leonsimons.com & Dan Miller. #ClimateChange #GlobalWarming #ClimateCrisis @bikingmzstacey.bsky.social @radsci.bsky.social @climatechat.bsky.social youtube.com/live/9yOfV6E...

There is a lot of evidence of the IPCC process leading to gatekeeping of inconvenient information, especially in the summaries for policymakers (which few read beyond). See for example the removal of sulphur aerosol cooling from AR6 SYR SPM: enb.iisd.org/58th-session...

I've had an appalled IPCC employee reach out to me about the gatekeeping of science by petrostate representatives. They told me that statements about '1.5°C being breached in the early 2030s in all scenarios' were scrapped from the IPCC report, during a huddle... Some scientists were crying.

Higher RCPs and SSPs likely provide the most accurate indications of climate change over the next decades. We need scenarios more in line with policy based greenhouse gas and aerosol emissions and models with paleoclimate and NASA satellite corrected climate sensitivity:

And we've ain't seen nothing yet.. Based on NASA CERES satellite observations, the amount of regional warming in the pipeline keeps increasing‼️ The level of Absorbed Solar Radiation is increasing and Outgoing Longwave Radiation can't keep up. The Pacific Decadal Oscillation is still negative:

"What we witness now, is scientific reticence on steroids. Perhaps because IPCC was granted the position of extreme authority. But in science supreme authority is not granted to anyone. Galileo proved that." @drjamesehansen.bsky.social youtu.be/4-a-qeMyaPE

There is confusion about what forces the climate to change vs what are considered feedbacks, which determine how much the climate changes from a given forcing. IPCC numbers: Well-mixed GHGs: 3.5 W/m² Other GHGs: 0.6 W/m² Total GHGs: 4.1 W/m² Aerosols: -1.1 W/m² Total: 3 W/m² 1/2

Sunday 12/28 at 10am on Climate Chat: "Climate Chat Year in Review 2025". We'll discuss the top climate stories of the year & review the 2025 Climate Chat programs. What were your favorites? @leonsimons.com @bikingmzstacey.bsky.social @radsci.bsky.social youtube.com/live/uoUNmt-... #ClimateChange

James Hansen is a great example of a 'passionately curious' scientist. James Lovelock is another, writing his last book, Novacene (with some help), at 99 years old. Both looked at other planets (Venus and Mars respectively) before they started studying Earth. bsky.app/profile/leon...

🔥 Hot take 🔥 Some stubborn old men, who find it impossible to acknowledge that they got basic numbers describing reality wrong, pose a danger to humanity.

This is perfect. The DOJ's embarrassing snafu with disappearing redactions was the fault of Elon Musk. Musk cancelled government subscriptions to Adobe programs that would have made the redactions permanent. What a pack of fools.

I highly recommend the videos on ocean currents by Jonathan Sharples, Professor of Oceanography at the University of Liverpool. Here he covers the AMOC: youtu.be/eZzpvLz4yAk

I hope everyone can enjoy this Christmas as much as our purring rooster, Tokkie:

The more you learn about ocean heat, salinity, density and currents, the more you realize how much you don't know. Luckily physics doesn't change (much) with scale and small experiments like this can help us grasp the macro scale. 1/3

This summer Ulrich Hansen and @martinwermuth.bsky.social from KliMainz visited me here in the Netherlands. They made a great visualization of the increasing Earth's Energy Imbalance. See their clear 'Don't be a fossil' explainer: youtu.be/GyAJouyOS_4

The closer we get to 2035 and 2050, the more empty promises are presented for what they were. Words are cheap, pledges about policies ten election cycles in the future are proving to be worse than useless.

This might play a role in your unhappiness:

Now available on Climate Chat, our first "Climate Chat Shorts"! on Why SRM/Solar-Geoengineering is Required. This is the presentation only without Q&A. #SRM #Geoengineering #ClimateCrisis youtu.be/lmxsr6b5IhE

Starting soon!

Most of the meaningful conversations and thoughts I've had the past 20 years were off-grid in developing countries.. There is a price to pay for constantly being 'connected' to media and the internet. We shouldn't constantly outsource deep thinking to others (and now AI...).

Based on the 11-year running mean (and on Earth's Energy Imbalance), the near-term rate of warming could turn out much higher than the linear 2010-2025 extrapolation. The next El Niño peak will be very informative for the rate of global warming, as @drjamesehansen.bsky.social points out:

Merry solstice!

Yikes

Sunday 12/21 at 10am PT on Climate Chat: Why SRM/Solar-Geoengineering is Required (with Q&A) with host Dan Miller. #SRM #ClimateCrisis youtube.com/live/icb_op9... @leonsimons.com @bikingmzstacey.bsky.social @radsci.bsky.social

More Brick-Wall-Graphs here: www.patreon.com/posts/113140...

"how can someone not at least find it interesting watching a whole planet shift geological ages in the blink of an eye?" Hear, hear!

The 30-year non-linear extrapolation now shows +3°C in 2049! I consider this unlikely but not impossible (considering Earth's Energy Imbalance has more than doubled). From a precautionary principle perspective we should plan accordingly.

The linear extrapolation of the past 15 years and the nonlinear 30-year extrapolation now both put global warming at +1.54°C above 1850-1900. Reaching +2°C in 2037 or 2034. Using the @ecmwf.int ERA5 dataset. H/t @tugberksamur.bsky.social

Your periodic reminder that the Paris Agreement didn't specify how to quantify reaching global temperature thresholds (by design, otherwise there wouldn't have been a 195-country unanimous agreement). So anyone saying that we need to wait for the 30-year average to reach +1.5°C is full of sh*t:

Climate change denial comes in many forms. As we cross the global warming level of 1.5°C with record high global CO₂ emissions, it's not physically possible to limt global warming at this level. Some seem to think that 'physically' means 'in fairyland'.

"If this shift represents an excursion into a new normal, our future could be hotter faster than expected." A year after this insightful study was published, the albedo and net flux over the Northern Hemisphere mid-latitude oceans keep decreasing: www.science.org/stoken/autho...

I'm certain we're already passed 1.5C & just waiting for the running Avg to catch up. I share @leonsimons.com view that it's patiently stupid to be looking through the rear view mirror The climate science community needs to up its game This exellent graph is from @reescreverem1.bsky.social

New handle:

Starting in one hour:

There is much more warming in the pipeline than simple models suggest. Especially regionally. Observations trump simple models. Global averaging of (outdated CMIP6) models is pretty much useless with regards to what most people care about: understanding real world impacts.

ASK US ANYTHING, before or during Climate Chat later today. What questions do you have for us? Please comment here or on YouTube: www.youtube.com/live/LZTPZOA...

Sunday 12/14 at 10am PT on Climate Chat: Ask Us Anything #2 w/ Dan Miller & @leonsimons.bsky.social. Post questions on the YouTube Live chat or post them below. On YouTube & LinkedIn. @bikingmzstacey.bsky.social @radsci.bsky.social #ClimateCrisis #ClimateAction youtube.com/live/LZTPZOA...

Heed the 'Stockdale Paradox': "You have to, on the one hand, never confuse the need for unwavering faith that you will find a way to prevail in the end. With on the other hand, the discipline to confront the most brutal facts we actually face. And we're not getting out of here by Christmas."

False hope fills me with despair. It surprised me how many of those who (should) know better have been celebrating the *false* narrative that the Paris agreement has supposedly limited warming to below 2.6°C this century. Genevieve breaks it down here:

Vanmiddag naar het ministerie van klimaat (😉) - ik kreeg een uitnodiging voor een bijeenkomst waar men stilstaat bij 10 jaar klimaatakkoord van Parijs, met sprekers als @heleendeconinck.bsky.social Benieuwd, vooral hoeveel gevoel voor urgentie ik daar ga bespeuren.