William F. Lamb

Expertise from the Potsdam Institute.

8 Lead Authors for @IPCC_CH #AR7:

nico bauer
Niklas Boers
Franziska Piontek
Iulii Didovets
Barbora Sedova
@wflamb.bsky.social
Jan Minx
Elmar Kriegler

First Lead Author meeting Dec 2025, report out 2028/29.

www.pik-potsdam.de/en/news/late...

bar chart showing deaths associate with extreme heat with and without climate change in 12 European cities

About 1500 of the approx. 2300 people that will have lost their lives across 12 European cities last week would still live, if it wasn't for our burning of oil, coal and gas. If we care about the right to life, we need to stop burning fossil fuels. www.imperial.ac.uk/grantham/pub...

Out today: Freedom for Capital not People: The Mont Pèlerin Society and the Origins of the Neoliberal Monetary Order @versobooks.bsky.social

Höhepunkt der CO2-Emissionen noch nicht erreicht Während Delegierte aus aller Welt in Bonn die nächste Klimakonferenz vorbereiten, offenbart ein neuer Bericht die fragile Lage des Weltklimas. Die Forderungen nach einem Umsteuern werden immer lauter....

Höhepunkt der Emissionen noch nicht erreicht - Tagesschau Online berichtet über Report „Indikatoren des globalen Klimawandels“. Es werde immer schwieriger, die 1,5 Grad noch zu halten, je länger Emissionen nicht reduziert würden, so PIK Forscher @wflamb.bsky.social
www.tagesschau.de/wissen/klima...

😆oops

And Thailand

Some impressively complete data from Nepal in the latest version

Just did a small update of Tidy GHG Inventories: lambwf.github.io/Tidy-GHG-Inv...

81 countries have now submitted inventory data with their Biennial Transparency Reports. Quite a few still haven't (its 6 months past the deadline btw).

Having said that, including LULUCF in total emissions only changes the recent trend in a few isolated cases (top left, bottom right).

But we can probably expect to see more European countries enter the "slower reductions" zone as natural disturbances cut into the land sink.

A dot plot comparing the change in national GHG emissions over the past 5 years with (x axis) and without (y axis) the LULUCF sector

The land use change (LULUCF) sector is pretty confusing, since it can be a source of emissions (deforestation, disturbances) as well as a source of removals (regrowth, management).

Including LULUCF can speed up, slow down, or change the overall dynamic of economy-wide emissions.

Quite possibly the biggest climate story of the year (especially when we look back on this in a few years' time)

For the first time on record, China's emissions are falling due to clean energy growth, not slow power demand...

Will Lamb @wflamb.bsky.social has pulled the troops together & submitted an article to explain why different datasets can give different estimates of GHG emissions.

My favourite: differences in accounting for fire emissions.

Article in review, please comment!

essd.copernicus.org/preprints/es...

Differences in anthropogenic greenhouse gas emissions estimates explained Abstract. We examine differences in global and national greenhouse gas (GHG) emissions estimates and highlight the important role of varying system boundaries and conceptual approaches in driving thes...

New preprint: differences in anthropogenic greenhouse gas emissions explained essd.copernicus.org/preprints/es...

Greenhouse gas emissions are still mostly from fossil fuels by the way!!

lambwf.github.io/UNEP-Gap-Rep...

The EU has released its latest GHG emission inventory, with data up to 2023.

The good news, GHG emissions continue a downward trend, currently 37% below 1990 levels.

The bad news, a significant downward revision of land-use removals (LULUCF).

1/

I tried

Trump’s EPA Plans to Stop Collecting Greenhouse Gas Emissions Data From Most Polluters Climate experts expressed shock and dismay at the move. “It would be a bit like unplugging the equipment that monitors the vital signs of a patient that is critically ill,” one said.

So the US was supposed to report its greenhouse gas emissions to the UNFCCC yesterday.

For the first time since 1997, it didn't.

This follows last week's revelation that Trump's EPA is stopping collection of GHG emission from 40 of 41 sectors

www.propublica.org/article/trum...

I find these quite useful for explaining trends, but it seems to me there is a lot going on behind the scenes in counterfactual estimates. I'd like to see more literature on it, in case anyone has some leads...

And here one on energy demand from @ember-energy.org

ember-energy.org/latest-insig...

Interesting that people are starting to incorporate these counterfactuals in their emissions reporting. Here's a similar take from the @iea.org

www.iea.org/reports/glob...

Global carbon emissions and decarbonization in 2024 - Nature Reviews Earth & Environment Global CO2 emissions in 2024 increased 0.9% on the previous year, totalling 36.3 Gt CO2. These ongoing emissions further deplete remaining carbon budgets, with some estimates suggesting the 1.5 °C bud...

According to Carbon Monitor, emissions could have been 9.8GtCO2 higher in 2024... if renewable energy supply had been met with expected fossil sources instead

www.nature.com/articles/s43...

Lots more figures here: lambwf.github.io/Tidy-GHG-Inv...

I've updated the Tidy GHG Inventories dataset, which is now complete for Annex I countries: doi.org/10.5281/zeno...

This also shows the progress to date in countries submitting Biennial Transparency Reports under the Paris Agreement ⬇️

Prominent climate communicators continue to "joke" that what Trump is doing is "degrowth". It is not, and such claims are actively harmful. A quick🧵

You may also like:

lambwf.github.io/UNEP-Gap-Rep...
lambwf.github.io/Tidy-GHG-Inv...

If you accept that non-citizens have no right to due process, you are accepting that citizens have no right to due process. All the government has to do is claim that you are not a citizen; without due process you have no chance to prove the contrary.

😬

Sankey diagram representing fossil fuel companies and lobbyists and their nominators at COP28

This looks like a very interesting piece on interest groups at the COPs

www.nature.com/articles/s41...

Here with consumption-based CO2