JMA: October25 was 3rd-warmest Oct.

The Japan Meteorological Agency says October was the third-warmest October in their records, which start in 1891.

2025 is almost certainly going to be the third-warmest year in their record, after 2024 (anomaly = 0.63°C relative to the 1991-2020 average) and 2023 (0.54°C). Through Oct25 this year is 0.48°C. 

Their 30-year trend is +0.22°C/decade. 20-year trend is +0.29°C/decade (that's 1.0°F in just 20 years).

Their total warming = 1.06°C since 1891. (1.91°F.)

Now that the US government is (unfortunately) open again, we might get numbers from NOAA and NASA soon.

You Lost, You Lost, You're Next

The Bugs Are Coming

I saw two articles in the last few days about bugs appearing where they have never been before, due to, at least in part, climate change:

• a women who says she hasn't recently been off Long Island in the US somehow acquired the viral disease chikungunya (NY Times, free article), "the first such case of local transmission ever recorded in New York."
• it's been confirmed that a mosquito has been in Iceland, the first.

Of course these could be one-offs. But it's the kind of thing scientists have talked about for decades. We'll see....

PS: Yes I used the word "bug" to describe a virus. Colloquial usage.

Chinese vs US Wind

Paul Krugman: "In his rambling speech at the United Nations, Donald Trump insisted that China isn’t making use of wind power: 'They use coal, they use gas, they use almost anything, but they don’t like wind.' I don’t know where Trump gets his misinformation — maybe the same sources telling him that Portland is in flames. But here’s the reality:" (link)

Krugman also gives this chart, regarding the US:

Grok says the average US home uses 1,232 watts of electricity, so the above projection change of about 40 GW is enough electricity for over 32 million homes! That's about 24% (!!) of Grok's estimated 134.3 M occupied households in the US in 2030. 

One-quarter of US homes.

I didn't realize Trump was fowling things up THIS badly....

Shelley's "The Cloud"

From the dedication page of Atmospheric Science: An Introductory Survey, 2nd edition (2006) by Wallace and Hobbs, dedicated to co-author Peter V. Hobbs.

2025 Will Likely be Third-Warmest Year

The last three years of monthly temperatures, via Copernicus. 

This year should easily be the third-warmest year in their record (which goes back to 1940; not sure how they got their 1850-1900 baseline). But probably no higher, even though this September saw a significant increase from August. 

The 2025 year-to-date average is 1.46°C relative to 1850-1900, so just below 1.5°C. September was 1.47°C. If the last three months of the year average 1.613̅ °C higher, the yearly average will be above 1.5°C. (That quasi-bar above the 3 means it's a repeating number ad infinitum; the exact number is 121/75.)

For comparison, 2023 averaged 1.48°C and 2024 averaged 1.60°C. Another year above 1.5°C would definitely be newsworthy, especially as 2025 has basically been ENSO-neutral. And then it would be the second-warmest year.  

PS: GISS and NOAA won't be updating their monthly numbers due to the US government shutdown. Not sure if they will even be allowed after Trump's anti-climate change orders. Same for PIOMAS Arctic sea ice volume. NSIDC sea ice extent & area numbers did arrive for September shortly after October started.

the UK (for now)

Antarctica Sea Ice Width is Decreasing

Of course it is. I recently heard that it had drawn 100 km closer to shore. Maybe it was 80 km. I thought I'd try to estimate that.

I'll assume Antarctica is a perfect circle, as well as the sea ice. So the sea ice is an annulus with width w, the distance between its outer and inner radii. Then it's real easy to calculate w of the sea ice from its area (not extent), 13.72 Mkm², and the average radius (R) of Antarctica, =sqrt(A_ant/pi):

where "si" is sea ice. Using average annual area, this gives the following graph:

I spent a lot of time trying to make a pretty graph on datawrapper.de, but it was too complicated to get exactly what I want. So this will have to do.

In 2023 it looked like the average width had shrunk by about 75 km, but by 2024, while perhaps an anomaly, reduced that to 50-60 km. Still good enough for approximate work.

HadCET At a Record

Just a short note: the year-to-date HadCET average monthly temperature (Hadley Central England Temperature (data)), is at a record high through September, tied with 2022. 

There's also a tie for second third place, between 2023 and 2024.  

In other words, the four warmest HadCET year-to-date averages, through Septembers, have been the last four years.

The record is now 367 years long.

That's really quite remarkable.

PS: The 50-year linear trend of HadCET is 0.32°C/decade. Also, the 10-year moving average is at a record high.

Jonathan Pie Works Through the Debris

This Is Fascism

Fascism: Words to be avoided or limited in government documents according to the Trump administration: female, females women victim, victims pollution climate science injustice bias, racism, trauma race, gender status (huh?) disability, disabilities plus many more. www.nytimes.com/interactive/...

— David Appell (@davidappell.bsky.social) September 26, 2025 at 4:27 PM

Obvious Vaccine Question

I was wondering, given our idiotic Secretary of Health and Human Services (RFK Jr) and clownish president, who think vaccines and acetaminophen cause autism...What is the percentage of unvaccinated children who develop autism? 

It's an obvious question but I've never see Sec HHS ask it. Or provide research on it. They can just look at the MMR vaccine if they want, as they mistakenly believe it causes autism.... By now the US has a large enough cohort of unvaccinated children (7.5% according to Grok) to make such a study possible. 

====================

Or I could ask Grok:

For example, a 2019 Danish study of over 650,000 children found no difference in autism rates between vaccinated and unvaccinated groups.

I wish some reporter with press access to RFKJr and Trump would ask them this question. But from what I can tell they never ask hard questions. Seems they usually ask only about Gaza and Ukraine.

Ask Trump if he believes CO2 absorbs infrared radiation. Please....

====================

PS: Here's that Danish study.

China versus US Emissions

Inspired by this article in the NY Times (free link) titled "China Is the Adult in the Room on Climate Now," and this comment complaining that China burns more coal than the rest of the world combined, I did a little calculating. 

From ChatGPT and Grok I obtained this data:

So yes, China's per capita coal consumption is 3.5 t to the US's 1.0 t. 

But China's per capita CO2e emissions for 2024 were 11.2 t CO2e compared to the US's 15.7 t CO2e.

So it's hard to complain. Yes, China emits 3.0 times more CO2e than the US, but they have a much larger population. They're a much older country. When the US has been around 4,000 years it too could well have a population of 1.4 billion people.

Of course the US won't be around in 4,000 years. It might not be here next Wednesday. But if anyone can make it another 4,000 years it's probably China.

If, today, the US had China's population it would emit 22.1 Gt CO2e. That's 6.3 Gt CO2e more than China emits now. That's 118% of US emissions. 

118%. 

Naturally the planet doesn't care about our silly national boundaries, but the fact is the climate would be better off if the US emitted like China and not like it does now. 

If the US emitted like China its emissions would be 3.8 Gt CO2e, 29% lower than they are. Globally emissions would be roughly 4% lower. 

{I thought that last number would be bigger. CC really is a wicked problem.}