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Rees Cat Ophuls @reescatophuls.bsky.social · 8d

Great. If I drop the rounding, then its only the leap year difference. I added the rounding to get the best match with the info that Copernicus publishes in their monthly bulletins. In particular the number of days over 2C.

Anyhow its the trend, rather than the exact numbers, that is interesting. 👍

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Rees Cat Ophuls @reescatophuls.bsky.social · 9d

Hi Eliot, what is your running total?

bsky.app/profile/rees...
Diagram below rounds to 2dp and uses days ">= 1.5C" after the rounding, so I can believe there might be a slight discrepancy.

Rees Cat Ophuls @reescatophuls.bsky.social · 18d

800 individual days have been at least 1.5C above the Pre-Industrial baseline

Summer 2025 was largely under 1.5C

> Will we pass 900 days in 2026?
> Will we pass 1000 days by 2027?
> Will the Loess 30-yr trend pass 1.5C before 2028?

Data: Copernicus ERA5 - Global Mean Surface Temperature Anomaly

Graph purpose: Show both the individual days of global warming, and the longer term trends.

X-Axis: Years, from Jan 1940 until 7th Feb 2025
Y-Axis: Cumulative number of days above different global warming milestones (Log scale, from 0 to 10,000 days). For the unwary, beware the Log Scale !!
Additional information: The Dates at which the Global Warming trend line (Loess 30 year window trend line) crossed different Global Warming Milestones. E.g. by 22nd September 2025, there have cumulatively been 800 individual days above 1.5C Global Warming.
E.g. in August 1985, the Loess trend line for the Global Mean Surface Temperature Anomaly crossed 0.5C. Note that these dates shift a bit as new data comes in. For instance, Summer 2025 a bit cooler (than 2023/2024), and this was enough to shift the date for passing 1.00C from Dec 2011 to Jan 20212 (in practice this was a shift of 3 days).

The Graphs includes Global Warming Milestones: 0.5C, 0.75C, 1C, 1.25C, 1.5C, 1.75C, 2.0C

Data used: Copernicus ERA5 with 1850-1900 baseline (Pre-Industrial)
Graph Design Details on website:
https://parisagreementtemperatureindex.com/1000-day-climate-graphic-design/
Note the log scale on the Y-Axis. This allows the graph to show that the number of days above 0.5C, 0.75C etc ... keep going up, but it allows the focus to go on the higher temperatures that are happening more recently.

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Rees Cat Ophuls @reescatophuls.bsky.social · 12d

Nice ... I wonder if the data existing to do an "anomaly" version of this.

Rees Cat Ophuls @reescatophuls.bsky.social · 18d

800 individual days have been at least 1.5C above the Pre-Industrial baseline

Summer 2025 was largely under 1.5C

> Will we pass 900 days in 2026?
> Will we pass 1000 days by 2027?
> Will the Loess 30-yr trend pass 1.5C before 2028?

Data: Copernicus ERA5 - Global Mean Surface Temperature Anomaly

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Rees Cat Ophuls @reescatophuls.bsky.social · 21d

bsky.app/profile/zack...

Zack Labe @zacklabe.com · 21d

September #Arctic sea ice thickness by decade... ❄️🥼

Data information: climatedataguide.ucar.edu/climate-data...

Four polar stereographic maps showing Arctic sea ice thickness for the month of September in 1985-1994, 1995-2004, 2005-2014, and 2015-2024. Thickness is shown with colors from black at 0 meters to purple at 2.5 meters to white at 5.0 meters. Sea ice in thinning in all regions over time.

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Reposted by Rees Cat Ophuls

Robert Rohde @rarohde.bsky.social · 24d

The Northern Pacific Ocean is currently smashing temperature records.

And it is reaching these levels far earlier than the current generation of climate models had expected.

A short thread 🧵

Time series of monthly Northern Pacific Ocean sea surface temperature anomalies from 1850 to August 2025 alongside multi-model expectations of the warming in this area (scenario SSP2-4.5).

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Rees Cat Ophuls @reescatophuls.bsky.social · Sep 12

The #Arctic Annual Sea Ice Minimum isn't what it used to be.

There is now a huge area of ice under 1.5m thick, and only tiny patches over 3.5m thick.

@polarportal.bsky.social

Image shows two images of the Arctic Sea Ice Thickness, when the Arctic Sea Ice Volume is at its annual minimum.

Image on the left is for September 12th 2005
Taken from:
https://polarportal-prod.dmi.dk/api/v1/serve-image/sea?image_name=CICE_combine_thick_SM_EN_20050912.png

Image on the right is for September 12th 2025 (E.g. 20 years later).
Taken from: https://polarportal-prod.dmi.dk/api/v1/serve-image/sea?image_name=1757683101701_CICE_combine_thick_SM_EN_20250912.png

The 2005 image on the left shows substantial areas of ice which are over 3m thick, and plenty of patches which are over 4m thick.

The 2025 image on the right shows huge areas which are below 1m thickness, and only tiny patches above 3.5m thickness.

See the main webpage, to more details:
https://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-thickness-and-volume/

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Rees Cat Ophuls @reescatophuls.bsky.social · Sep 1

Wow. That is an incredible jump. The Sea Surface Temperature Anomalies across the Pacific are quite something.
bsky.app/profile/weat...

Daniel Swain @weatherwest.bsky.social · Aug 5

There is an extreme and record-breaking (shattering?) marine heatwave currently extend across nearly entire North Pacific from Japan to only ~100 miles west of California. That anomaly not quite extend to CA coast, but has been extending farther eastward in recent days. #CAwx

Global sea surface temperature anomaly map depicting an enormous and extreme marine heatwave extending clear across the North Pacific Ocean.

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Rees Cat Ophuls @reescatophuls.bsky.social · Jul 3

To be clear "is in a dip" ... I'm referring to a very short time period. This is Presumably the expected drop during the brief la-nina followed by the enso-neutral that we're experiencing + natural variability.

The long term trends are obviously still going up.

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Rees Cat Ophuls @reescatophuls.bsky.social · Jul 3

The global average surface temperature anomaly is in a dip, with the first day below 1.1C in the last 1000 days.

Yet the regional land temperatures are pumping in record highs, day after day.

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Rees Cat Ophuls @reescatophuls.bsky.social · Jul 2

With the June data now in, the Loess-15-year trend didn't make it to 1.5C (Currently at 1.486C for ERA5 data).

Another reminder for me to stay away from any predictions (other than playing with predictions / projections made by professionals).

The loess-30-year trend currently sits at 1.422C

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Reposted by Rees Cat Ophuls

Big Bounce @bigbounce.bsky.social · Jun 21

In Berlin wird es (wenig überraschend) auch wärmer. Ich finde folgende Darstellung ganz anschaulich. Mit dem Unterschied Nordost-Deutschland vs Südfrankreich kann denke ich jeder etwas anfangen.

The graph shows that in this decade Berlin was hotter than Lyon used to be in the past (60s, 70s).

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Rees Cat Ophuls @reescatophuls.bsky.social · Jun 7

Global warming surging upwards in waves.

The last 365 days:
* 100% over 1.2C
* 67% over 1.5C
* 5% over 1.8C

Last 100 days averages below 1.5C
First day below 1.25C in 700 days
The 2024 mega surge is over.
When will the next one be?

Details in Alt Text
#ClimateChange #GlobalBoiling

X-Axis is the date 1st Jan 2000 until 5th June 2025.
Y-Axis is the percentage of the preceding 365 days, which are above different global mean surface temperature (GMST) anomaly milestones.

On 5th June 2025, the previous 365 days had:
* 100.0% days over 1.2C
* 98.6% days over 1.3C
* 86.0% days over 1.4C
* 67.4% days over 1.5C
* 42.7% days over 1.6C
* 20.0% days over 1.7C
* 4.7% days over 1.8C
* 0.8% days over 1.9C
* 0.0% days over 2.0C

The plot looks like a set of coloured waves, where each wave is a different GMST anomaly, and shows the temperatures increasing and decreasing over 5+ year periods, but overall they keep getting hotter over time.

The Global Mean Surface Temperature Anomaly values, come from Copernicus ERA5, and use the 1850-1900 "Pre-Industrial" baseline.

This graphic is an update, to the ones I posted in September 2024, February 2025, March 2025

How the graph was created:
https://parisagreementtemperatureindex.com/warming-tapestry-percent-days-over-milestone/

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Reposted by Rees Cat Ophuls

Kevin Pluck @kevpluck.bsky.social · Jun 2

Lowest global sea ice area for the date since 1979 🧪

(Just)

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Rees Cat Ophuls @reescatophuls.bsky.social · May 29

The 1000 day running average crossed 1.5C: 30 aug 2022 -> 25 May 2025 inclusive

Using virtually the same technique as @climatecasino.net for daily anomaly vs pre-industrial. Copernicus links were just for rough sanity checking.

Why "1000 days" vs "3 years"? No reason. Big round number.

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Rees Cat Ophuls @reescatophuls.bsky.social · May 29

I try to make the first part, useful alt text.
I use the additional text limit, as I am a random anonymous person on the internet, so I put additional info in the alt text to keep the main graphic clean and concise, and provide additional evidence for anyone to fact-check or reproduce the graphic.

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Rees Cat Ophuls @reescatophuls.bsky.social · May 28

1000 Day Running Average crosses 1.5C

Details in Alt Text
#ShowYourStripes @copernicusecmwf.bsky.social

Graphic: 1000-day running average Global Mean Surface Temperature (GMST) anomaly (Copernicus ERA5 data) relative to Pre-Industrial.
Graph is 1980 to May 25th 2025.
Background shows Ed Hawkin's "Show Your Stripes" lines

Source:
https://sites.ecmwf.int/data/climatepulse/data/series/era5_daily_series_2t_global.csv

How to get anomaly relative to Pre-Industrial (1850-1900):
https://parisagreementtemperatureindex.com/copernicus-1850-1900-baseline-daily-gmst/

Sanity Check Sources:
Below are links to Copernicus's website, with gives GMST anomalies for various months/years. If you average them (properly, taking into account number of days that each value represents) ... and add May 2025 values then you get a 1000-day running average crossing 1.5C on 25th May 2025
https://climate.copernicus.eu/surface-air-temperature-september-2022
September 2022 is around 1.2°C above the 1850-1900 level

https://climate.copernicus.eu/surface-air-temperature-october-2022
Oct 2022 is around 1.2°C above the 1850-1900 level

https://climate.copernicus.eu/surface-air-temperature-november-2022
Nov 2022 is around 1.2°C above the 1850-1900 level

https://climate.copernicus.eu/surface-air-temperature-december-2022
Dec 2022 is around 1.2°C above the 1850-1900 level

https://climate.copernicus.eu/copernicus-2023-hottest-year-record
2023 was 1.48°C warmer than the 1850-1900 pre-industrial level

https://climate.copernicus.eu/global-climate-highlights-2024
2024 was ... 1.60°C warmer than the pre-industrial level

https://climate.copernicus.eu/surface-air-temperature-january-2025
Jan 2025 was 1.75°C above the pre-industrial level

https://climate.copernicus.eu/surface-air-temperature-february-2025
Feb 2025 was 1.59°C above the estimated 1850-1900 average

https://climate.copernicus.eu/surface-air-temperature-march-2025
Mar 2025 was 1.60°C above the estimated 1850-1900 average

https://climate.copernicus.eu/surface-air-temperature-april-2025
Apr 2025 was 1.51°C above the estimated 1850-1900 average

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Reposted by Rees Cat Ophuls

Extreme Temperatures Around the World @extremetemps.bsky.social · May 13

ENDLESS RECORD HEAT IN INDONESIA

In more than 2 years, not a single day has passed without heat records in Indonesia.
Today Tanah Merah broke BOTH its records of May highest minimum and maximum
with 25.9/36.4

It had already broken those of all months of 2023,2024 and 2025
Crazy

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Rees Cat Ophuls @reescatophuls.bsky.social · May 9

I have July 1st pencilled in for loess-15-year trend to pass 1.5C with Copernicus era5 data.

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Rees Cat Ophuls @reescatophuls.bsky.social · May 9

Brutal temperatures forecast for Pakistan, by 15th May 2025.

Image showing a map of Asia, with an arrow pointing to Pakistan
The colours of the map indicate the forecast temperature (Celcius) for the 7-10 day forecast from ClimateReanalyzer.
Pakistan looks to be forecast 50C temperatures.
Image from: https://climatereanalyzer.org/wx/fcst_outlook/?dm_id=asia-lea2&ndays=d7-10
Taken on 9th May 2025

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Rees Cat Ophuls @reescatophuls.bsky.social · May 4

The Arctic is starting from a very thin annual max sea ice volume.
bsky.app/profile/rees...

Rees Cat Ophuls @reescatophuls.bsky.social · May 1

The #Arctic sea ice isn't what it used to be.
The area covered is similar, but now much thinner.
Details in Alt Text. @polarportal.bsky.social

Image shows two images of the Arctic Sea Ice Thickness, when the Arctic Sea Ice Volume is at its annual maximum.

Image on the left is for May 1st 2005
Taken from: https://polarportal.dk/fileadmin/polarportal/sea/CICE_combine_thick_SM_EN_20050501.png

Image on the right is for May 1st 2025 (E.g. 20 years later).
Taken from: https://polarportal.dk/fileadmin/polarportal/sea/CICE_combine_thick_SM_EN_20250501.png

The 2005 image on the left shows substantial areas of ice which are over 4m thick.

The 2025 image on the right shows huge areas which are below 2m thickness, very few areas above 4m thickness.

See the main webpage, to more details:
https://polarportal.dk/en/sea-ice-and-icebergs/sea-ice-thickness-and-volume/

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Rees Cat Ophuls @reescatophuls.bsky.social · May 1

The #Arctic sea ice isn't what it used to be.
The area covered is similar, but now much thinner.
Details in Alt Text. @polarportal.bsky.social

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Rees Cat Ophuls @reescatophuls.bsky.social · Apr 29

Nice! You can really see the shifting seasons.

The warmer colours encroaching on the colder months.

Give it another few decades, and the blue will be fully surrounded. Maybe already is, for the Arctic?

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Rees Cat Ophuls @reescatophuls.bsky.social · Apr 28

Is this jetstream blocking patterns? Heat domes etc... The global temperature still hovering around 1.5C, but the regional records are nuts.

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Rees Cat Ophuls @reescatophuls.bsky.social · Apr 24

Are three of the global warming datasets at risk of degraded data/staff? NOAA, GISS, and Berkeley Earth (which I believe uses similar/overlapping data with NOAA). Copernicus and HadCRUT are presumably ok for the foreseeable.

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