Rees Cat Ophuls

@reescatophuls

Analytical Graphics for Climate Change and Planetary Boundaries. Some graphics risk being impenetrable ¯\_(ツ)_/¯ Fan of Williams' Rees, Catton, Ophuls

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Rees Cat Ophuls@reescatophuls· 29d

The @metoffice.gov.uk did a different graph (UK only, and y-axis is the %-of-land-which-is-within-certain-temperature-bands) ... Which has a similar look and feel. Would be interesting if it is possible to do a global version of this. youtu.be/9PKw_oFzj-M?...

Graph showing how how the area of UK land, which has a given temperature band, has changed over time

X axis years 1880 to 2025
Y axis: percentage of uk land area
Colours: annual mean temperature.

It looks like coloured bands, showing that over time less of the UK land has lower temperatures and more of the land has higher average annual temperatures.

Rees Cat Ophuls@reescatophuls· Jul 11

July 2026 Update - So far 2026 has been in and around the 1.5C global warming milestone. What will the December update bring, as El Nino presumably starts to affect us? Data: Copernicus ERA 5 - @copernicusecmwf.bsky.social #ClimateChange #GlobalBoiling

Rees Cat Ophuls@reescatophuls· Jul 8

Global Temperature Anomalies over the previous 365 days: * 100% over 1.1°C * 35% over 1.5°C * 3% over 1.7°C Has the 365 day running average bottomed out? Will the much discussed El Nino start to drive temperatures up again? #ClimateChange #GlobalBoiling

Graph showing percent of days (in the last 365 days) over various global warming milestones.
> X-Axis is the date 1st Jan 2000 until 6th July 2026.
> Y-Axis is the percentage of the preceding 365 days, which are above different global mean surface temperature (GMST) anomaly milestones.

Example
On 6th July 2026, the previous 365 days had:
* 100.0% days over 1.1C
* 96.2% days over 1.2C
* 84.7% days over 1.3C
* 60.8% days over 1.4C
* 34.8% days over 1.5C
* 14.0% days over 1.6C
* 3.3% days over 1.7C
* 0.8% days over 1.8C
* 0.0% days over 1.9C

> The plot looks like a set of coloured waves, where each wave is a different GMST anomaly (0.2C, 0.3C, etc), and shows the temperatures increasing and decreasing over roughly 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, June 2025, November 2025, March 2026
> How the graph was created:
https://parisagreementtemperatureindex.com/warming-tapestry-percent-days-over-milestone/

Rees Cat Ophuls@reescatophuls· May 21

The 3.5 Year Average for Global Warming is passing 1.5C The 3 Year Average passed 1.5C less than 7 months ago The 2 Year Average passed 1.5C in November 2024 What is the longest running average, that equals 1.5C for any given date? What about Milestones: 0.5C, 0.75C, 1C, 1.25C, 1.75C Data: ERA5

Image is of a Graph
X-Axis: Years 1980 until May 2026
Y-Axis: For a Given Date, what is the longest period where the running average equals a Global Warming Milestone. The Y-Axis values are from 0-year-running-average up to 20-year-running-averageThere is one line for each of the Global Warming Milestones (0.5C, 0.75C, 1C, 1.25C, 1.5C, 1.75C)

Example: For 1.00C Global Warming (E.g. Global Surface Mean Temperature Anomaly), there is a line, which starts in 1998 and bumps along the x-axis before shooting up from around the year 2004, and reaches the top of the graph in December 2020. E.g. in 2004 the longest running average that equals 1C started to be consistently above zero. By December 2020 the longest running average that equaled 1C, was 20-year-running-average.

The overall impression of the graph, is that when the global temperature start to reach a warming milestone, you get short periods (months) where the global warming running average reaches that milestone. By the time the longest running average reaches around 3-8 years, then, the longest running average just keeps going up. One could argue that we crossed that milestone at the center date of the running average. E.g. 10years before the 20-year-running-average reached the milestone.

Further details on how the graph was created, commentary, and what sanity checks were performed are available at: https://parisagreementtemperatureindex.com/longest-running-average/

Rees Cat Ophuls@reescatophuls· May 1

The Arctic Sea Ice Volume is at its yearly maximum. There is a lot less thick ice than there was 22 years ago. Source: polarportal.dk/en/sea-ice-a... At the time, May 2004 was considered to be a very low year for sea-ice-extent (For volume, I'm not sure) Source: theecologist.org/2016/jun/10/...

Two maps of the Arctic side by side, showing the thickness of the sea ice. The lefthand map is from May 2004, the righthand map is from May 2026. The sea ice extent is similar, but there is way less thick ice in 2026.

Rees Cat Ophuls@reescatophuls· Apr 23

@edhawkins.org has updated the showyourstripes.info to include 2025. 2025 is confirmed to be the same colour as 2023 and 2024. The latest show-your-stripes does appear to change the colour of a few years (1989, 2010), compared to what the stripes showed previously.

Graph called "Global Temperatures have increased by around 1.4C"
Graph shows one vertical coloured line per year, from 1850-2025.
The colours are from the https://showyourstripes.info/ website and represent the warming.
The height of the vertical lines represents the global average warming anomaly for that year.

Rees Cat Ophuls@reescatophuls· Apr 1

GMST Anomaly data is noisy. The loess-30-yr trend line shifts as the latest data is added. We are now at 1.45C. I will be interesting to see when the loess-30-year first crosses 1.5C and what date it finally settles at.

Rees Cat Ophuls@reescatophuls· Apr 1

900 individual days have been 1.5C or more, above the Pre-Industrial baseline A third of the days in the last 12 months have been 1.5C or more. It will be interesting to see if we get over 1000 days in 2026. We will if the remainder of 2026 is similar to 2023 or 2024, but not if similar to 2025.

Graph purpose: Show both the individual days of global warming, and the longer term trends.
X-Axis: Years, from Jan 1940 until 30th March 2026
Y-Axis: Cumulative number of days above different global warming milestones (Log scale, from 0 to 10,000 days).
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 30th March 2026, there have cumulatively been 900 individual days at-or-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 Loess 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 2012 (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.
Note that this graph annotates numbers “>“, however it is actually: round to 2 decimal places, and then use ">=", so 1.495 will count as being 1.5 which is “>=“ 1.5C. I did this, as it was the only way I could get the numbers to match the 6 days that Copernicus reported as being at least 2C.

Rees Cat Ophuls@reescatophuls· Mar 10

Global Warming surging upwards in waves. The last 365 days: * 100% over 1.0C * 35% over 1.5C * 4% over 1.7C The post 2024 mega-surge still hasn't bottomed out. El Nino is rearing its head in the forecasts, hinting at higher temperatures to come? #ClimateChange #GlobalBoiling

The image is a graph.
X-Axis is the date 1st Jan 2000 until 8th March 2026.
Y-Axis is the percentage of the preceding 365 days, which are above different global mean surface temperature (GMST) anomaly milestones.

Example
On 8th March 2026, the previous 365 days had:
* 100.0% days over 1.0C
* 98.4% days over 1.1C
* 94.2% days over 1.2C
* 80.5% days over 1.3C
* 58.4% days over 1.4C
* 35.1% days over 1.5C
* 16.2% days over 1.6C
* 4.4% days over 1.7C
* 0.3% days over 1.8C
* 0.0% 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 (0.2C, 0.3C, etc), and shows the temperatures increasing and decreasing over roughly 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, June 2025, November 2025

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

Rees Cat Ophuls@reescatophuls· Jan 27

This 3rd projection in this "Global Warming Futures Series" and projects a future following a "Highest Possible Ambition" trend as included in the ICCI's "State of the Cryosphere Report 2025". I'm a lay person, but I'll be astounded if we follow this path without geo-engineering. 3/x

This graph is the third of a series of graphs showing when we might see the first day / month / year over various global warming milestones.

Climate Scientists and institutions have published various projections for how Global Warming might proceed.

This graph assumes the future Global Warming will follow a "Highest Possible Ambition" line, as per a graph posted in the ICCI's "State of the Cryosphere Report 2025":
> https://iccinet.org/statecryo25/
> https://doi.org/10.5281/zenodo.18153190

If I use this projections and make a few assumption about natural variability, I can come up with plausible dates after which we might see the first day, first month and first year over various global warming milestones (1.5°C, 2.0°C, 2.5°C, 3.0°C). Also, this would show dates by which we may have seen the last day, last month, last year under various Global Warming Milestones.

The graphic shows:
X-Axis: The years 1970 to 2050
Y-Axis: The Global Warming Anomaly -0.5°C to 3.0°C

There is a trend line which show the global warming from 1970 until present, and then the trend line is projected forwards to 2050.

I have used a series of functions to get close to the "Highest Possible Ambition" trendline from a diagram included in the ICCI's "State of the Cryosphere Report 2025".

The graph also plots data from Copernicus ERA5, with daily anomalies, monthly anomalies and yearly anomalies.

The graph also plots shaded areas, which show the times where we could expect different daily/monthly/yearly anomalies to happen.

There are tables which show selected years, such as the first year we might get a year over 1.5°C, or over 2.0°C. The tables to the same for daily and monthly anomalies.

See https://parisagreementtemperatureindex.com/global-warming-futures-series/ for more details, and explanations of how the graph was created and what sanity checks were applied.

Rees Cat Ophuls@reescatophuls· Jan 27

This 2nd projection in this "Global Warming Futures Series" shows when we might get the first day, first month and first year over 3°C, if the future follows an accelerating Global Warming trend, and variability is similar to the past. It also shows when we might have the last year below 2.5°C 2/x

Rees Cat Ophuls@reescatophuls· Jan 25

I was wondering when we could see our first day, first month or first year, with Global Warming above 2.5°C. Climate Scientists and Institutions have published various projections for how Global Warming might proceed. Here are a series of projections inspired by those People/Institutions. 🧵 1/x

This graph is one of a series of graphs showing when we might see the first day / month / year over various global warming milestones.

Climate Scientists and institutions have published various projections for how Global Warming might proceed.

This graph assumes a global warming of 0.306°C / Decade from now on. It is inspired by James Hansen's work.

If I use these projections and make a few assumption about natural variability, I can come up with plausible dates after which we might see the first day, first month and first year over various global warming milestones (1.5°C, 2.0°C, 2.5°C, 3.0°C). Also, this would show dates by which we may have seen the last day, last month, last year under various Global Warming Milestones.

The graphic shows:
X-Axis: The years 1970 to 2050
Y-Axis: The Global Warming Anomaly -0.5°C to 3.0°C

There is a trend line which show the global warming from 1970 until present, and then the trend line is projected forwards to 2050, with an 0.306°C / Decade warming.

The graph also plots data from Copernicus ERA5, with daily anomalies, monthly anomalies and yearly anomalies.

The graph also plots shaded areas, which show the times where we could expect different daily/monthly/yearly anomalies to happen.

There are tables which show selected years, such as the first year we might get a year over 1.5°C, or over 2.5°C. The tables to the same for daily and monthly anomalies.

See https://parisagreementtemperatureindex.com/global-warming-futures-series/ for more details, and explanations of how the graph was created and what sanity checks were applied.

Rees Cat Ophuls@reescatophuls· Jan 14

Carbon Brief collected the Global Warming Datasets for 2025 Values with common baseline (1850-1900): Average: 1.435 °C 1.45 °C NASA 1.39 °C HadCRUT5 1.41 °C NOAA 1.44 °C Berkeley Earth 1.47 °C Copernicus ERA5 1.46 °C JRA 1.44 °C DCENT 1.42 °C China-MST Source: www.carbonbrief.org/state-of-the...

Table from Carbon Brief website.
Shows the Global Warming Temperature Anomaly for 2025, for eight datasets (Nasa, Hadley, NOAA, Berkeley Earth, Copernicus, JRA, DCENT, China-MST)
For each dataset, three values are shown: Firstly, the global temperature anomaly reported by the organisation. Secondly, the same but modified to use a "common baseline" (1850-1900). Thirdly, the ranking. E.g. Third hottest year in the dataset.

The values range between 1.39°C and 1.53°C, with the average around 1.43°C

Rees Cat Ophuls@reescatophuls· Jan 4

A new version of "We need a bigger Y Axis". The Arctic Sea Ice Volume on 4th Jan 2026, is so low, that it is hiding behind the key. Source: polarportal.dk/en/sea-ice-a... - by @polarportal.bsky.social

Two Images of the Arctic Sea Ice on 4th January 2026.

The main image shows a map of the Arctic Sea Ice with colours indicating the thickness of the sea ice at any point on the map.

The top right, has a graph, which shows how the Arctic Sea Ice volume throughout the year (x-axis is January to December). The graph shows one line for each of the years 2022-2026. The graph has a key (showing which colour line is which year), but the line for 2026 is going behind the key and will be hidden for a few days. Presumably, if Arctic sea ice melt continues, (then unless the key is moved), the line will be hidden for ever longer periods of time. Up to 4 months if we get near a BOE. I'm guessing they will update the graph at some point.

Rees Cat Ophuls@reescatophuls· Dec 22

How long does it take from the first appearance of a global warming milestone, to it being permanent? 2025: 3rd successive year with at least one month reaching 1.75 We have now had 32 consecutive months over 1.25C This graphic has smoothing. The last three years were 6, 11 and 6 months over 1.5C

Graph shows how many months per year are above various global warming milestones.

x-axis: 1945 to 2025 (inclusive).
y-axis: Number of months per year above a global warming milestone.

E.g. 1982 has 2 months above 0.75C GMST anomaly.

There are 6 lines, each representing a global warming milestone (0.5C, 0.75C, 1C, 1.25C, 1.5C, 1.75C). We started having global warming with months over 0.5C in 1950s, and by early 2000s all 12 months were always over 0.5C. The other lines have a similar trajectory, but different dates.

Note that smoothing is applied to make the trends less jumpy.
E.g. 2023/2024/2025 has 6/11/6 months over 1.5C respectively, but it smooths out to 8 months for 2024 and 2025.

My website has the raw-data version of this graphic.
https://parisagreementtemperatureindex.com/months-above-climate-milestones/

Updates compared to previous posting of this graph
* Includes 2025 data. It is now 22nd Dec 2025, and there is enough data / projections, to know (with high confidence that December 2025 will be above 1.25C and below 1.5C).
* This uses the Copernicus ERA5 Dataset with pre-industrial baseline.
* Graph runs from 1945 -> 2025 (inclusive).
* Smoothing continues to use 3-year-centred-average, (and 2-year weighted running average for 2025).

Rees Cat Ophuls@reescatophuls· Dec 12

2025 Update. Spiralling Past 1.5C Paris Agreement Lower Limit Data: Copernicus ERA 5 - @copernicusecmwf.bsky.social #ClimateChange #GlobalBoiling

Rees Cat Ophuls@reescatophuls· Nov 12

An update to a classic #ClimateInactionStripes #ShowYourStripes CC: @tadziomueller.bsky.social

Rees Cat Ophuls@reescatophuls· Nov 9

Global Warming surging upwards in waves. The last 365 days: * 100% over 1.0C * 50% over 1.5C * 4% over 1.8C The post 2024 mega-surge hasn't fully bottomed out yet. What will 2026 bring us? #ClimateChange #GlobalBoiling

The image is a graph.
X-Axis is the date 1st Jan 2000 until 7th November 2025.
Y-Axis is the percentage of the preceding 365 days, which are above different global mean surface temperature (GMST) anomaly milestones.

Example
On 7th September 2025, the previous 365 days had:
* 100.0% days over 1.0C
* 98.4% days over 1.1C
* 94.8% days over 1.2C
* 84.9% days over 1.3C
* 69.6% days over 1.4C
* 50.1% days over 1.5C
* 34.2% days over 1.6C
* 16.2% days over 1.7C
* 3.6% 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 (0.2C, 0.3C, etc), 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, June 2025

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

Rees Cat Ophuls@reescatophuls· Nov 6

My previous post begs for this one It asks the question: Has waiting for a 20 year average made much difference in the past? This new graphic takes the previous one (longest running average for a given date), and for each point on the graph, draws a line back to the “centred-moving-average” date

This graph is a bit of head-scratcher.

The starting logic, is to note that different people suggest using a 10-year average or 20-year average to get the current global warming state.

This graph tries to answer the question: In the past, has there been any benefit to waiting for the 20-year-average.

X-Axis: Years 1980 to 2026
Y-Axis: For a Given Date, what is the longest period where the running average equals a Global Warming Milestone. The values are from 0-year-longest-running-average up to 20-year-longest-running-average. Then for each point plotted on the graph draw a line back to the date, where the centered-moving-average has the same value.

E.g. In December 1995 the 20 year average crossed 0.5C Global Warming. So that means, in December 1985, the 20 year centered-moving-average crossed 0.5C

E.g. In November 2004 the 10 year average crossed 0.75C Global Warming. So that means, in November 1999, the 10 year centered-moving-average crossed 0.75C

There is one line for each of the Global Warming Milestones (0.5C, 0.75C, 1C, 1.25C, 1.5C, 1.75C)

Example: For 1.00C Global Warming (E.g. Global Surface Mean Temperature Anomaly), there is a line, which starts in 1998 and bumps along the x-axis before shooting up from around the year 2004, and reaches the top of the graph in December 2020. E.g. in 2020, the 20-year running average was 1.C.

Then, for each point plotted on the graph draw a faint gray horizontal line, back to the date for the centered-moving-average. The thing that is interesting, is that back in the 80s, the centered-moving-average date, at which a milestone was crossed moved forwards in time. More recently the centered-moving-average date actually is static, or even moves back in time ! Also the main lines are getting closer together.

Further details on how the graph was created, commentary, and what sanity checks were performed are available at: https://parisagreementtemperatureindex.com/longest-running-average

Rees Cat Ophuls@reescatophuls· Nov 6

The 3 Year Average for Global Warming just passed 1.5C The 2 Year Average passed 1.5C in November 2024 I wondered: what is the longest running average, that equals 1.5C for any given date What about the other Global Warming Milestones: 0.5C, 0.75C, 1C, 1.25C, 1.75C Data: ERA5

Image is of a Graph
X-Axis: Years 1980 to 2026
Y-Axis: For a Given Date, what is the longest period where the running average equals a Global Warming Milestone. The Y-Axis values are from 0-year-running-average up to 20-year-running-averageThere is one line for each of the Global Warming Milestones (0.5C, 0.75C, 1C, 1.25C, 1.5C, 1.75C)

Example: For 1.00C Global Warming (E.g. Global Surface Mean Temperature Anomaly), there is a line, which starts in 1998 and bumps along the x-axis before shooting up from around the year 2004, and reaches the top of the graph in December 2020. E.g. in 2004 the longest running average that equals 1C started to be consistently above zero. By December 2020 the longest running average that equaled 1C, was 20-year-running-average.

The overall impression of the graph, is that when the global temperature start to reach a warming milestone, you get short periods (months) where the global warming running average reaches that milestone. By the time the longest running average reaches around 3-8 years, then, the longest running average just keeps going up. One could argue that we crossed that milestone at the center date of the running average. E.g. 10years before the 20-year-running-average reached the milestone.

Further details on how the graph was created, commentary, and what sanity checks were performed are available at: https://parisagreementtemperatureindex.com/longest-running-average/

Rees Cat Ophuls@reescatophuls· Oct 22

Just noticed that the Berkeley Earth data already has the 3-year average over 1.5C

A table showing the Berkeley Earth data for global warming.
It has 2022 Sept/Oct/NovDec, 2023 year, 2024 year, 2025 jan to aug
It shows that when they are all added up, the 3 year running average is over 1.5C

Contents of the table
2022 September 1.24 https://berkeleyearth.wpengine.com/september-2022-temperature-update/
2022 October 1.37 https://berkeleyearth.wpengine.com/october-2022-temperature-update/
2022 November 1.1 https://berkeleyearth.wpengine.com/november-2022-temperature-update/
2022 December 1.25 Admittedly, I can't find a reference for this. It is calculated from their raw data
2023 YEAR 1.54 https://berkeleyearth.org/global-temperature-report-for-2023/
2024 YEAR 1.62 https://berkeleyearth.org/global-temperature-report-for-2024/
2025 January 1.64 https://berkeleyearth.org/january-2025-temperature-update/
2025 February 1.49 https://berkeleyearth.org/february-2025-temperature-update/
2025 March 1.55 https://berkeleyearth.org/march-2025-temperature-update/
2025 April 1.49 https://berkeleyearth.org/april-2025-temperature-update/
2025 May 1.33 https://berkeleyearth.org/may-2025-temperature-update/
2025 June 1.31 https://berkeleyearth.org/june-2025-temperature-update/
2025 July 1.29 https://berkeleyearth.org/july-2025-temperature-update/
2025 August 1.42 https://berkeleyearth.org/august-2025-temperature-update/

3 year average 1.51

Rees Cat Ophuls@reescatophuls· Sep 24

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.

Rees Cat Ophuls@reescatophuls· 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/

Rees Cat Ophuls@reescatophuls· 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/

Rees Cat Ophuls@reescatophuls· 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

Rees Cat Ophuls@reescatophuls· 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

Rees Cat Ophuls@reescatophuls· 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/

Rees Cat Ophuls@reescatophuls· Apr 15

Hi @leonsimons.bsky.social Below is the linear-y-axis version of the same graph. The 1.75C and 2.00C lines are (unsurprisingly) no longer visible. Details in Alt Text

Rees Cat Ophuls@reescatophuls· Apr 14

I was wondering if the percentage-of-days above a global warming milestone was fairly steady, at the point the trend line passed that milestone. I settled on using percent-of-days-in-previous-7-years that were over a given milestone. An ugly, but interesting graph. Explanation in the Alt Text.

X-Axis - Dates from 1970 -> April 2025 (12th April)
Y-Axis - Cumulative days (since 1940) above global warming milestones
Data uses Copernicus ERA5 data, with anomalies above 1850-1900 pre-industrial period.

The top line is "days over 0.5C global warming anomaly"
The one-but-top line is "days over 0.75C ..."

The colours are the interesting point in this graph.
I worked out the percentage of the previous-2555-days that are over the given global warming milestone.

E.g. the top line, show that since around 2011, 100% of the previous 2555 days (7-years, 7*365 days) are above 0.5C global warming anomaly.

The vertical lines, leading down to the grey box shows what date the Loess-30-year-window trend line, passed a given global warming milestone.

It looks like, when about 20-40% of the previous 7-years are above a given global warming milestone, the loess-30-year-window trend crosses that milestone.

Overall, just one more indication that we are getting very close to the trend crossing 1.5C.

Why did I choose 7-year average? I wanted a long enough period to reduce the variations from things like the la-nina/el-nino cycle.

See:
* Dataset: https://parisagreementtemperatureindex.com/gmst-data-sets/
* Calculating Anomalies: https://parisagreementtemperatureindex.com/copernicus-1850-1900-baseline-daily-gmst/
* Creating cumulative graph: https://parisagreementtemperatureindex.com/1000-day-climate-graphic-design/

Rees Cat Ophuls@reescatophuls· Apr 5

Arctic sea ice volume very low too, for this time of year. Source: polarportal.dk/en/sea-ice-a...