John Kennedy

Screenshot of figures from the paper: Above a graph showing wiggly lines depicting the cumulative mass budget of Antarctica: a dark line swoops and wiggles downwards before stabilising at the end, colourful dashed lines (depicting snow fall) wiggle along constantly before sloping upwards at the same tme stabilisation occurs. Below 6 maps of Antarctica in blues and red depicting the mass change in different basins.

🚨 New @oceaniceeu.bsky.social preprint🚨 why has Antarctica stopped (net) losing mass, in spite of increased discharge?
Declining sea ice is part of the answer but increasingly heavy and frequent atmospheric rivers are most important factor.

Lots of important subtleties:
arxiv.org/abs/2510.03590

Open Ocean #10 In which I attempt maths and experience regret.

Open Ocean #10

In which I attempt maths and experience regret. But at least my mean ends up in about the right place.

diagrammonkey.wordpress.com/2025/10/06/o...

Open Ocean #10 In which I attempt maths and experience regret.

Open Ocean #10

In which I attempt maths and experience regret. But at least my mean ends up in about the right place.

diagrammonkey.wordpress.com/2025/10/06/o...

Open Ocean #9 Lots of little things

Open Ocean #9

Lots of little things

diagrammonkey.wordpress.com/2025/10/05/o...

Nominate an Impactful Dataset You are invited to nominate a dataset to be included in a commentary about the impact of Earth, space, and environmental data using the dimensions of people, planet, and prosperity. Selected submitter...

⭐️Nominate an Impactful Dataset

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Submit nominations by 20 October.

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@agubiogeosciences.bsky.social

Open Ocean #9 Lots of little things

Open Ocean #9

Lots of little things

diagrammonkey.wordpress.com/2025/10/05/o...

Graph showing global mean temperature for Septembers from 1850 to 2025. Seven datasets are shown: HadCRUT5, NOAAGlobalTemp v6, GISTEMP, two flavours of Berkeley Earth, JRA-3Q and ERA5.

September global mean temperature is going to take a big leap from August it looks like. I looked at the mean of the daily averages from ERA5 and on an anomaly basis it's much warmer than August was and way above anything before the huge 2023 lurch.

I was supposed to drop the map of anomalies into this thread... It's quite warm in lots of places but there are some large anomalies over the NH.

bsky.app/profile/mice...

Map of surface air temperature anomales from ERA5 for September 2025. Red areas are warmer than the 1991-2020 average and blue areas are colder than it. There are four different logos along the bottom of the graph and one of them appears twice.

The anomalies locally look like this...

(from pulse.climate.copernicus.eu)

Graph showing monthly global mean temperature from 2014 to September 2025. Seven datasets are shown: HadCRUT5, NOAAGlobalTemp v6, GISTEMP, two flavours of Berkeley Earth, JRA-3Q and ERA5.

You can see the September bounce here too in a plot of all monthly averages. It will be interesting to see the final ERA5 figures.

Graph showing global mean temperature for Septembers from 1850 to 2025. Seven datasets are shown: HadCRUT5, NOAAGlobalTemp v6, GISTEMP, two flavours of Berkeley Earth, JRA-3Q and ERA5.

September global mean temperature is going to take a big leap from August it looks like. I looked at the mean of the daily averages from ERA5 and on an anomaly basis it's much warmer than August was and way above anything before the huge 2023 lurch.

Open Ocean #8 Extending the SST data further back in time and the wonderful horrors of ICOADS.

Open Ocean #8

Extending the SST data further back in time and the wonderful horrors of ICOADS.

diagrammonkey.wordpress.com/2025/10/01/o...

Open Ocean #8 Extending the SST data further back in time and the wonderful horrors of ICOADS.

Open Ocean #8

Extending the SST data further back in time and the wonderful horrors of ICOADS.

diagrammonkey.wordpress.com/2025/10/01/o...

Open Ocean #7 Using a simple interpolation scheme to estimate biases in the ship data and create a bias adjusted dataset

Open Ocean #7

Using a simple interpolation scheme to estimate biases in the ship data and create a bias adjusted dataset.

diagrammonkey.wordpress.com/2025/09/30/o...

Open Ocean #7 Using a simple interpolation scheme to estimate biases in the ship data and create a bias adjusted dataset

Open Ocean #7

Using a simple interpolation scheme to estimate biases in the ship data and create a bias adjusted dataset.

diagrammonkey.wordpress.com/2025/09/30/o...

Invincibly ignorant is a thing.

Open Ocean #6 Implementing a pattern-based reconstruction technique that works by – I swear – pure magic.

Open Ocean #6

Implementing a pattern-based reconstruction technique that works by – I swear – pure magic.

diagrammonkey.wordpress.com/2025/09/28/o...

Open Ocean #6 Implementing a pattern-based reconstruction technique that works by – I swear – pure magic.

Open Ocean #6

Implementing a pattern-based reconstruction technique that works by – I swear – pure magic.

diagrammonkey.wordpress.com/2025/09/28/o...

Open Ocean #5 Interpolating anomalies in the simple gridder to produce globally complete fields.

Open Ocean #5

Interpolating anomalies in the simple gridder to produce globally complete fields.

diagrammonkey.wordpress.com/2025/09/27/o...

Open Ocean #4 In which I estimate sampling uncertainties for my simple gridder.

Open Ocean #4

In which I estimate sampling uncertainties for my simple gridder.

diagrammonkey.wordpress.com/2025/09/26/o...

Open Ocean #4 In which I estimate sampling uncertainties for my simple gridder.

Open Ocean #4

In which I estimate sampling uncertainties for my simple gridder.

diagrammonkey.wordpress.com/2025/09/26/o...

That’s *the* cropolis.

Open Ocean #3 Last time, I did some comparisons between HadSST4 (unadjusted data) and the output from the simple gridder. They were pretty close to each other. I ended up by showing that the number of occupied g…

Open Ocean #3

Estimating ship-buoy biases with a simple gridder.

diagrammonkey.wordpress.com/2025/09/24/o...

There's another fault line: people who really look at their data and people who don't.

Open Ocean #3 Last time, I did some comparisons between HadSST4 (unadjusted data) and the output from the simple gridder. They were pretty close to each other. I ended up by showing that the number of occupied g…

Open Ocean #3

Estimating ship-buoy biases with a simple gridder.

diagrammonkey.wordpress.com/2025/09/24/o...

Yes, it is bad teaching. The "right" way, you propose, postpones the punchline but it is admirably chaotic.

Thanks! That's nice to hear.

At the risk of saying something I will come to regret, the world needs more blogging scientists.

That is exactly how I used git for years.

You don't use git? Oh wow. OK. It's really cool. What's that? You heard it's kind of difficult. Nah, it's really simple. How does it work? Well, you just need to know a little graph theor... Hey! Where are you going?

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