Dr Joanne Williams
@jowilliams.bsky.social
Sea-level and tidal scientist. Liverpool, UK.
Opinions own!
Opinions own!
Pinned
![[Single frame, with Megan and Cueball standing at a coastline with grass, with water and waves visible. They are looking at the ocean and are standing together.]
Cueball: Hey, where's that big island we were looking at this morning?
Megan: Oh, it's underwater. The ocean's depth here goes up and down by like ten feet every day.
Cueball: What?
Megan: It's because the planet has a big moon orbiting near the surface. It causes weird gravity effects.
Cueball: What???
[Caption below the frame:]
People here are used to them, but tides are one of the weirdest and most sci-fi elements of life on Earth.
Transcript thanks to explainxkcd](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:d67aicqw6nicsf7cjauvzuo3/bafkreibnctesneis67q7qz6tgdszao5vn2zzjlqzdblcy4h6vygipyclni@jpeg)
Hooray, an @xkcd.com about tides! Although only little ones, round here we can get a tidal range of 10 *metres* .
xkcd.com/3135/
xkcd.com/3135/
Good point. And a reminder that Bluesky has an option of timed mute words, if you want to mute otherwise common words for a few days but not necessarily permanently.
(Like to stop Traitors Spoilers, my one-day mute words included "alan" and "cat"!)
(Like to stop Traitors Spoilers, my one-day mute words included "alan" and "cat"!)
Rough day to be any sort of survivor of sexual violence. Solidarity to all of you, please be kind to yourselves
November 13, 2025 at 11:53 AM
Good point. And a reminder that Bluesky has an option of timed mute words, if you want to mute otherwise common words for a few days but not necessarily permanently.
(Like to stop Traitors Spoilers, my one-day mute words included "alan" and "cat"!)
(Like to stop Traitors Spoilers, my one-day mute words included "alan" and "cat"!)
Very pleased to see @eleanorfrajka.bsky.social will be giving a Keynote Plenary at AGU #osm26 in Glasgow. 🌊
www.agu.org/ocean-scienc...
www.agu.org/ocean-scienc...
Schedule | Ocean Sciences Meeting 2026
The #OSM26 schedule at a glance, available session formats, keynote and plenary speakers, special events, and more will be highlighted here. Please check back regularly for more details and updates.
https://www.agu.org/ocean-sciences-meeting/schedule#plenaries#Frajka-Williams
November 13, 2025 at 9:40 AM
Very pleased to see @eleanorfrajka.bsky.social will be giving a Keynote Plenary at AGU #osm26 in Glasgow. 🌊
www.agu.org/ocean-scienc...
www.agu.org/ocean-scienc...
Reposted by Dr Joanne Williams
Refinding joy in exploring streamflow data 😍 just looking at the stories gages tell about rivers.
Here’s the Allagash River (ME), 1980–2020. Each line: a year of daily flow (Jan–Dec). Colors show each day compared to normal: green ≈ normal, blue = high, red = low. 🌊💧
#Hydrology #DataViz #sciArt
Here’s the Allagash River (ME), 1980–2020. Each line: a year of daily flow (Jan–Dec). Colors show each day compared to normal: green ≈ normal, blue = high, red = low. 🌊💧
#Hydrology #DataViz #sciArt
November 12, 2025 at 6:54 PM
Refinding joy in exploring streamflow data 😍 just looking at the stories gages tell about rivers.
Here’s the Allagash River (ME), 1980–2020. Each line: a year of daily flow (Jan–Dec). Colors show each day compared to normal: green ≈ normal, blue = high, red = low. 🌊💧
#Hydrology #DataViz #sciArt
Here’s the Allagash River (ME), 1980–2020. Each line: a year of daily flow (Jan–Dec). Colors show each day compared to normal: green ≈ normal, blue = high, red = low. 🌊💧
#Hydrology #DataViz #sciArt
Reposted by Dr Joanne Williams
I am hiring 4 postdoctoral researchers for up to 4 years each. Topics include ice sheet reconstruction, GIA, spatial stats, and satellite geodesy. Based in Tasmania.
All details are here: careers.utas.edu.au/en/listing/ with titles below
I am also recruiting multiple PhD students (see below)
1/n
All details are here: careers.utas.edu.au/en/listing/ with titles below
I am also recruiting multiple PhD students (see below)
1/n
Current Vacancies
careers.utas.edu.au
November 13, 2025 at 3:04 AM
I am hiring 4 postdoctoral researchers for up to 4 years each. Topics include ice sheet reconstruction, GIA, spatial stats, and satellite geodesy. Based in Tasmania.
All details are here: careers.utas.edu.au/en/listing/ with titles below
I am also recruiting multiple PhD students (see below)
1/n
All details are here: careers.utas.edu.au/en/listing/ with titles below
I am also recruiting multiple PhD students (see below)
1/n
A thread about cathedrals built on swamps*.
If you want a system to work for 100+ years, it's probably not efficient to build it on a system you'll have to upgrade every 2.
*I thought I was confusing Salisbury and Winchester as The Swamp Cathedral. Haha no it's both.
If you want a system to work for 100+ years, it's probably not efficient to build it on a system you'll have to upgrade every 2.
*I thought I was confusing Salisbury and Winchester as The Swamp Cathedral. Haha no it's both.
the thing about tech like this is that it fails. a lot. power cuts occasionally, wifi signal is bad, a sheep chews a cable, a software update blows the system. so much of what we do in longterm building conservation is low-tech because it works and is reliable.
bsky.app/profile/worl...
bsky.app/profile/worl...
Surely in 2025 the Holy Dipstick could be a 24-7 sensor that directly links to a computer that operates the sluice gate control?
Or is this a TRADITION situation
Or is this a TRADITION situation
November 12, 2025 at 4:11 PM
A thread about cathedrals built on swamps*.
If you want a system to work for 100+ years, it's probably not efficient to build it on a system you'll have to upgrade every 2.
*I thought I was confusing Salisbury and Winchester as The Swamp Cathedral. Haha no it's both.
If you want a system to work for 100+ years, it's probably not efficient to build it on a system you'll have to upgrade every 2.
*I thought I was confusing Salisbury and Winchester as The Swamp Cathedral. Haha no it's both.
Reposted by Dr Joanne Williams
Athelstan Spilhaus, a geophysicist, oceanographer, and inventor at WHOI, spent his life redefining boundaries on maps, technological possibilities, and how people imagined the future.
Learn more about this ocean pioneer: go.whoi.edu/spilhaus
Learn more about this ocean pioneer: go.whoi.edu/spilhaus
November 12, 2025 at 3:00 PM
Athelstan Spilhaus, a geophysicist, oceanographer, and inventor at WHOI, spent his life redefining boundaries on maps, technological possibilities, and how people imagined the future.
Learn more about this ocean pioneer: go.whoi.edu/spilhaus
Learn more about this ocean pioneer: go.whoi.edu/spilhaus
The headline: "Northern Lights set to dazzle UK once again tonight"
The forecast: 🌧️🌧️😭
The forecast: 🌧️🌧️😭
November 12, 2025 at 10:50 AM
The headline: "Northern Lights set to dazzle UK once again tonight"
The forecast: 🌧️🌧️😭
The forecast: 🌧️🌧️😭
Another example of "hey, we could use the noise in GPS to measure..." This time it's the ionospheric delay being used to observe tsunami propagation in near real time (10s of minutes). @sdpwilliams.bsky.social @funwithgps.bsky.social www.bbc.co.uk/future/artic...
'It sounded kind of crazy': How ripples in the high atmosphere warned scientists of a tsunami in real time
Tsunamis are notoriously difficult to spot on the open ocean as they race towards shore. But in the summer of 2025, scientists watched one unfold as it happened.
www.bbc.co.uk
November 12, 2025 at 8:12 AM
Another example of "hey, we could use the noise in GPS to measure..." This time it's the ionospheric delay being used to observe tsunami propagation in near real time (10s of minutes). @sdpwilliams.bsky.social @funwithgps.bsky.social www.bbc.co.uk/future/artic...
Reposted by Dr Joanne Williams
I could imagine if sediment continued to fill up the area around them, given enough geologic time maybe the Great Lakes drain and begin solidifying into rock then it would fossilize? Also not a geologist so 🤷🏻♂️
November 11, 2025 at 7:22 AM
I could imagine if sediment continued to fill up the area around them, given enough geologic time maybe the Great Lakes drain and begin solidifying into rock then it would fossilize? Also not a geologist so 🤷🏻♂️
Is this the beginning of a fossilisation process? ⚒
(If you’re unaware of this, Superior is so cold and the depths so anoxic that bodies do not decompose. Everyone who’s gone down in it is still there, barring heroic recovery efforts. Many of them may have saponified and become “soap mummies,” which can effectively preserve them forever.
November 11, 2025 at 7:07 AM
Is this the beginning of a fossilisation process? ⚒
Reposted by Dr Joanne Williams
November 10, 2025 at 2:13 PM
Reposted by Dr Joanne Williams
🌊Online Ocean Tipping Points talk🗣️
Next Monday we’re hosting a panel of experts to discuss Ocean Tipping Points, as part of #COP30 Virtual Ocean Pavilion webinar series.
Add to your calendar 🗓️
brnw.ch/oceantipping...
🇧🇷 10:00 GMT-3
🇬🇧 13:00 GMT
#UNOceanDecade #TippingPoints #GTPR2025 #OceanScience
Next Monday we’re hosting a panel of experts to discuss Ocean Tipping Points, as part of #COP30 Virtual Ocean Pavilion webinar series.
Add to your calendar 🗓️
brnw.ch/oceantipping...
🇧🇷 10:00 GMT-3
🇬🇧 13:00 GMT
#UNOceanDecade #TippingPoints #GTPR2025 #OceanScience
November 10, 2025 at 4:53 PM
🌊Online Ocean Tipping Points talk🗣️
Next Monday we’re hosting a panel of experts to discuss Ocean Tipping Points, as part of #COP30 Virtual Ocean Pavilion webinar series.
Add to your calendar 🗓️
brnw.ch/oceantipping...
🇧🇷 10:00 GMT-3
🇬🇧 13:00 GMT
#UNOceanDecade #TippingPoints #GTPR2025 #OceanScience
Next Monday we’re hosting a panel of experts to discuss Ocean Tipping Points, as part of #COP30 Virtual Ocean Pavilion webinar series.
Add to your calendar 🗓️
brnw.ch/oceantipping...
🇧🇷 10:00 GMT-3
🇬🇧 13:00 GMT
#UNOceanDecade #TippingPoints #GTPR2025 #OceanScience
Reposted by Dr Joanne Williams
Lugged a suitcase packed to the density of a neutron star all the way from London to Exeter to perform a science show based on “How to Find a Rainbow”. Kit includes an old-fashioned slide projector, various bits of glassware, a metal clamp and stand, bottles of vegetable oil, vinegar, a red cabbage
How To Find a Rainbow
“This charming story can be read on two levels – that of two sisters in search of a physical rainbow and that of emerging from a gloomy emotional episode and beginning to find joy again. It …
alomshaha.com
November 11, 2025 at 6:13 AM
Lugged a suitcase packed to the density of a neutron star all the way from London to Exeter to perform a science show based on “How to Find a Rainbow”. Kit includes an old-fashioned slide projector, various bits of glassware, a metal clamp and stand, bottles of vegetable oil, vinegar, a red cabbage
Reposted by Dr Joanne Williams
One nice detail that can easily be lost in this graph - even right wingers trust the BBC more than the right wing tabloids
Here’s the same data, but with trust broken down by political views (circles are trust among people on the left, +s the right).
It’s not just that the BBC is widely consumed — it also has solid trust on both left & right, whereas trust in the biggest US media brands is hugely polarised.
It’s not just that the BBC is widely consumed — it also has solid trust on both left & right, whereas trust in the biggest US media brands is hugely polarised.
November 10, 2025 at 5:40 PM
One nice detail that can easily be lost in this graph - even right wingers trust the BBC more than the right wing tabloids
Reposted by Dr Joanne Williams
This #MapMonday we've #MoreMaps for you to explore. We've just added Survey of India half-inch to the mile maps, published between 1915 and 1948, to our website. These cover most of India and Myanmar in colourful detail. maps.nls.uk/additions/#187 #India #HistoricMaps
November 10, 2025 at 9:01 AM
This #MapMonday we've #MoreMaps for you to explore. We've just added Survey of India half-inch to the mile maps, published between 1915 and 1948, to our website. These cover most of India and Myanmar in colourful detail. maps.nls.uk/additions/#187 #India #HistoricMaps
Reposted by Dr Joanne Williams
🌊 How do we collect sea ice to measure tor trace elements and isotopes? You need a big drill to collect the core and then a lot of patience to shave down the outsides with a ceramic blade…to get clean ice to melt and analyze. Dr. Tia Anderlini on the trigger here.
November 10, 2025 at 1:13 AM
🌊 How do we collect sea ice to measure tor trace elements and isotopes? You need a big drill to collect the core and then a lot of patience to shave down the outsides with a ceramic blade…to get clean ice to melt and analyze. Dr. Tia Anderlini on the trigger here.
Reposted by Dr Joanne Williams
Quoted supporting our counterparts and friends at the Alaska Earthquake Center. The cost of the U.S. tsunami warning and mitigation effort is really a pittance. None of it has ever been adequately funded in any administration, and now things are worse. ⚒️ www.nbcnews.com/science/tsun...
U.S. tsunami warning system, reeling from funding and staffing cuts, is dealt another blow
Seismic monitoring stations in Alaska are closing after a denied federal grant, risking delayed tsunami warnings for people living on the West Coast.
www.nbcnews.com
November 9, 2025 at 7:03 PM
Quoted supporting our counterparts and friends at the Alaska Earthquake Center. The cost of the U.S. tsunami warning and mitigation effort is really a pittance. None of it has ever been adequately funded in any administration, and now things are worse. ⚒️ www.nbcnews.com/science/tsun...
This could equally apply to about 5 stories in completely different areas of the news. 👇
We have to use simplified stories to communicate and make sense of a complex world. How can we avoid the Hero/Villain narratives that cause so much harm? What are good examples of story telling that avoids it?
We have to use simplified stories to communicate and make sense of a complex world. How can we avoid the Hero/Villain narratives that cause so much harm? What are good examples of story telling that avoids it?
Collaboration and cooperation are foundations of human development. But we force our species’ story to fit one of relentless competition, because a certain sort of dickhead likes that version. Probably because they can exploit it, and declare themselves a Magic King. Ridiculous.
November 9, 2025 at 10:13 AM
This could equally apply to about 5 stories in completely different areas of the news. 👇
We have to use simplified stories to communicate and make sense of a complex world. How can we avoid the Hero/Villain narratives that cause so much harm? What are good examples of story telling that avoids it?
We have to use simplified stories to communicate and make sense of a complex world. How can we avoid the Hero/Villain narratives that cause so much harm? What are good examples of story telling that avoids it?
Reposted by Dr Joanne Williams
Look out for this later #histSTM
(And on Franklin, about whom lots of myths are circulating today, read this: www.nature.com/articles/d41...)
(And on Franklin, about whom lots of myths are circulating today, read this: www.nature.com/articles/d41...)
November 8, 2025 at 6:53 AM
Look out for this later #histSTM
(And on Franklin, about whom lots of myths are circulating today, read this: www.nature.com/articles/d41...)
(And on Franklin, about whom lots of myths are circulating today, read this: www.nature.com/articles/d41...)
Reposted by Dr Joanne Williams
It’s #RadonAwarenessWeek.
The UK Health Security Agency (UKSHA) recommends that radon levels should be reduced in homes where the annual averages is at or above 200 becquerels per cubic metre.
The UK Health Security Agency (UKSHA) recommends that radon levels should be reduced in homes where the annual averages is at or above 200 becquerels per cubic metre.
November 7, 2025 at 2:23 PM
It’s #RadonAwarenessWeek.
The UK Health Security Agency (UKSHA) recommends that radon levels should be reduced in homes where the annual averages is at or above 200 becquerels per cubic metre.
The UK Health Security Agency (UKSHA) recommends that radon levels should be reduced in homes where the annual averages is at or above 200 becquerels per cubic metre.
Reposted by Dr Joanne Williams
For the love of God please stop
November 7, 2025 at 9:56 AM
For the love of God please stop
Reposted by Dr Joanne Williams
ok, this is maybe a long shot, but anyone here using GPS tags (the ones you can put in luggage etc) for self-built surface drifters? 🌊 So far we've used raspberry-pi with a GPS module, but we have lots of connection problems, so we're looking to simplify this....
November 7, 2025 at 9:37 AM
ok, this is maybe a long shot, but anyone here using GPS tags (the ones you can put in luggage etc) for self-built surface drifters? 🌊 So far we've used raspberry-pi with a GPS module, but we have lots of connection problems, so we're looking to simplify this....
Reposted by Dr Joanne Williams
This includes coverage for approximately 99 per cent of the bedrock and approximately 95 per cent of the superficial deposits across the country.
These geological maps provide crucial information like rock types and faults, forming a valuable resource for a wide range of uses.
These geological maps provide crucial information like rock types and faults, forming a valuable resource for a wide range of uses.
November 6, 2025 at 12:35 PM
This includes coverage for approximately 99 per cent of the bedrock and approximately 95 per cent of the superficial deposits across the country.
These geological maps provide crucial information like rock types and faults, forming a valuable resource for a wide range of uses.
These geological maps provide crucial information like rock types and faults, forming a valuable resource for a wide range of uses.
Since it's coming up again in the Discourse: GPS (GNSS) is a passive system and does not itself actually track anything. The satellites just shout out their own position & time.
Your device just listens to that, works out its position, and may store or transmit that data through a phone connection.
Your device just listens to that, works out its position, and may store or transmit that data through a phone connection.
November 6, 2025 at 12:17 PM
Since it's coming up again in the Discourse: GPS (GNSS) is a passive system and does not itself actually track anything. The satellites just shout out their own position & time.
Your device just listens to that, works out its position, and may store or transmit that data through a phone connection.
Your device just listens to that, works out its position, and may store or transmit that data through a phone connection.