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Frederik Dahl Madsen

@fdmadsen

He/Him PhD student at the University of Edinburgh. Keen geophysicist with interest in Geomagnetism, Earth's Rotation, and Outreach! FRAS, Postgraduate Rep for British Geophysical Association

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01.11.2024
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Latest posts by Frederik Dahl Madsen @fdmadsen

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IGRF-14 secular variation prediction from core surface flow acceleration - Earth, Planets and Space Abstract The International Geomagnetic Reference Field (IGRF) has been regularly updated since its inception in 1965. Every recent iteration contains an estimate of the geomagnetic secular variation (...

It's been a wee while ago, but we're predicting more geomagnetic jerks! North Africa, 2028, watch this space.🧭🧲🌍

In our paper - published in @springer.springernature.com Earth Planets and Space - we use periodic signatures of core flow to forecast SV until 2030, and find 2 new jerks! πŸ”

04.03.2026 11:57 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
Comparison of the RMS of GRACE data sets (a), the residual using ISBA-CTRIP (c) and the residual using WGHM 2.2d (d). The histograms of the RMS on all grid points (top), land (middle) and ocean (bottom) are shown in (b). The RMS reductions as a result of the difference between the RMS of GRACE data sets and the residuals derived from ISBA-CTRIP (e) and WGHM 2.2d (f). Blue areas indicate regions where residual RMS is lower than that of GRACE, while red areas indicate where it is higher. Average RMS and RMS_r values over land and ocean for each data set are indicated in the bottom corners of the respective maps.

Comparison of the RMS of GRACE data sets (a), the residual using ISBA-CTRIP (c) and the residual using WGHM 2.2d (d). The histograms of the RMS on all grid points (top), land (middle) and ocean (bottom) are shown in (b). The RMS reductions as a result of the difference between the RMS of GRACE data sets and the residuals derived from ISBA-CTRIP (e) and WGHM 2.2d (f). Blue areas indicate regions where residual RMS is lower than that of GRACE, while red areas indicate where it is higher. Average RMS and RMS_r values over land and ocean for each data set are indicated in the bottom corners of the respective maps.

Published in #GJI Geophysical Journal International: "Separating climate and deep Earth signals in satellite gravimetry: a global assessment", Saraswati et al. This is Fig. 1: please visit academic.oup.com/gji/article/... to read the paper. @royalastrosoc.bsky.social @academic.oup.com

09.02.2026 08:00 πŸ‘ 5 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0
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UK universities have been criticised for offering PhD studentships with significant teaching loads, often without offering doctoral candidates extra time to complete their studies
https://ow.ly/PkKg50XU0qu

12.01.2026 07:50 πŸ‘ 2 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0
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Describing scientific disciplines as β€œbedfellows” is maybe the most fun description of cross-disciplinary science I’ve come across so far!

26.12.2025 15:59 πŸ‘ 2 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
The extent of Himalayan ranges showing the interplay between topography around intermontane basins, seismicity and population. The top panel shows nine major intermontane basins. Major thrusts across the whole extent are also highlighted which include MFT: Main Frontal Thrust, MBT: Main Boundary Thrust and MCT: Main Central thrust. Dashed lines represent extensional features (normal faults). The fault data is obtained from Giri et al. (2024). The study area is highlighted and elaborated in Fig. 2(a). The middle panel shows the earthquake focal mechanisms, scaled by the size and coloured according to the centroid depth (Wimpenny & Watson 2020). The bottom panel shows the gridded population density data across the entire extent (SEDAC 2017), intermontane basins are highlighted.

The extent of Himalayan ranges showing the interplay between topography around intermontane basins, seismicity and population. The top panel shows nine major intermontane basins. Major thrusts across the whole extent are also highlighted which include MFT: Main Frontal Thrust, MBT: Main Boundary Thrust and MCT: Main Central thrust. Dashed lines represent extensional features (normal faults). The fault data is obtained from Giri et al. (2024). The study area is highlighted and elaborated in Fig. 2(a). The middle panel shows the earthquake focal mechanisms, scaled by the size and coloured according to the centroid depth (Wimpenny & Watson 2020). The bottom panel shows the gridded population density data across the entire extent (SEDAC 2017), intermontane basins are highlighted.

Published in #GJI Geophysical Journal International: "Influence of surrounding topography on earthquake ground motions in intermontane basin settings: insights from the Kathmandu basin", Agrawal et al. Read the paper at academic.oup.com/gji/article/... @royalastrosoc.bsky.social @academic.oup.com

22.12.2025 07:27 πŸ‘ 5 πŸ” 2 πŸ’¬ 0 πŸ“Œ 0
Meridonial cuts of the kinetic energy density in dimensionless units of the waves indicated with a star (a), square (b) and circle (c) in Fig.3 Light regions indicate higher kinetic energy, while dark regions indicate lower kinetic energy.

Meridonial cuts of the kinetic energy density in dimensionless units of the waves indicated with a star (a), square (b) and circle (c) in Fig.3 Light regions indicate higher kinetic energy, while dark regions indicate lower kinetic energy.

Published in #GJI Geophysical Journal International: "The influence of a stably stratified layer on the hydromagnetic waves in the Earth’s core and their electromagnetic torques", Seuren et al. Read the paper at academic.oup.com/gji/article/... @royalastrosoc.bsky.social @academic.oup.com

12.12.2025 08:25 πŸ‘ 7 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0

That’s very sweet of you, @hughpumphrey.bsky.social, thank you very much for advertising this!

07.12.2025 15:43 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Thanks Hugh! And thanks again for letting me trial this in your course, and for doing the feedback! 🀩

01.12.2025 22:46 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

I have found out that the old link didn’t work anymore - not sure what happened there…

Read our blog here!

www.timeshighereducation.com/campus/make-...

01.12.2025 13:01 πŸ‘ 2 πŸ” 0 πŸ’¬ 0 πŸ“Œ 2
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Empower the student voice by making feedback a conversation Nurture feedback literacy through collaborative evaluation. Frederik Dahl Madsen and Kay Douglas show how a new approach works in two contrasting courses

Very excited that our blog on assessment feedback has now been picked up by @timeshighered.bsky.social !

27.11.2025 11:17 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 1

Well done @foteiniderv.bsky.social !

25.11.2025 12:05 πŸ‘ 2 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0

Well said, Natalia! πŸ‘πŸΌ

25.11.2025 12:03 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

That's my abstract submitted to #EGU26! πŸŽ‰

21.11.2025 13:37 πŸ‘ 1 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
Dr James O'Donoghue speaks to the audience at the Early Careers Event.

Dr James O'Donoghue speaks to the audience at the Early Careers Event.

Dr Affelia Wibisono discusses science communication.

Dr Affelia Wibisono discusses science communication.

Thanks to everyone who has joined us in person and online for our Early Careers Event. πŸ‘

It's been a hugely successful day!

This afternoon saw several speakers, including @interplanetary.bsky.social and Dr Affelia Wibisono, talking about their experiences in science communication. πŸͺπŸ”­πŸ—£οΈ

14.11.2025 15:42 πŸ‘ 12 πŸ” 2 πŸ’¬ 1 πŸ“Œ 0

We were super grateful to have you today, Chris! Thanks for coming along and sharing your wisdom and good advice β˜ΊοΈπŸ™πŸΌ

14.11.2025 18:53 πŸ‘ 1 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0

What a lovely session we had this morning!!

14.11.2025 13:56 πŸ‘ 3 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
Contact | Edinburgh Student Journal of Science

I am surprised they're not on Bluesky yet, but I am sure that will come soon!

If you're interested in getting your university involved with the journal, do reach out to Jack, the principal contact. His contact details are found through here: journals.ed.ac.uk/esjs/about/c...

13.11.2025 11:31 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
Edinburgh Student Journal of Science

If you haven't come across the #ESJS yet, it's an @edinburghdiamond.bsky.social hosted journal, specifically designed for undergraduates to publish their science, and for PhD students to gain experience in reviewing!

It's open to most universities in central Scotland, but is growing fast!

13.11.2025 11:29 πŸ‘ 0 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
Hilbert-Huang Transform Analysis of Intradecadal Variations in the Length of Earth's Day | Edinburgh Student Journal of Science

Very pleased to see Isobel's article on Length-of-day published in the Edinburgh Student Journal of Science #ESJS. πŸ•°οΈπŸŒπŸŽ‰

This was my first experience in independently supervising an undergraduate project, and I must say I am very proud of what my students achieved!

journals.ed.ac.uk/esjs/article...

13.11.2025 11:26 πŸ‘ 1 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0

It’s a beautiful place!

04.11.2025 15:30 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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An unexpected benefit to visiting aforementioned supervisor is the scenic post-lunch runs around West Kirby

04.11.2025 14:38 πŸ‘ 2 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0
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Despite train cancellations, I’m on my way to @liverpooluni.bsky.social to visit my geodesy-supervisor! Do quite enjoy working on the train these days

03.11.2025 08:38 πŸ‘ 3 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Do you need some WD40?

03.11.2025 08:31 πŸ‘ 0 πŸ” 0 πŸ’¬ 1 πŸ“Œ 0

Are you an early career researcher in geophysics or astronomy? Come to our event in London in two weeks!

01.11.2025 11:23 πŸ‘ 4 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0

Give my supervisor a listen, as he excellently explains the south Atlantic anomaly in the geomagnetic field 🧲 🌍 @bgs.ac.uk

01.11.2025 11:22 πŸ‘ 4 πŸ” 1 πŸ’¬ 0 πŸ“Œ 0
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Very excited to be at the #DeepDyn dynamos in a nutshell workshop at @mpsgoettingen.bsky.social !

The most exciting thing, of course, is to learn how to use the #MagIC dynamo code. 🌍

Second most exciting thing is having vegan currywurst for lunch! 🌭

28.10.2025 13:15 πŸ‘ 5 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0

Disclaimer: It feels like the post description doesn’t match the article, but it was the article I wanted to repost!

27.10.2025 18:25 πŸ‘ 0 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0
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Mosquitoes Discovered in Iceland for the First Time amid Rising Temperatures Bird flu surges and a government shutdown collide, complicating efforts to track cases and protect flocks.

Bird flu surges and a government shutdown collide, complicating efforts to track cases and protect flocks.

27.10.2025 14:20 πŸ‘ 64 πŸ” 17 πŸ’¬ 2 πŸ“Œ 1
Graphic promoting the 'Early Career Event' Specialist Discussion Meeting arranged by the Royal Astronomical Society.

Graphic promoting the 'Early Career Event' Specialist Discussion Meeting arranged by the Royal Astronomical Society.

πŸ§‘β€πŸ”¬ Are you an early career researcher?πŸ§‘β€πŸ”¬

If so, we'd love for you to attend our early career event next month. It will feature a careers panel, networking opportunities and a discussion about the importance of effective communication for sharing research.

Book your spot at: ras.ac.uk/early-career...

27.10.2025 13:07 πŸ‘ 6 πŸ” 5 πŸ’¬ 1 πŸ“Œ 0
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Cycling out and home from the @bgs.ac.uk Lyell Centre is a pleasure this time of year πŸŒˆπŸŒ…

22.10.2025 15:59 πŸ‘ 2 πŸ” 0 πŸ’¬ 0 πŸ“Œ 0