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Stephen Roberts

@stever60.bsky.social

770 followers 770 following 57 posts

⚒️ 🧪Earth scientist / geologist reconstructing past environmental change mainly from lake sediments from Antarctica, Arctic, S. America, Nepal, UK and other places 🏡Cambridge, UK 🏳️‍🌈 he/him Instagram @antarctic_diary

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Stephen Roberts @stever60.bsky.social · Nov 18

Nearing the end of a month of fieldwork, collecting cores from Lake Tilicio (very cold) in the Annapurna Ranage and Lake Phewa (very warm) around Pokhara. It’s been eventful, inspiring, lots of fun, &, of course, stunningly beautiful. A huge thanks to all our Nepalese colleagues, friends and hosts!

Lake sediment coring rig on Lake Phewa in Pokhara - picture shows 4 happy researchers after a days’ work collecting multiple cores

Lake Tilicio in the Annapurna Range at 4500 m altitude - picture shows a Bianca Perren carrying a core collected from the lake back down in her rucksack looking out across the lake and majestic mountain range

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Stephen Roberts @stever60.bsky.social · 1d

Applications are now open for this years’ @iapetusdtp.bsky.social PhD projects … including this one investigating ice sheet and glacier history of the Sør Rondane Mountains in East Antarctica by developing in-situ 14C cosmogenic exposure dating methods - more here:

iapetus.ac.uk/studentships...

Black and white landscape photo of the Sør Rondane mountains in East Antarctica

Black and white photo of three people on top of the Utsteinen Nunatak in the Sor Rondane mountains in East Antarctica - some of the samples in this project were taken from this massif and its surrounding moraine

A black and white landscape photo of the Utsteinen Nunatak in the Sør Rondane mountains in East Antarctica taken while collecting cosmogenic exposure dating samples from the Teltet Nunatak

Black and white photo of two people walking across blue ice of the East Antarctic ice sheet surrounding the Sor Rondane mountains

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Reposted by Stephen Roberts

Keir Nichols @cosmokeir.bsky.social · 2d

Applications are now open for a Glasgow-based Iapetus DTP project centred on using in situ 14C to study glacier histories in East Antarctica! tinyurl.com/3ddvynn2 @stever60.bsky.social @uofglasgow.bsky.social @iapetusdtp.bsky.social @bas.ac.uk

A person standing on a moraine which is in front of a mountain. The mountain is in East Antarctica, with a small glacier between the mountain and moraine. The person is using a saw to collect a rock sample from the surface of a boulder on top of the moraine.

A photo taken from a mountain in East Antarctica, with moraines and blue ice in the foreground, and the vast East Antarctic Ice Sheet extending to the horizon. Some small mountains (nunataks) are poking out above the surface of the ice sheet at varying distances.

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Stephen Roberts @stever60.bsky.social · 2d

Applications are now open for this years’ BAS Iapetus PhD projects … including one working on our Big Thaw project investigating extreme precipitation in Nepal from sediment core and climate data - more details in this link @iapetusdtp.bsky.social @bas.ac.uk

iapetus.ac.uk/studentships...

Photo of Lake Tilicio in Nepal with an inset core showing our team collecting sediment cores from the lake

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Reposted by Stephen Roberts

Max Engel @drmaex.bsky.social · 18d

Collab of @stever60.bsky.social @bas.ac.uk @uniheidelberg.bsky.social #geography

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Reposted by Stephen Roberts

Max Engel @drmaex.bsky.social · 18d

After a solid week of lake coring and sampling for #storm and #tsunami deposits on the #Shetland Islands, we found this yet undocumented gem 💎 on northern Mainland - a distinct gravel layer inside the coastal dunes. Hoping for good OSL results 🤞🏽

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Reposted by Stephen Roberts

Max Engel @drmaex.bsky.social · 23d

Indeed, Loch Flugarth #ShetlandIslands is a beauty on the inside AND the outside! @stever60.bsky.social @uniheidelberg.bsky.social

Sand Voe bay connected to Loch Flugarth on northern Mainland in the Shetland Islands; photograph with a rainbow

Russian chamber corer with laminated lake deposits from Loch Flugarth

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Stephen Roberts @stever60.bsky.social · 21d

Lake coring in the Shetland Islands last week, looking for ancient tsunamis with @drmaex.bsky.social @uniheidelberg.bsky.social @bas.ac.uk

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Stephen Roberts @stever60.bsky.social · 22d

This is Fan Lake on Annenkov Island nr South Georgia - sediments from the top of the lake record were analysed with sediments from >400 lakes around the world to construct a new global temperature calibration model which can be used to reconstruct past changes in temperature over thousands of years

Stephen Roberts @stever60.bsky.social · 22d

See this link for more details

www.sciencedirect.com/science/arti...

Development of new global lake brGDGT-temperature calibrations: advances, applications, challenges, and recommendations

Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are a group of temperature-sensitive membrane lipids found in bacteria that have been widely …

www.sciencedirect.com

Stephen Roberts @stever60.bsky.social · 22d

Surface sediments from 400 lakes were analysed for biomarker compounds called branched glycerol dialkyl glycerol tetraethers (brGDGTs), a group of temperature-sensitive bacteria membrane lipids used in past temperature reconstructions - we expand calibration datasets, and evaluate calibration models

Map showing the location of over 400 lake sediment samples used in this new study

Stephen Roberts @stever60.bsky.social · 22d

New exciting new global lake sediment temperature calibration paper and dataset by @geochemem.bsky.social, including the first 5- and 6-methyl brGDGTs measured in lake sediments from Antarctica - eg Fan Lake. See link for details:
doi.org/10.1016/j.qu...

@bas.ac.uk @iapetusdtp.bsky.social

A map of the world showing the locations of over 400 lakes whose surface sediments were analysed for biomarker compounds called branched glycerol dialkyl glycerol tetraethers (brGDGTs) are a group of temperature-sensitive membrane lipids found in bacteria that have been widely used in palaeo-temperature reconstruction. The paper expands existing calibration datasets, and evaluates calibration models constructed using a range of statistical modelling approaches

A slide showing Fan Lake on Annenkov Island near South Georgia - sediments from the surface of a core taken from the bottom of the lake were analysed along with sediments from over 400 lakes around the world the construct a new global calibration model which can be used to reconstruct past changes in lake sediments over thousands of years

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Stephen Roberts @stever60.bsky.social · 23d

Second Scottish lake coring adventure of the summer … this time up to the Shetland Islands looking for ancient storms and tsunamis in lake sediments with @drmaex.bsky.social

Coring on Loch Flugarth north mainland Shetland - photo taken by Susie who lives in the house on the far right of this view of the loch looking at hills in the distance with a white houses

3 people in a small red boat on Loch Flugarth

View of Loch Flugarth from a large boulder with a rope tied to it towards some hills in the distance

A picture of the farm cat who lives near to Loch Flugarth

Reposted by Stephen Roberts

Huw Griffiths @huwiceandstuff.bsky.social · Aug 21

My whale photo got shortlisted in the Royal Society of Biology @rsb.org.uk ‬ Photographer of the Year competition. It is of a whale's chin! Do me a favour and give it a vote here and check out the other amazing photos: www.surveymonkey.com/r/T23CPZC
@bas.ac.uk

the underside of a humpback whale chin sticking out of the ocean. It is covered in barnacles

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Stephen Roberts @stever60.bsky.social · Jun 28

And a big thanks to our ‘special guest stars’ Tom Bradwell and Eileen Tisdall from University of Stirling and Nicola Dakin from @bgs.ac.uk for all their help

Morning tea at SCENE with Colin Adams, Iain Geldard, Jodie Geldard, Eileen Tisdall, and Tom Bradwell sat around a table in the common area

Colin Adams and Tom Bradwell inflating the raft on the beach at SCENE

Ellen Tisdall carrying a core back to shore along the boat jetty at the end of days’ coring

Stephen Roberts @stever60.bsky.social · Jun 28

A huge thanks to everyone at @sceneuog.bsky.social for hosting us - in particular Prof. Colin Adams for his phenomenal support, & Iain Geldard - we couldn’t have done it without both of you! Jodie Geldard did an amazing job organising the whole trip as part of her @iapetusdtp.bsky.social PhD

SCENE University of Glasgow research centre where we were based - photo shows the road leading up to the wooden building through the forest

Collection of sediment cores taken from Loch Lomond over the last 2 weeks strapped into the van for transport to BAS and Southampton for analysis as part of Jodie Geldard’s Iapetus DTP PhD with University of Stirling

Final day lunch at the oldest pub in Scotland, the Clachan with Colin Adams, Iain Geldard, Tom Bradwell, and Jodie Geldard (not in photo)

Selfie With Tom Bradwell outside the sign for the Clachan in Drymen, the oldest pub in Scotland (apparently)

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Stephen Roberts @stever60.bsky.social · Jun 28

Not everyday was like this but we had a couple of flat calm hot and sunny days out on the lake with stunning views across to Ben Lomond and surrounding mountains … which was very nice @iapetusdtp.bsky.social @bas.ac.uk

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Stephen Roberts @stever60.bsky.social · Jun 27

Some pictures from the last couple of weeks lake sediment coring on Loch Lomond with @iapetusdtp.bsky.social

Loch Lomond at sunset with coring rig moored in sheltered bay at SCENE university of Glasgow research centre

Loch Lomond view from the southern basin across to Ben Lomond

Collecting cores in the middle of Loch Lomond - 4 people capping a surface core retrieved for potential fish eDNA analysis

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Stephen Roberts @stever60.bsky.social · Jun 27

That's all for Loch Lomond coring: 12 cores collected in 10 days, 2 gravel layers reached and lots of very fine grey clay in between! @iapetusdtp.bsky.social @bas.ac.uk

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Stephen Roberts @stever60.bsky.social · May 31

Amazing sculpture exhibition Clearwell Caves in the Wye Valley

Sculpture of Red sunglasses in the foreground and orange high heeled shoes out of focus in the background

Sculpture of people holding hands in the shape of ladder

Reposted by Stephen Roberts

Iapetus DTP @iapetusdtp.bsky.social · May 23

We have just sent out the latest of Iapetus DTP's periodic newsletters. If it fell foul of your institution’s junk filter, read it here: eocampaign1.com/web-version?...

Iapetus news, May 2025

The latest news from Iapetus DTP

eocampaign1.com

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Reposted by Stephen Roberts

Iapetus DTP @iapetusdtp.bsky.social · May 14

Edinburgh looking fine on the first day of the Iapetus student conference 2025, funded by @ukri.org.

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Stephen Roberts @stever60.bsky.social · May 13

Early start … on my way to Edinburgh for the @iapetusdtp.bsky.social annual conference

Picture of my foot on Platform 4 Zone 5 at Peterborough station

Picture of the inside of the empty quiet carriage on the LNER train to Edinburgh

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Stephen Roberts @stever60.bsky.social · Apr 24

@iapetusdtp.bsky.social

Stephen Roberts @stever60.bsky.social · Apr 23

Iapetus Research experience placement (REP) projects are available for summer 2025 including one based @bas.ac.uk investigating the
Effects of Climate Change on the Polar Ionospheric F-region - see link for more details and eligibility criteria; deadline 12 pm 16/5/25

iapetus2.ac.uk/rep-projects/

A list of 5 REP research experience placements available for this summer

A picture of the thermosphere showing the F-region around the Earth

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Stephen Roberts @stever60.bsky.social · Apr 23

Stephen Roberts @stever60.bsky.social · Apr 22

Congratulations to all the editors for bringing everyone together and producing such a beautiful book, just in time for #Earthday - a big thanks to @oceanandice.bsky.social for keeping us all on track - really enjoyed being part of this!

British Antarctic Survey 🐧 @bas.ac.uk · Apr 22

Why is Antarctica so important?

Antarctica might feel very remote - until you look at the planet from a different perspective. It's actually central to our world's ocean currents.

🎁 Check the alt text to dig into this diagram

🌊 This is from a new book by BAS' @oceanandice.bsky.social (et al.)

The image shows a map of the world's currents, but looking at a projection of the world from the bottom of the globe, with Antarctica at its centre. The diagram shows all of the world's currents cycling through major oceans, all linked together by a central circular current that goes around the outside of the Antarctic continent.

"The Southern Ocean around Antarctica is central to global ocean circulation. It enables connectivity across the whole planet by linking the Atlantic, Pacific and Indian Ocean basins, and is the key site where waters are returned to the surface from depth and then converted into new water masses. The clockwise circulation of waters around Antarctica is the Antarctic Circumpolar Current, the strongest ocean current system in the world."

(Figure 1.1 from "Antarctica and the Earth System", edited By Michael P. Meredith, Jess Melbourne-Thomas, Alberto C. Naveira Garabato, Marilyn Raphael)

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