Josh Dean

Looks amazing, good luck in the field!

Bringing you today’s #bogbrunch from Svalbard - maybe permafrost picnic is more suitable? 🏔️🫧 @oxuniearthsci.bsky.social

#ch4 #co2

An algal bloom on a nutrient enriched lake encroaches into the Nymphaea alba and Chara hispida beds, causing plant dieback. Your work will develop a novel, targeted analytical method to allow us to rapidly screen samples to determine the molecular composition of the dissolved organic nutrients in these and other waters. These provide a critically important but overlooked nutrient resource driving ecosystem damage and biodiversity decline in waterbodies. We currently lack a unified technique that can rapidly screen samples in a targeted manner. You'll likely be highly motivated, enjoy both field and laboratory work, and be a good analytical chemist with attention to detail who is keen to make your mark through novel method development. Give Ian a ring or send him an e.mail (ian.d.bull@bristol.ac.uk), or contact me here or via my e.mail penny.johnes@bristol.ac.uk. We have a large team on the ERC REFRESH programme that you will be joining, along with two other PhD students due to start at the same time. Great team and learning opportunities.

‪Great opportunity: full @ukri.org funded PhD Studentship with 4 years fees, stipend (£19237 pa) and full Research Training Support Grant, working with Prof Ian Bull, Director of the National Environmental Isotope Facility and my
@ercrefresh.bsky.social team! Starts 10/2025 shorturl.at/AJREj 🧪

Earth Surface Geochemistry group members in Central Prague enjoying an evening after busy science 🧪 at the Goldschmidt Conference

Really fantastic @goldschmidt-confer.bsky.social #Goldschmidt2025 conference in Prague! Thanks @eageo.bsky.social

Some 🧪🥼⚒️ highlights #greenhouse gases in rivers & lakes; timescales of #water and element #storage in catchments; #enhancedweathering state of play; closing the geological #C budget.

We show that summertime CO2 and CH4 emissions from inland waters are an important component of lowland tundra carbon exchange with the atmosphere offsetting the terrestrial sink capacity. This is an important consideration for constraining future Arctic responses to climate warming

And that N2O inland water emissions were negligible compared to CO2 and CH4

We also found that a large flood pulse increased total landscape greenhouse gas emissions (and broke our eddy covariance tower...)

We found that inland waters (lakes, ponds and streams) offset the summer terrestrial carbon sink by about 9–13%

The Importance of Inland Water CO2, CH4, and N2O for Summertime Greenhouse Gas Exchange With the Atmosphere in Arctic Tundra Lowlands Integrating carbon emissions from inland waters into the carbon landscape exchange offset the summer terrestrial carbon sink by ∼9–∼13%. Carbon emissions from inland waters were higher during flo...

An incredible first paper by Melanie Martyn Rosco where we integrated inland water greenhouse gas emissions into the terrestrial carbon budget of a Siberian lowland tundra landscape: agupubs.onlinelibrary.wiley.com/doi/full/10....
Key findings and some cool field photos in the thread below!

Check out this guest post on our recent paper on river #carbon in @carbonbrief.org with @joshfdean.bsky.social

@oxuniearthsci.bsky.social @ox.ac.uk @erc.europa.eu

NEW – Guest post: How the world’s rivers are releasing billions of tonnes of ‘ancient’ carbon | @joshfdean.bsky.social @profbobhilton.bsky.social

Read here: buff.ly/QwWlF6N

Old carbon routed from land to the atmosphere by global river systems - Nature Using a global database of the radiocarbon content of rivers combining new and published measurements, isotopic mass balance suggests that about 60% of river CO2 emissions are derived from millennial ...

🌏Using a global database of the radiocarbon content of rivers, isotopic mass balance suggests that about 60% of river carbon dioxide from millennial or older carbon sources

Read the latest research article published in Nature by our former external editor, Joshua Dean
www.nature.com/articles/s41...

Old carbon routed from land to the atmosphere by global river systems - Nature Using a global database of the radiocarbon content of rivers combining new and published measurements, isotopic mass balance suggests that about 60% of river CO2 emissions are derived from millennial or older carbon sources.

Nature research paper: Old carbon routed from land to the atmosphere by global river systems

https://go.nature.com/3Sz8Jdn

Ancient carbon released through modern rivers A global analysis reveals that most carbon dioxide emitted by rivers derives not from modern plant material, as was thought, but from ancient, buried carbon.

A global analysis reveals that most carbon dioxide emitted by rivers derives not from modern plant material, as was thought, but from ancient, buried carbon

https://go.nature.com/3FQOdls

No advert out yet, but I will recruiting a 2yr postdoc, start date autumn 2025, at @livunigeog.bsky.social soon. Lowland and upland peatlands, GHGs, DOM and water chemistry. Plenty of fieldwork. Feel free to drop me a DM or email if you might be interested, and please spread the word.

Research shows rivers release ancient carbon dioxide into the atmosphere, uncovering a greater role for plants and soil in the carbon cycle A new study has revealed for the first time that ancient carbon, stored in landscapes for thousands of years or more, can find its way back to the atmosphere as CO₂ released from the surfaces of river...

An international team led by @joshfdean.bsky.social University of Bristol studied 700+ river sites across 26 countries.

The findings could reshape how we understand global #carbon emissions

Read more: bristol.ac.uk/news/2025/ju...

Dean et al. @nature.com reveals that most CO2 emitted by global rivers derives not from modern plant material, as was thought, but from ancient, buried carbon www.nature.com/articles/s41...

How & to what extent will the age of riverine CO2 + land C storage will change in the future?
rdcu.be/eprek

Research shows rivers release ancient carbon dioxide into the atmosphere, uncovering a greater role for plants and soil in the carbon cycle A new study has revealed for the first time that ancient carbon, stored in landscapes for thousands of years or more, can find its way back to the atmosphere as CO₂ released from the surfaces of river...

A new study from @joshfdean.bsky.social & @gemmacoxon.bsky.social has revealed for the first time that ancient carbon, stored in landscapes for thousands of years or more, can find its way back to the atmosphere as CO₂ released from the surfaces of rivers. Read more -> bristol.ac.uk/cabot/news/2...

New paper! led by Josh Dean “Old carbon routed from land to the atmosphere by global river systems”
doi.org/10.1038/s415...

#radiocarbon in #rivers reveals the age of CO2 they release to the atmosphere.

An active leak of old carbon from land.
🧪⚒️
@joshfdean.bsky.social @oxuniearthsci.bsky.social

This is the amazing #LadyParkWood. Could this be one of the “wildest” wood in the UK? Governed only by natural dynamics for >100 years. But where is the regeneration? Absent even in gaps. Ground flora too. Deer the main culprit, but grey squirrel too. #rewilding?

Wow, I never even heard about this! Ah well, I probably couldn’t have gone anyway with the little fella at home

New Job! Please repost!

We have a NERC funded PDRA position here @oxuniearthsci.bsky.social, 2 yrs, on modelling cryosphere change and hydrochemistry

#models, #carbon, #permafrost, #deglaciation

Come join our friendly team!

Apply by 11/06, any Qs get in touch!

my.corehr.com/pls/uoxrecru...

Scientists define the ingredients for finding natural clean hydrogen Researchers at the University of Oxford, Durham University and the University of Toronto have detailed the geological ingredients required to find clean sources of natural hydrogen beneath our feet. The work details the requirements for natural hydrogen, produced by the Earth itself over geological time, to accumulate in the crust, and identifies that the geological environments with those ingredients are widespread globally.

Researchers have detailed the geological ingredients required to find clean sources of natural hydrogen beneath our feet. These findings offer a solution to the challenge of hydrogen supply 🌏

Read the full story: www.earth.ox.ac.uk/article/scie...

A new peat map for England By Dr Ruth Waters, Director for Evidence, Natural England, and David Jones, Senior Responsible Officer for the Natural Capital and Ecosystem Assessment, Defra England’s peat deposits are one of our mo...

A positive step for #peatland #conservation in England - you can’t protect something you can’t measure 🗺️

naturalengland.blog.gov.uk/2025/05/12/a...

1/3: New paper: how do masting plants optimise the delay in reproduction? Having gaps (years) between reproductive events starves seed predators, increasing fitness. But they are also missed opportunities for reproduction. How do plants fine-tune the length of the time gaps to maximise fitness?

Sorry I can’t make it, I’m sure it will be interesting and good fun! I look forward to hearing what you covered down the line…

Thank you @michaelemann.bsky.social and @climatebook.bsky.social for this well written critique of ARIA's solar geoengineering research plans which are extremely risky and a huge distraction:

The Importance of Ditches and Canals in Global Inland Water CO2 and N2O Budgets We synthesized data across global climate zones to show, for the first time, that global ditches and canals emit notable amounts of carbon dioxide and nitrous oxide, at higher per area rates than pon...

📣 Our new study is out now! The importance of ditches and canals in global inland water CO2 and N2O budgets @globalchangebio.bsky.social @peatymike.bsky.social @jackiewebb.bsky.social onlinelibrary.wiley.com/doi/full/10....

We are seeking a Postdoctoral Researcher (PDRA) in Freshwater Ecosystem Ecology researching the role of organic matter as a nutrient resource in freshwater ecosystems. A 4.5 year role with great training opportunites in isotope ecology and mesocosm experimental science www.jobs.ac.uk/job/DLU610/p...

There's a postdoc in peatland biogeochemistry advertised on our project by Dolly Kothawala and Gustaf Granath
at Uppsala University. I can highly recommend Uppsala as a place to live and work.

www.uu.se/en/about-uu/...