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David Olefeldt

@olefeldt.bsky.social

4.6K followers 290 following 55 posts

Professor in Catchment and Wetland Sciences at University of Alberta. Research on impacts of disturbances on function of northern peatlands, with focus on carbon cycling, greenhouse gas emissions, and on downstream water quality.

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David Olefeldt @olefeldt.bsky.social · Aug 28

New study where McKenzie Kuhn, I and co-authors show that accounting for differences among wetland and lake types is crucial for estimating current and future boreal-Arctic methane emissions – out now in Nature Climate Change.

www.nature.com/articles/s41...

Current and future methane emissions from boreal-Arctic wetlands and lakes - Nature Climate Change

How much methane will be emitted from the boreal-Arctic region under climate change is not well constrained. Here the authors show that accounting for distinct wetland and lake classes leads to lower ...

www.nature.com

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David Olefeldt @olefeldt.bsky.social · 18h

agupubs.onlinelibrary.wiley.com/doi/10.1029/...

The link in the first post doesn't seem to work yet, this should do it!

Large Carbon Losses From Burned Permafrost Peatlands During Post‐Fire Succession

Burned permafrost peatlands lost ∼130 g C m−2 yr−1 during the first four years post-fire Burned landscapes returned to a net carbon dioxide sink ∼15 years post-fire Net ecosystem exchange carbon...

agupubs.onlinelibrary.wiley.com

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David Olefeldt @olefeldt.bsky.social · 19h

The study was done on a peat plateau which burned in 2019. Christopher and our group managed to get together instrumentation and all in a few months to start measurements. Video below shows the site when we first arrived only a few weeks after the fire.

www.youtube.com/watch?v=REGX...

Steen River Burned Peatland site 2019

YouTube video by David Olefeldt

www.youtube.com

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David Olefeldt @olefeldt.bsky.social · 19h

So permafrost peatlands burn and they release lots of CO2 through combustion - but that's just the start. Christopher Schulze shows in a new GRL study that slow recovery causes continued CO2 losses in the following decade - overall similar in magnitude to the combustion!

doi.org/10.1029/2025...

doi.org

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David Olefeldt @olefeldt.bsky.social · Sep 4

New Study in ES&T! Permafrost peatlands accumulate mercury from distant sources, but thaw causes collapse into wetter bogs and fens. Lauren Thompson shows that these bogs, and especially fens, become hotspots for mercury methylation, and potential downstream transport.

pubs.acs.org/doi/10.1021/...

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David Olefeldt @olefeldt.bsky.social · Aug 28

Our analysis also reveals where effort should be placed to further improve estimates of boreal-Arctic wetland and lake methane emissions, including wintertime methane studies from wetlands, studies of lake methane ebullition, and further refined land cover maps.

David Olefeldt @olefeldt.bsky.social · Aug 28

Our estimate of current-day methane emissions is ~20-40% lower than many prior studies, partly because of a bias where prior studies were more likely to target sites with relatively higher emissions. Having new land cover maps with different wetland and lake types reduces this bias.

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David Olefeldt @olefeldt.bsky.social · Aug 28

This study uses data from almost 200 studies going back to the 1970s, with data from almost 2000 unique sites. Knowing what it takes to collect this data and publish these individual studies, it is humbling to be able to use their findings in a joint analysis – standing on the shoulder of giants.

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David Olefeldt @olefeldt.bsky.social · Aug 28

Our modelling of future methane emissions account for both climate warming (through a space-for-time framework) and permafrost thaw (through landscape transitions caused by thaw), and we find that these effects have important interactions – although the direct effect of warming dominates.

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David Olefeldt @olefeldt.bsky.social · Aug 28

Current and future methane emissions from boreal-Arctic wetlands and lakes - Nature Climate Change

www.nature.com

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Reposted by David Olefeldt

Donna Giberson (Elbows UP!) 🇨🇦🇺🇦 @donnag.bsky.social · Aug 23

Freshwater Ecology position!!! careers.ucalgary.ca/jobs/1652277...

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David Olefeldt @olefeldt.bsky.social · Aug 14

Perfect day for measuring carbon dioxide and methane emissions from our thawed (former permafrost) fen in northern Alberta. 20 deg C, light breeze and almost no mosquitoes.

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Reposted by David Olefeldt

Guido Grosse @grosseguido.bsky.social · Jul 28

The term “abrupt permafrost thaw” is increasingly used in the scientific literature. The concept comes with challenges as authors look at “abrupt“ change with different perspectives on time scales, magnitudes, and impacts. Webb et al developed a new conceptual framework: doi.org/10.1007/s406...

A Review of Abrupt Permafrost Thaw: Definitions, Usage, and a Proposed Conceptual Framework - Current Climate Change Reports

Purpose of Review We review how ‘abrupt thaw’ has been used in published studies, compare these definitions to abrupt processes in other Earth science disciplines, and provide a definitive framework f...

doi.org

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David Olefeldt @olefeldt.bsky.social · Jul 20

CBC highlights the issue of greenhouse gas emissions from peatland fires in Canada.

www.cbc.ca/news/science...

Carbon emissions from Canada's wildfires are spiking. But that's not counting our vast peatlands | CBC News

A new government model to estimate peatland emissions and their impact on climate change could provide a new perspective on the problem — and spark new discussions about solutions.

www.cbc.ca

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Reposted by David Olefeldt

New Phytologist @newphyt.bsky.social · Jul 19

#TansleyReview: The challenging but unique eco-evolutionary aspects of #SphagnumMoss

@queenofpeat.bsky.social, et al. 👇

📖 nph.onlinelibrary.wiley.com/doi/10.1111/...

#LatestIssue

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David Olefeldt @olefeldt.bsky.social · Jul 18

We look at organic matter, nutrients, and mercury primarily. But also sediment and other aspects. Early results do not show major impacts of the fire, but this has been expected due to the continuing drought - we are on our toes to sample if wetter conditions flush the soils.

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David Olefeldt @olefeldt.bsky.social · Jul 17

The black lines are the roads which we collect water samples along - shown with the historical fire map you can see that ~half of this large region has burned in the last few years. There are community concerns about impacts of wildfires and permafrost thaw on water and traditional land use.

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David Olefeldt @olefeldt.bsky.social · Jul 17

I spent this week collecting river samples in northwestern Canada (Dehcho, Hay, and South Slave regions), an area the size of England with ~4,000 km of driving.

And so much of the landscape is burned - we drove hours and hours through charred forests. The last decade has been unprecedented.

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David Olefeldt @olefeldt.bsky.social · Jul 11

The bog gives and the bog takes. Liam Heffernan's PhD site, the Lutose thermokarst big - photos from 2015 and today 10 years later... Note the trees dying in the background due to permafrost thaw, and the growth of Sphagnum mosses covering our once proud boardwalk!

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David Olefeldt @olefeldt.bsky.social · Jul 7

I have a fully funded PhD position open for start in Jan or May 2026. Field work in peatlands of the Northwest Territories, with lab work to understand potential downstream mobilization of carbon, nutrients, mercury after thaw or wildfire. Reach out for more information, and please send on!

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David Olefeldt @olefeldt.bsky.social · Jun 26

When the Arctic burns, the soils thaw. How much and for how long? Anna Talucci compiled depth of thaw measurements from 157 sites, now published in ESSD. Main impact occurs 4-10 years after fire, but effects remain 20+ years. Key information to estimate losses of soil C!

doi.org/10.5194/essd...

Reposted by David Olefeldt

Jonny Ritson @jpritson.bsky.social · Jun 18

'We should restore peatlands to slow down the invading Russians' as an idea tells us a lot about the state we are in.

www.aeco.earth/blog/peatlan...

Peatlands as a natural defence: An innovative approach to Europe's security

Europe’s defence needs a rethink. Rewetting peatlands offers a low-cost, dual solution for security, climate action, and nature conservation.

www.aeco.earth

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Reposted by David Olefeldt

Prof. Vincent Gauci @gaucigauci.bsky.social · Jun 19

My perspective “Tree methane exchange in a changing world” is now out in @natrevearthenviron.nature.com rdcu.be/erF4j

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David Olefeldt @olefeldt.bsky.social · Jun 4

This new map provides a global view of the distribution of a multitude of aquatic ecosystems, including various wetlands. It's a pretty big step forward, and I look forward to seeing how it will be used e.g. to study wetland greenhouse gases.

essd.copernicus.org/articles/17/...

Mapping the world's inland surface waters: an upgrade to the Global Lakes and Wetlands Database (GLWD v2)

Abstract. In recognition of the importance of inland waters, numerous datasets mapping their extents, types, or changes have been created using sources ranging from historical wetland maps to real-tim...

essd.copernicus.org

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Reposted by David Olefeldt

Justine Karst 🇨🇦 @j-karst.bsky.social · May 16

We are looking for a Canada Excellence Research Chair (CERC) in Community Ecology, Biological Invasions, Allelopathy, and Plant-Soil Feedbacks.

Details here:

universityaffairs.ca/search-job/?...

Search Jobs - University Affairs

universityaffairs.ca

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Reposted by David Olefeldt

Pep Canadell @pepcanadell.bsky.social · May 13

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The new Global Methane Budget is now published, open access.

essd.copernicus.org/articles/17/...

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