Project NuClim

Photo of a group of five people standing behind a long metall box about half the height of the people. The people seem to be discussing something with one woman pointing towards the direction of the camera. In the background the sea and a stony shore is visible. On the horizon the grey of the sea and sky are merging.

We’re excited for this next step in strengthening Mace Head’s contribution to global
atmospheric science, stay tuned for more updates!

The addition of the ANSTO 1500-L Radon Monitor plays a key role in classifying background air masses, offering valuable insights into regional and global greenhouse gas dynamics at the historically significant Mace Head Atmospheric Research station.

Photo of a grey, cloudy sky above brown-green and stony landscape. In the front of the picture, two blue boxes, a backpack, two blue barrels and other unidentifiable objects are placed.

Photo of the inside of some big metal box with many cables, tubes and a little rack on the right side. In the lower left corner a grey big barrel is labelled "Filter". The whole box is wrapped in some purple-red plastic cover and sits on transport pallet.

We’re happy to announce that the radon monitor upgrade arrived last week at @maceheadccaps.bsky.social.
This marks an exciting milestone in our efforts to characterize background air masses and improve understanding of greenhouse gas sources and transport.

Text/Photo: Aimon Tanvir

👁️‍🗨️ Enroll for free for this 3rd edition of the ATMO-ACCESS #MOOC to learn more about Atmospheric Research Infrastructures
🔗 www.fun-mooc.fr/en/courses/a...
📅 Starting Nov 3rd, 2025
⏳ Duration: 5 hours over a period of 2 weeks

@actris.bsky.social @icos-ri.eu @iagos-ri.bsky.social @envri.bsky.social

#EGU26 is already on its way 🎉!
Abstract submissions are officially open until 15 January 2026, 13:00 CET.

Let the journey begin and submit your abstract NOW!

👉 Visit https://www.egu26.eu/ for more information!

Final reminder - call for session proposals for ICOS Science Conference 2026 closes this Friday 24th October 2025 at noon (12:00 CET)!

Submit your proposal here: www.icos-cp.eu/news-and-eve...

#ICOS2026SC

Don’t miss Prof. Trude Storelvmo’s talk on Arctic mixed-phase #clouds, connecting insights from small-scale processses to large-scale #climate impacts. 🌍☁️
📆 Wednesday 29 Oct at 1pm (CET) on Zoom! epfl.zoom.us/j/6156668523...

Learn more about the NuClim project at www.nuclim.eu and about Mace Head station on their website www.macehead.org

For us, Mace Head is an opportunity to measure the greenhouse gas background in marine and terrestrial air masses and determine a greenhouse gas baseline. For this, we will upgrade the radon monitoring system. This will improve the detection of gradients in greenhouse gas levels and climate models.

Mace Head Atmospheric Research Station has one of the longest datasets of aerosol measurements in the world, and is the longest such dataset in Europe.

This is an opportunity to study clean background air of the Northern hemisphere westerlies and its atmospheric composition in terms of greenhouse gases and short-lived climate forcers. When easterly air masses arrive, they enable the evaluation of continental outflow and polluted air outflow.

Photo of two small buildings on a green, stony field with blue sky and some scattered clouds. The huts are surrounded by a green metallic fence. Between the two huts a white container is placed and on top and next to them a number of antennas are visible.

The Atmospheric Research Station at Mace Head @maceheadccaps.bsky.social ist located on the west coast of Ireland (Carna, County Galway). It offers a unique exposure to westerly winds coming from the North Atlantic Ocean into Europe.

Text/photo: Aimon Tanvir

Photo of a white and black coffee machine on a beige counter. The machine is very round overall with a circular cut-out to place the cup and an apparently half-cylinder shape for the main body.

A scientist’s best friend when setting up equipment for field measurements is the coffee machine ...

Photo: Scott Chambers

Air that has only been over the Atlantic Ocean for more than two weeks can help to tell us the background concentrations of greenhouse gases in air arriving in Europe, and therefore offer important information for research, regulation and monitoring.

In NuClim, we will use the radon concentration in the air measured at Graciosa and @maceheadccaps.bsky.social to characterise how much the air reaching the stations has been recently influenced by land, or whether it has spent a long time just over the ocean.

Since most sources of pollution are also on land, just measuring the radon in air at remote sites in the ocean can tell us how likely it is that the air contains other pollution. Or how long the air has been away from any large pollution sources and is behaving like “background” air.

Together, these two properties mean that by just measuring radon, we can get some very interesting information about the air: mainly, in the past few weeks, how long has this particular bit of air spent over land.

As a gas, radon mixes with the air and is moved by wind. It has a half-life of about 3.8 days, so after 3.8 days half of the radon that came out of the ground will have disappeared. After 2 or 3 weeks, there is almost none left at all!

Radon is a naturally occurring radioactive gas. It originates nearly completely from land because it is created by the decay of naturally occurring radium in rocks and soils. As there is very little radium in suspended ocean sediments, not much radon comes from the oceans.

The figure is a two-part drawing. The main colors are different shades of blue and a dark orange. The top part is titled "Radon originates from land". In it many arrows are moving from left to right. They have the same color dark orange color as "radon" in the title. They are on top of symbols for wind. Some arrows end, some start but overall the number at each horizontal position remains the same. On the bottom, arrows seem to originate from a dark blue rectangle in the same color as "land" in the title. In addition, on it are placed little icons showing an industrial facility. On the right side of the figure, a location marker is set into the air. In it, a a scale indicates a high value and it says "radon" below the scale. The bottom part is titled "Radon disappears over sea". The overall layout of the second part is very similar to the first. However, the right two thirds of the bottom do not have the rectangle but waves in a lighter blue (the same color as "sea" in the title). From it only very few and small arrows originate. The arrows in the air are similar to the previous ones on the left side, on the right side however, there are fewer arrows beginning, so the overall number of arrows decreases. The scale in the location marker shows a low value.

How does radon tell us about how air moves and mixes?
And what is the goal of our project?

Next round of lectures for the 7th @eumetsat.int @esa.int @ecmwf.int @copernicusecmwf.bsky.social Joint Training on Atmospheric Composition are tomorrow (9 Oct, CEST):

10:00 Alex Hoffman on EarthCARE observations
14:00 Viktoria Sofieva on stratospheric aerosols

eumetsat.zoom.us/meeting/regi...

Don’t miss this week’s online lectures at the 7th Joint Training Course on Atmospheric Composition hosted by @ecmwf.int, CAMS, @eumetsat.int and @esa.int (9–10 Oct 2025). Lectures are open to all and cover instruments & data, aerosol modelling & monitoring, ML applications and more.

Photo of a donkey amidst dry grass and brown earth. The donkey seems to be walking and looks into the camera. In the background some green shrubs and the sea are visible. The sky is blue with some scattered clouds.

Photo of two white goats between grass and shrubs. The goats stand behind each other. The goat further away looks directly into the camera, the other one to its right side.

At Graciosa, the daily commute on foot to the ARM station always included extra time to pat the goats and donkey.

Photos: Scott Chambers

Hello from the ICOS Atmosphere station Mace Head in Ireland! 👋 Our crew visited this unique coastal site, where some of the cleanest Atlantic air is measured, to film for the #ExploreICOS series. Stay tuned!

Learn more about the station: icos-cp.eu/news-and-eve...

Learn more on our website: www.nuclim.eu

A map in shades of blue showing the North Eastern Atlantic with light arrows mostly from south west to north east and highlighting the Graciosa Island in the Azores and Mace Head in Ireland. A big cloud in the top left corner, containing the text "measurements of air masses without human influence". Around the text, icons for pressure, methane, gamma radiation, wind, carbon dioxide, particulate matter, carbon monoxide, eddies, ozone, rain, radon and temperature are arranged. The cloud is connected to the two measurement stations by a kind of flow-y triangle. In the top left corner the project's logo and two hands holding an earth and radiation sign in grey are placed. In the bottom right corner small text says: "Wind data from E.U. Copernicus Marine Service Information (DOI: 10.48670/moi-00181), map data from Natural Earth".

The first measurements are running and more will follow soon!
NuClim aims to determine the baseline of greenhouse gas concentrations in the North Atlantic. We look at radon, greenhouse gases and a range of other parameters at the ENA observatory (Azores) and @maceheadccaps.bsky.social (Ireland).

@inesctec.bsky.social is using the world’s most sensitive detector, the 1500 L ANSTO radon monitor, with a detection limit as low as 0.025 Bq·m⁻³, to collect high-precision radon observations, pushing the boundaries of atmospheric research and extending applications of nuclear measurements.

Had fun setting up the Cluster Ion Counter on top of a shipping container at the ENA ARM site as part of the NuClim campaign. Proud to see it operational and measuring concentration + mobility of positive & negative cluster ions in real time! @inesctec.bsky.social @nuclim.bsky.social

Ready to start working on the installation of the radon detector and cluster ion counter at the ENA ARM facility in the Graciosa Island.

Ilmatieteen laitos käynnisti radonin ja kasvihuonekaasujen mittaukset Mittaukset tukevat ilmastotutkimusta ja auttavat parantamaan kasvihuonekaasupäästöjen arviointia.

Terveisiä Azoreilta! Graciosan saarella mitataan nyt radonia ja kasvihuonekaasuja osana NuClim-hanketta. Mittaukset tukevat ilmastotutkimusta ja parantavat kasvihuonekaasupäästöjen arviointia.

‪@nuclim.bsky.social‬

www.ilmatieteenlaitos.fi/uutinen/4Tdl...