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James Allan

@jamesallanatmos.bsky.social
681 followers 122 following 341 posts

Long haired atmospheric scientist at the University of Manchester and NCAS. Opinions my own.

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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 29/09/2026
Dr Ioana Colfescu and Dr Akshay Deoras from @ncas-uk.bsky.social were part of a recent expert roundtable about the impacts of El Niño on the UK for the Government Office for Science - providing accessible science advice for policymakers. ncas.ac.uk/ncas-researc... _ #earth-science #SciComm 🧪
ncas.ac.uk
NCAS researchers advise UK Government about El Niño impacts - NCAS
Two NCAS researchers were among experts invited to contribute to a recent Government Office for Science rapid report examining the impacts of El Niño on the UK.
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James Allan @jamesallanatmos.bsky.social · 25/09/2026
Thats... interesting.
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 15/09/2026
We are looking for a Head of Observations to lead and shape the future of NCAS’s atmospheric measurement and observational science capability. Apply by 12 October 2026: ncas.ac.uk/job-opportun... #earth-science #SciComm 🧪
ncas.ac.uk
Job Opportunity: Head of Observations - NCAS
We are looking for a Head of Observations to lead and shape the future of NCAS’s atmospheric measurement and observational science capability.
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 06/08/2026
Drought isn't just about a lack of rainfall. As the climate warms, higher temperatures increase evaporation and dry out soils more quickly, meaning droughts can develop faster, become more severe, and affect new regions. ncas.ac.uk/what-does-cl... #earth-science #SciComm 🧪
ncas.ac.uk
What does climate change mean for drought? - NCAS
Climate change is reshaping drought by increasing evaporation and drying soils faster, causing droughts to develop more quickly, become more severe, and affect new regions. Research shows that drought...
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 03/08/2026
With prolonged hot weather, and wildfires burning across parts of Europe and North America, we explain what these events mean for the climate: #earth-science #SciComm 🧪 ncas.ac.uk/what-do-wild...
ncas.ac.uk
What do wildfires mean for climate change? - NCAS
Wildfires contribute to climate change by releasing greenhouse gases and other pollutants into the atmosphere, and by triggering vegetation changes.
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James Allan @jamesallanatmos.bsky.social · 02/08/2026
Article about the wildfires I get quoted in. observer.co.uk/news/nationa...
observer.co.uk
‘One spark could reignite swathes of the country’: wildfi...
Wildfires are becoming a systemic seasonal threat, posing serious risks to health, homes and the natural world across the UK
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 29/07/2026
With prolonged hot weather, and wildfires burning across the UK and Europe, what does this mean for air quality in the affected areas or places downwind? ncas.ac.uk/what-do-wild... #earth-science #SciComm 🧪
ncas.ac.uk
What do wildfires mean for air quality? - NCAS
Wildfires can have significant impacts on air quality, as wildfire smoke contains a mixture of hazardous air pollutants.
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 28/07/2026
Saharan dust pollution in Europe is increasing, with implications for both public health and solar energy. #earth-science #SciComm 🧪 ncas.ac.uk/desert-dust-...
ncas.ac.uk
Desert dust pollution in Europe is rising, with risks for health and solar energy - NCAS
The amount of desert dust from North Africa that is reaching Europe is on the rise, with implications for health and for solar energy.
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James Allan @jamesallanatmos.bsky.social · 29/07/2026
OK, I normally don't like to talk politics on BlueSky, but this does for me highlight an important point. Discussions about what the power grids can and can't handle are a lot more complicated than many people with strong opinions are willing to concede.
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James Allan @jamesallanatmos.bsky.social · 16/07/2026
While the supersite has been doing loads of measurements of the current wildfires, here's another example of its use, helping to quantify the increasing prevalence of desert dust in Europe in this Swiss-lead study. @manchester.ac.uk @ncas-uk.bsky.social www.manchester.ac.uk/about/news/m...
manchester.ac.uk
Manchester air quality data helps reveal growing health and energy risks from Saharan dust
Data collected at The University of Manchester's Air Quality Supersite has contributed to a major international study showing that increasing amounts of desert dust from North Africa are reaching Euro...
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James Allan @jamesallanatmos.bsky.social · 14/07/2026
The reason is shown by our ceilometer, which uses a laser to see pollution above us. Here it shows that for some of the time (e.g. between 5 and 10am this morning), the smoke was mainly drifting about 500m above us, but after that it started mixing downward and affecting people on the ground. (2/2)
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James Allan @jamesallanatmos.bsky.social · 14/07/2026
Update on the fires at Manchester. Some people (like me) might be wondering why the smell has been coming and going, but all the while the sky has been persistently hazy. Our instruments see this as well, here showing PM coming and going. (1/2) whitworth.cas.manchester.ac.uk/live/firs/ae...
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James Allan @jamesallanatmos.bsky.social · 14/07/2026
That looks very wildfire-y to me.
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James Allan @jamesallanatmos.bsky.social · 13/07/2026
Yeah, I confess that I'm being a bit Manchester-centric because I'm trying to understand the readings that we're getting at the moment.
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James Allan @jamesallanatmos.bsky.social · 13/07/2026
Holy Moly, it seems the plume affected Liverpool. Source: uk-air.defra.gov.uk/data
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James Allan @jamesallanatmos.bsky.social · 13/07/2026
A satellite picture from yesterday showing how the fires have been influencing Manchester. Note it's not affecting the whole are at the same time, which is why the smell has been coming and going all day. Source: NASA Aqua/MODIS true colour reflectance 12/07/2026, worldview.earthdata.nasa.gov
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Reposted by James Allan
Dr Gary Fuller @drgaryfuller.bsky.social · 13/07/2026
Estimated 2,700 people died early in the UK in the May and June heatwaves. Research led by Clair Barnes @imperial.ac.uk Piece by @dpcarrington.bsky.social. www.theguardian.com/environment/...
theguardian.com
June heatwave killed up to 440 people a day in England and Wales, data suggests
Extreme temperatures in May and June led to about 2,700 lost lives in total with climate crisis adding 3C to 4C
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James Allan @jamesallanatmos.bsky.social · 13/07/2026
We'll need to look at this carefully, of course, but the PM2.5 composition is looking very consistent with wildfire smoke, with a very high organic and black carbon content. (2/2)
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James Allan @jamesallanatmos.bsky.social · 13/07/2026
Last night's data from the Manchester Air Quality Supersite. We had some serious influence from the fires. (1/2) whitworth.cas.manchester.ac.uk/live/firs/ae...
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James Allan @jamesallanatmos.bsky.social · 12/07/2026
Wow!
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James Allan @jamesallanatmos.bsky.social · 12/07/2026
Unfortunately the archive plot feature doesn't appear to be working. That website is long overdue an upgrade!
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James Allan @jamesallanatmos.bsky.social · 12/07/2026
Think we're seeing the emissions from the nearby Dovestone moorland fire at the Manchester supersite. That's pretty nasty! whitworth.cas.manchester.ac.uk/live/firs/ae...
Graphs showing black carbon and nonrefractory particulate matter in Manchester for 12 July 2026
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Reposted by James Allan
Dr Gary Fuller @drgaryfuller.bsky.social · 03/07/2026
"Seventy years after the Clean Air Act, the lessons are clear. Disasters should not be required to trigger action. The Great Smog forced change. But policy should anticipate risk, not respond to tragedy." - Ian Williams on the Clean Air Act. theconversation.com/70-years-on-...
theconversation.com
70 years on from the killer smog: what clean air laws teach us about power, pollution and profit
Economic interests have shaped society’s response to pollution. Now, policy needs to align with the scientific evidence to clean up our air.
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Reposted by James Allan
Met Office - weather and climate @metoffice.gov.uk · 06/07/2026
Yesterday marked 70 years since the UK Clean Air Act 1956 - the first national legislation to tackle air pollution, introduced in response to the devastating Great Smog of London in 1952. The graphic below is courtesy of airqualitystripes.info. 🧵 1/5
Alt text: Graphic shows London’s particulate matter air pollution (PM2.5) concentrations from 1850 to 2022. Concentrations rose overall up until 1960s and then declined rapidly. 

Title says: what do the air quality stripes tell us about London's air quality? Text at bottom of graphic says: for more information visit www.airqualitystripes.info. The graphic highlights the 1952 Great Smog event when air pollution levels were poor. It also mentions the introduction of the UK Clean Air Act. Additionally, it says from the 1960s to 2026 there was increased legislation and a shift to cleaner technologies, leading to improvements in air quality.
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 03/07/2026
The Data Integration Model for Air Quality underpins the @who.int assessment of global air pollution trends and inequalities. Find out about the latest update from NCAS’s Dr Matthew Thomas: ncas.ac.uk/ncas-air-qua...
Busy street with lots of people walking, riding scooters, and driving cars and trucks.
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
To be clear, this paper is about physical science, not about advocacy in any direction. I don't intend to comment on anyone else's personal opinions here.
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
This used data from a variety of sources with varying quality, to try to get a comprehensive assessment. Bottom line is that while progress has been made over the years, in the last 5 years this progress seems to have slowed in middle- and low-income countries. (2/2) www.who.int/news/item/29...
who.int
New SDG data shows stalled progress on air pollution and health
The release of data on ambient and household air pollution highlights critical inequalities: while fine particulate matter (PM2.5) levels dropped globally until 2020, they have since remained largely ...
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
This is a major WHO air quality evaluation exercise that a @manchester.ac.uk/ @ncas-uk.bsky.social colleague of mine (Matthew Thomas) contributed to. (1/2) www.manchester.ac.uk/about/news/u...
manchester.ac.uk
University of Manchester research supports major WHO update on global air pollution
A researcher from The University of Manchester has contributed to a major World Health Organization (WHO) update revealing that global progress on reducing air pollution has slowed, with low- and midd...
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
There's a lot to unpack, and I was going to write a summary of it here. But let's wait for it to get past peer-review first! I'll maybe write more once it has. Also, stay tuned for more papers in due course. (4/4)
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
What we did here was go into the nitty-gritty of this, using a suite of research instrumentation to measure emissions in real time and probe what was driving the various pollutants. A key theme is in user behaviour, in particular how much fuel is loaded and when. (3/4)
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
One of the main themes of this work relates to previous observations made regarding emissions from the modern 'Ecodesign' stoves where emissions of certain pollutants can be non-optimal, in particular when used with very dry fuels. (2/4) uk-air.defra.gov.uk/library/repo...
uk-air.defra.gov.uk
Report: Emission Factors for Domestic Solid Fuels Project - Work Package 3 Report - DEFRA UK Air - GOV.UK
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James Allan @jamesallanatmos.bsky.social · 30/06/2026
Some of our recent stove work is now out there, albeit in preprint. I don't normally advertise work until it's passed peer-review, but people have been bugging me about it. Paper is by Zixuan, a PhD student of mine who is graduating soon. (1/4) ar.copernicus.org/preprints/ar...
ar.copernicus.org
Mixing state of Carbonaceous Aerosol Emissions from an Ecodesign Woodstove
Abstract. Residential wood burning (RWB) has become an increasingly significant source of carbonaceous aerosols (CAs) in the UK and worldwide. Black Carbon (BC) and Organic Aerosol (OA) fractions of C...
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James Allan @jamesallanatmos.bsky.social · 25/06/2026
These chemistry-driven secondary pollution episodes are among the less well understood aspects of air quality and therefore harder to predict. But as episodes like the current one become more common, we will need to study these and the underlying processes further so we can best prepare. (6/6)
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James Allan @jamesallanatmos.bsky.social · 25/06/2026
These can contribute massively to ultrafine particles, which is a strong area of interest. These can penetrate into the bloodstream and potentially cause more damage, but we lack decent data on. This is the red line on the graph below. (5/6)
Graph of particle number vs time in Manchester
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James Allan @jamesallanatmos.bsky.social · 25/06/2026
But going back to particulates, we can also see interesting stuff going on with the very small particles. The white splotch on the bottom right hand corner is likely new particle formation, again driven by chemistry. (4/6)
Size distribution data from Manchester, showing activity in the smaller sizes
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James Allan @jamesallanatmos.bsky.social · 25/06/2026
Also ozone was high. If you convert ppb to µg m-3 (approximately double it), we maybe hit the WHO guideline limit of 100 µg m-3 over an 8-hour mean. (3/6)
Graph of ozone concentrations from Manchester.
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James Allan @jamesallanatmos.bsky.social · 25/06/2026
But I actually started drafting that article a few days ago, so I couldn't use any actual data from the current heatwave. So here it is now taken from whitworth.cas.manchester.ac.uk/live/firs/. As predicted, in Manchester we have particulate matter dominated by organics (2/6)
Graph of particulate matter composition, with organics dominant
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James Allan @jamesallanatmos.bsky.social · 25/06/2026
I did an article for NCAS explaining how heatwaves can bad for air quality as well as all the other problems they come with. The short version is with all the chemistry going on and air arriving from the continent, they are especially bad for PM and ozone. 🧵(1/6)
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 18/06/2026
If you'd like to learn more about air pollution and its links to people's health and global climate, check out this list of our recent and ongoing research: #CleanAirDay @globalactionplan.bsky.social #earth-science #SciComm 🧪
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James Allan @jamesallanatmos.bsky.social · 22/06/2026
This is the bit that should be very concerning: "Météo-France said of the 51 heatwaves recorded in France since 1947, 34 have taken place since 2000 and 26 since 2011."
bbc.co.uk
Schools close as more than half of France under red heat alerts
The health minister warns many citizens "will suffer", with temperatures set to peak on Monday.
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James Allan @jamesallanatmos.bsky.social · 19/06/2026
OK, not atmospheric science, but I did used to teach biogeochemical cycling and had to bone up on the phosphate cycle in the process. This is really kind of interesting.
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James Allan @jamesallanatmos.bsky.social · 19/06/2026
🚨New paper!🚨 Well, it's not that new, but I was waiting for a proper citation before I made a big deal about it. This one's another paper from one of my students, this one looking at trends of metals in particulates over the lockdown period at the Manchester Supersite. doi.org/10.1021/acse...
doi.org
PM10 Contributions from Construction, Biomass Burning, and Nonexhaust Traffic Emissions at the UK Urban Background Site, Based on Online Metals Data
Atmospheric trace metals in particulate matter (PM) pose significant environmental and health risks, making their study crucial for understanding urban air quality. These metals originate from various...
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 18/06/2026
This #CleanAirDay, research from @ncas-uk.bsky.social highlights how understanding air quality across different settings can help protect health and support better decisions for communities across the UK and beyond. ncas.ac.uk/clean-air-da... #earth-science #SciComm 🧪
ncas.ac.uk
Air quality research links people, places and health - NCAS
This Clean Air Day, NCAS highlights how understanding air quality can help protect people and support better decisions.
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Reposted by James Allan
National Centre for Atmospheric Science @ncas-uk.bsky.social · 10/06/2026
Airports drive growth and connectivity, but their pollution can harm nearby communities. Prof Ally Lewis highlights the health impacts of airports on local residents in a report for POST. Read our summary: ncas.ac.uk/air-pollutio... #earth-science #SciComm 🧪
ncas.ac.uk
Air pollution from airports matters to local communities - NCAS
Professor Alastair Lewis talks about airports, air pollution, health, regulation, and the role of atmospheric scientists.
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James Allan @jamesallanatmos.bsky.social · 02/06/2026
"None of the predictions of scientists have come true." Actually, they have. Svante Arrhenius actually predicted warming in response to fossil fuel burning at the tail end of the 19th century. More recently, the IPCC predictions actually proved quite reliable. www.forbes.com/sites/jimfoe... (8/8)
forbes.com
From Forecast To Fact: What 1990s Climate Models Got Exactly Right
In the 1990s, climate scientists made bold forecasts about carbon, heat, and storms. Read what science predicted and what leaders can learn for the future.
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James Allan @jamesallanatmos.bsky.social · 02/06/2026
"This is all natural because we're coming out of an ice age." The cycles that drive the interglacial periods are very predictable and take place over tens of thousands of years, not decades, which is what's happening now. science.nasa.gov/science-rese... (7/8)
science.nasa.gov
Why Milankovitch (Orbital) Cycles Can't Explain Earth's Current Warming - NASA Science
In the last few months, a number of questions have come in asking if NASA has attributed Earth’s recent warming to changes in how Earth moves through space
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James Allan @jamesallanatmos.bsky.social · 02/06/2026
"They changed the name from global warming to climate change." This one's partly true as far as the media is concerned, but ask them when they thought the name change occurred, and I'll bet the year they give is long after the convening of the Intergovernmental Panel on Climate Change. (6/8)
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James Allan @jamesallanatmos.bsky.social · 02/06/2026
"We never heard anything about global warming until the 1990s" I've heard this in the context of it being a post-cold-war-communist conspiracy. It's been studied for well over a century now, and a landmark was Jim Hansen's 1988 testimony to congress, which was before the Belin Wall fell. (5/8)
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James Allan @jamesallanatmos.bsky.social · 02/06/2026
"The Antarctic/Arctic is gaining ice." No it isn't. There was a story about a particular part of the Antarctic unexpectedly gaining ice a while back, but this has morphed in the heads of many to apply universally to both poles. Which isn't supported by any data. nsidc.org/sea-ice-today (4/8)
nsidc.org
Sea Ice Today | National Snow and Ice Data Center
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James Allan @jamesallanatmos.bsky.social · 02/06/2026
"They said we'd all be underwater by now." No they didn't, unless you're talking about the film Waterworld, which wasn't exactly grounded in reality. The 1990 IPCC report predicted a rise of 20cm by 2030, which wan't too far off the mark. weather.metoffice.gov.uk/climate-chan... (3/8)
weather.metoffice.gov.uk
Past and future sea level rise
Causes of sea level rise and what we do and don't know for the future
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