John Marsham
johnmarsham.bsky.social
John Marsham
@johnmarsham.bsky.social
Prof of Atmospheric Science, Weather, Climate, Tropical Meteorology, Communicating the Climate Crisis
Pinned
A reminder for everyone to ask their MP to go to this. Politicians must know the facts on the threat & solutions. And crucially, they need to have been publicly seen to have been informed, so they can't say they didn't know.
I urge all policymakers to attend this vital briefing on the climate & nature crisis, which brings the latest science from leading experts straight to the people in power. I’d like to see one in every country, & the organizers are open to sharing the model. More info: www.nebriefing.org
National Emergency Briefing on climate & nature
An unfiltered assessment of the latest threats arising from the climate & nature crisis to an invite-only audience. Westminster Central Hall, 27 November. Has your MP confirmed yet?
www.nebriefing.org
Only 3 sleeps to go!

Not too late to ask your MP to attend if they have not signed up (Check via the website)

www.nebriefing.org
National Emergency Briefing on climate & nature
An unfiltered assessment of the latest threats to UK food supply, health and national security from eight leading experts to an invitation-only audience - also covering positive solutions. Westminster...
www.nebriefing.org
November 25, 2025 at 8:15 AM
Reposted by John Marsham
Open letter from over 1,000 UK scientists urging all MPs to attend the National Emergency Briefing. A huge list full of highly respected names.

"Without much more urgent and decisive action, we risk seeing these impacts overwhelm our capacity to respond."

Please share with your MP #NEB2025
National Emergency Briefing
An unfiltered assessment of the latest threats to UK food supply, health and national security from eight leading experts to an invitation-only audience - also covering positive solutions. Westminster...
www.nebriefing.org
November 23, 2025 at 6:14 PM
Reposted by John Marsham
We’ve been busy at #COP30 in Belém!
🌍 From carbon budgets to climate-resilient food systems, the University of Leeds team has been everywhere. Here’s what we’ve been up to 👇 (1/6)
November 21, 2025 at 3:09 PM
November 21, 2025 at 4:05 PM
Data driven ML nowcasting of imagery is complementary to nowcasts of derived quantities such as rain. Great work from Kilian Hermes - first dust nowcasts I'm aware of - and does storms. Diffusion - so large ensemble cheap to run. www.sciencedirect.com/science/arti...
Nowcasting of dust and convective storms via diffusion-model predictions of SEVIRI RGB imagery
Convective storms in the tropics are inherently unpredictable on the scales typical of global Numerical Weather Prediction (NWP) models. Rapid-refresh…
www.sciencedirect.com
November 20, 2025 at 3:18 PM
We are "turning the volume up to eleven". Our societies are not setup for this
Holy shit.

It is confirmed that Melissa had the 252mph hurricane winds taking the record from Typhoon Megi in 2010 with 248mph winds.

news.ucar.edu/133047/recor...
Record-breaking winds confirmed for Hurricane Melissa | NCAR & UCAR News
news.ucar.edu
November 19, 2025 at 8:19 PM
Unprecedented rain. We're taking our climate outside the range our entire agriculture & trade based human civilisation has grown up in.

I think this site is ~400 to 1800 AD. It wasn't built for this.

www.aljazeera.com/news/2025/10...
Record rains drive flooding in Vietnam, submerging ancient city
Vietnam's weather agency has recorded its highest level of rainfall for a 24-hour period in the historic city of Hue.
www.aljazeera.com
November 19, 2025 at 4:44 PM
"one of the bluntest warnings any Iranian leader has issued: without rain, Tehran may one day have to be evacuated."

"Tehran typically receives 50 to 60 millimeters of rain in October and November. This year it has had none, and forecasts offer little hope."
"The impact was dramatic. Water use fell by more than 55% in under two years, from 1.2 billion liters per day to about 500 million.When rains finally returned in 2018, the reservoirs refilled. But the deeper lesson endured: transparent, collective action can shift behavior on a massive scale"
Can Tehran use the Cape Town model to escape a water crisis 'Day Zero'?
As Iran’s capital Tehran endures its worst water crisis in living memory, few recent global cases offer clearer lessons than Cape Town in South Africa in 2018.
www.iranintl.com
November 19, 2025 at 2:24 PM
Great new work from Ben Maybee - teasing out processes by scale.
"When all sub-synoptic SM variability is homogenized, peak MCS counts drop by 23%", maintaining small-scale variability maintains primary initiation, reducing the drop in MCS totals.
agupubs.onlinelibrary.wiley.com/doi/10.1029/...
Homogeneous Soil Moisture Fields Suppress Sahelian MCS Frequency
Suppressing sub-synoptic soil moisture (SM) heterogeneity (< ${< } $1,000 km) decreases peak Mesoscale Convective System (MCS) population by 23%, without weakening convective intensity Mesoscale ...
agupubs.onlinelibrary.wiley.com
November 18, 2025 at 4:25 PM
Reposted by John Marsham
UK and Norway won nature's lottery in 1970 - found oil/gas in the North Sea.

UK squandered wealth, appeased corporations.

Norway levied 78% tax, took direct stake in companies.

Norway now has $1.8 trillion sovereign fund. UK has public finance crisis.

UK Govts still appeasing corporations/rich.
How sparsely populated Norway amassed $1.8 trillion | Fortune Europe
Launched in the early 1990s to invest mostly in bonds, the fund has grown to become the largest of its kind by acquiring small equity stakes in thousands of companies across the world.
fortune.com
November 18, 2025 at 9:38 AM
Ben's cold-pool paper is online! We switch of cold-pools in Sahel & we "find no statistically significant difference between the diurnal cycles of MCS counts, with continued nocturnal propagation of storms in the experiment" rmets.onlinelibrary.wiley.com/doi/10.1002/...
How sensitive are Sahelian mesoscale convective systems to cold‐pool suppression?
Cold pools are a ubiquitous feature of mesoscale convective systems (MCSs) with important upscale impacts on West African climate, but their role in the maintenance of tropical MCSs remains debated. ...
rmets.onlinelibrary.wiley.com
November 17, 2025 at 9:05 AM
And this is begorw longer-term threat from sea level rise. www.theguardian.com/commentisfre...
November 16, 2025 at 7:45 PM
""The Monnow broke its banks - that is unprecedented in Monmouth." But no mention of why from BBC news

www.bbc.co.uk/news/article...
Monmouth floods prompt 'danger to life' warnings and rescues
Bethan Turner described how she, her father and her boyfriend were left standing on the roof of their submerged car.
www.bbc.co.uk
November 15, 2025 at 9:39 PM
Reposted by John Marsham
“If we wait to cross tipping points before we act, it will be too late. The only credible risk management strategy is to act in advance.”
global-tipping-points.org/the-dartingt...
The Dartington Declaration - Global Tipping Points
The Dartington Declaration has emanated from scientific meetings held at Dartington Hall in England, and then a statement agreed at the Global Tipping Points Conference, on 30 June – 3 July 2025. It w...
global-tipping-points.org
November 15, 2025 at 3:21 PM
#ClimateOfTruth

Never forget that senior UK politicians, whose party's have huge fossil-fuel funding, are spreading mis-leading and/or incorrect information.
www.thenational.scot/news/2369170...

www.carbonbrief.org/factcheck-wh...
November 13, 2025 at 1:36 PM
November 11, 2025 at 12:27 PM
USA & Europe have handed China the chance "to be seen to lead" on a plate
www.theguardian.com/environment/...
Rich countries have lost enthusiasm for tackling climate crisis, says Cop30 chief
Brazil’s André Corrêa do Lago says countries should follow China’s lead on clean energy as conference begins
www.theguardian.com
November 11, 2025 at 8:27 AM
BBC don't need "more" in this sentence.

"there is no clear evidence of an increase or decrease in either their number or intensity. Scientists are more confident that the coastal impacts of windstorms, from storm surges and high waves, will worsen as sea-levels rise."
www.bbc.co.uk/weather/arti...
What difference has ten years of Met Office storm names made to the UK?
Storms were first given names by the UK Met Office ten years ago to raise awareness of the dangers. Elizabeth Rizzini considers if it has worked.
www.bbc.co.uk
November 10, 2025 at 9:36 PM
Reposted by John Marsham
SUPERB and angrily unvarnished response, by former BBC chairman, Lord Patten.

"I don't think that we should allow ourselves to be bullied into thinking that the BBC is only any good, if it reflects the prejudice of the last person who shouted at it." ~AA
November 10, 2025 at 6:40 PM
Great to see @chrisgpackham.bsky.social on Laura Kuenssberg, adverting the National Emergency Climate briefing & calling out fossil-fuel funding of Reform/Tories. Why though does Laura question this as a "suggestion"?
I’ve just announced I’ll be leading a National Emergency Briefing on 27 November . At a time when climate is in free fall on the political agenda , it’s vital our leaders realise what is at stake if we do not accelerate a just , green transition for all .

@nebriefing.bsky.social 🇬🇧
November 9, 2025 at 10:19 PM
Reposted by John Marsham
I’ve just announced I’ll be leading a National Emergency Briefing on 27 November . At a time when climate is in free fall on the political agenda , it’s vital our leaders realise what is at stake if we do not accelerate a just , green transition for all .

@nebriefing.bsky.social 🇬🇧
November 9, 2025 at 12:46 PM
Meanwhile TalkTV & GBNews get away with what they like
November 9, 2025 at 8:03 PM
Reposted by John Marsham
Every MP now has a personal video invitation to the National Emergency Briefing on the #climate & #nature crisis.

This is about ensuring all policymakers are briefed on UK threats and solutions.

Please download and send your MP their invite.
#NEB #TimeToStepUp

docs.google.com/document/d/1...
November 3, 2025 at 9:35 PM
Quick work by @wwattribution.bsky.social

But we don't need this important quantitative attribution for news at the time to explain the role of the climate crisis in storms like Melissa, and the implications for the future. Which often the media fails to do.

www.theguardian.com/world/2025/n...
November 6, 2025 at 1:34 PM
114 dead, mainly due to floods, but no mention of climate change that increases extreme rainfall and storm surge. Or implications for future as sea-level rises, e.g. www.lse.ac.uk/granthaminst...
www.bbc.co.uk/news/article...
Typhoon Kalmaegi: Philippines declares state of calamity after at least 114 dead killed
Kalmaegi left the Philippines on Thursday morning and is currently moving toward central Vietnam.
www.bbc.co.uk
November 6, 2025 at 8:40 AM