Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 23/07/2026Why do cities exist at all? Luis Bettencourt sees that as a fundamental unresolved question in urban science, and one from which all others may follow. 131
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 20/07/2026"We don’t know if this is a good idea. We don’t know if this is necessary. We don’t know what the costs are of trying to impose such a limit." Lewis Dijkstra notes that many major policies treat urban sprawl as inherently bad. 121
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 21/07/2026"We know more about rivers in the Arctic than we do about urban rivers" That's the unresolved problem posed by Josh Dean in this lightning talk. Cities are shaped and used by people daily, yet we understand their ecological systems far less than remote wilderness. 121
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 09/07/2026And now for a fiendish (unresolved) question from @martinfleischmann.net: "What is a building?" Sometimes questions with apparently obvious answers are very confusing on closer inspection! 021
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 09/07/2026In this lightning talk, Somwrita Sarkar asks one of the most important (and unresolved) questions in urban science: "When do 'good' inequalities turn into 'bad' inequalities?" See Somwrita's full lightning talk at youtu.be/GFOOTqpbMEw pluslab.bristol.ac.uk/launch-sympo... #urbanscience #inequality 011
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 08/07/2026Find out more about the +Lab launch symposium in our short overview video. Short talks from the event being added daily here: pluslab.bristol.ac.uk/launch-sympo... @bristoluni.bsky.social 021
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 13/07/2026"Who is likely to live where?" In this lightning talk, Felix Agyemang proposes that – despite decades of progress in urban land-use modelling – predicting where development happens, and who ends up living there, remains a key unresolved problem in urban science. 121
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 13/07/2026Steam 🚂 Jet engines ✈️ Air conditioning ❄️ Teleconferencing 🖥️ Now AI. Emmanouil Tranos unpacks the feedback loop between new technologies and cities — tech is born in cities, then reshapes what cities are and do. 111
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 13/07/2026So where does AI take us? Driverless cars? Wealth redistribution? Cities will have to react - but slowly given the sunk cost locked into buildings and infrastructure. See Emmanouil's full lightning talk at youtu.be/0GGdmlviLno?... pluslab.bristol.ac.uk/launch-sympo... #UrbanScience #Cities 011
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 09/07/2026“You will be more influential than Jane Jacobs. More than Patrick Geddes. Not because you're smarter — because more people are living urban lives today than ever before, and the ideas we act on now will shape more of them than any generation's have.” 111
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 10/07/2026More data won't save urban planning. In this lightning talk, @geoffboeing.com argues that the field's toughest problems — congestion, air pollution, and beyond — aren't just technical puzzles waiting for one more coefficient. 121
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 08/07/2026What is urban? Director @seanurban.bsky.social's opening talk from our symposium on "unsolved problems in urban science". More short talks from the event being added daily here: pluslab.bristol.ac.uk/launch-sympo... 021
Reposted by Sean Fox+Lab @ University of Bristol @pluslab.bsky.social · 07/07/2026📽️ 🎬 🎞️ The first videos from the +Lab launch symposium on "Unsolved problems in urban science" are now available! First, a short overview explaining why we organised the symposium and what we want it to achieve. pluslab.bristol.ac.uk/launch-sympo... ⚡Individual lightning talks to follow soon... 122
Reposted by Sean FoxArndt Leininger @aleininger.bsky.social · 30/04/2026📢 We're hiring for my project RESPOL on residential mobility & electoral realignment 📍 University of Hamburg 📅 4y, 75% FTE 🔍 pol behavior, comp politics, regional inequalities 📊 quant, administrative & survey data Please share with talented MA students! 🔗 www.uni-hamburg.de/en/stellenan...uni-hamburg.deJob advertisement 04946
Reposted by Sean FoxAndrew Carter @andrewcities.bsky.social · 18/04/2026What is a city without children? giftarticle.ft.com/giftarticle/...giftarticle.ft.comWhat is a city without children?As urban housebuilding strategies around the world increasingly push families out, the ‘sidewalk ballet’ — and heart — of community life is under threat 021
Reposted by Sean FoxCameron Blevins @cblevins.bsky.social · 03/04/2026This is so, so well-articulated. 97107603880
Reposted by Sean FoxDavid Zipper @davidzipper.bsky.social · 26/03/2026Manhattan's congestion pricing program has been a stunning success. Other US cities have noticed. Could Chicago go next? In @bloomberg.com, I explored. 🧵bloomberg.comCould Congestion Pricing Pay Off for Chicago?Second City leaders have discussed following Manhattan’s lead in tolling roads to ease traffic. But a Chicago-style version of New York’s policy might look very different. 513329
Reposted by Sean FoxPeter Walker @peterwalker99.bsky.social · 25/03/2026NEW: Councils in England are for the first time to receive guidance on how to create streets that are safer for women and girls, as ministers try to tackle what they describe as systemic unfairness in people’s ability to walk around their own neighbourhood. www.theguardian.com/politics/202...theguardian.comEnglish councils to get guidance on designing safer streets for women and girlsLocal transport minister describes initiative as fundamental issue of fairness in people’s ability to walk in their neighbourhoods 24313
Reposted by Sean FoxGeoff Boeing @geoffboeing.com · 24/03/2026Marc Barthelemy and I recently published an article in Physical Review Letters titled "Universal Model of Urban Street Networks." We present an algorithm to generate urban street networks that reproduce key empirical characteristics. Paper link: doi.org/10.1103/1vj4... Here's a short summary... 1186
Sean Fox @seanurban.bsky.social · 24/03/2026🚨 We’re Hiring! 🚨 We're recruiting a Lecturer in Sustainable Urban Development. 3-year post in the School of Geographical Sciences @bristoluni.bsky.social #cities #sustainability #sustainabledevelopment 👉 Here’s the job advert: www.bristol.ac.uk/jobs/find/de...bristol.ac.ukDetails | Working at Bristol | University of Bristol 031
Reposted by Sean FoxCarl Müller-Crepon @carlmc.bsky.social · 20/03/2026I'm very excited that you all can now read about Itinerant Rule in the Holy Roman Empire from 919-1519 in the @ajpseditor.bsky.social! Thank you @claranw.bsky.social, @andrejkokkonen.bsky.social and Jørgen Møller for a great collaboration! onlinelibrary.wiley.com/doi/10.1111/... 86722
Reposted by Sean FoxProf Lisa Schipper 🌍🍉💪 @lisaschipper.bsky.social · 20/03/2026Have you heard of paper mills? If you are an academic and especially if you are a journal editor, you will know what this is. Even so, this video was really eye-opening. www.youtube.com/watch?v=SEwi...youtube.comI tried to buy a scientific paperYouTube video by Christophe 0158
Reposted by Sean FoxSharon O'Dea @sharonodea.com · 26/02/2026Quite rare to see a chart that says quite so overtly that no one involved has the slightest clue what’s happening here 2143445595
Sean Fox @seanurban.bsky.social · 25/02/2026Get a bike! www.scientificamerican.com/article/a-hu...scientificamerican.comThe Most Efficient Traveler Isn’t a Bird or a Fish—It’s You on a BikeA famous graphic, now updated, compares locomotion in the animal kingdom 010
Sean Fox @seanurban.bsky.social · 25/02/2026Net zero will transform Britain’s economy – our map reveals the most vulnerable places theconversation.com/net-zero-wil...theconversation.comNet zero will transform Britain’s economy – our map reveals the most vulnerable placesThe most vulnerable places are, overwhelmingly, the same places that suffered industrial decline in the 1980s. 021
Reposted by Sean FoxDavid Zipper @davidzipper.bsky.social · 22/01/2026A surefire way to make transportation more abundant and affordable? Increase density. In Bloomberg, I explained why. 🧵bloomberg.comAchieving ‘Transportation Abundance’ Is All About DensityTo drive down transportation costs and move the needle on affordability, Americans need to embrace living closer together. 310525
Reposted by Sean FoxThe Quarterly Journal of Economics @qjeharvard.bsky.social · 16/10/2025Recently accepted by #QJE, “The Price of Housing in the United States, 1890–2006,” by Lyons (@ronanlyons), Shertzer (@econhist-allday), Gray (@econhistoryorbust), and Agorastos: doi.org/10.1093/qje/...doi.orgThe Price of Housing in the United States, 1890–2006*Abstract. We construct the first annual market rent and home sales price series for American cities over the 20th century using 2.7 million newspaper real 04816
Reposted by Sean FoxMichael Li (李之樸) @mcpli.bsky.social · 31/12/2025The final Calvin and Hobbes, which appeared in papers 30 years ago today. 122130484237
Reposted by Sean FoxGabriel Zucman @gabrielzucman.bsky.social · 12/12/2025It has become received wisdom in Brussels and Washington that there is a new “euro-sclerosis”: that the EU economy is lagging the US This view is wrong A little primer on the measurement of productivity – and why reports of the economic death of Europe are greatly exaggerated🧵 251167602
Reposted by Sean FoxBrent Toderian @brenttoderian.bsky.social · 11/12/2025“Air pollution fell substantially as Paris restricted car traffic and made way for parks, people-streets and bike-lanes.” Better for the climate, better for health, better for livability and quality of life. Common sense. Such a no-brainer, it’s remarkable that more cities HAVEN’T done the same.washingtonpost.comParis said au revoir to cars. Air pollution maps reveal a dramatic change.Air pollution fell substantially as the city restricted car traffic and made way for parks and bike lanes. 9738266
Reposted by Sean FoxBrent Toderian @brenttoderian.bsky.social · 09/12/2025Never forget, car dependency isn’t freedom. Some might ask “what’s more free than cars?” Choices. Choices are more free than car dependency. It’s not a hard concept. I’m not pitting cars against any other single mode of transport. I’m rejecting design that creates dependency on just one mode. 16678180
Reposted by Sean FoxJarrett Walker @humantransit.bsky.social · 02/12/2025Is your transit agency "succeeding"? It depends on the definition of success, and not everyone agrees on that. Here's my timeless article on this, just now updated a bit. humantransit.org/2018/02/basi...humantransit.orgBasics: The Ridership - Coverage Tradeoff — Human TransitIs your transit agency succeeding? It depends on what it’s trying to do, and most transit agencies haven’t been given clear direction about what they should be trying to do. Different people have di... 0389
Sean Fox @seanurban.bsky.social · 17/11/2025Interesting chart on the fall and rise of Asia in the global economy (and the rise and fall of the "West") courtesy of @data.ft.com 041
Reposted by Sean FoxScott Lincicome @scottlincicome.bsky.social · 10/11/2025New @nberpubs: "The Economic Impact of Brexit" www.nber.org/papers/w34459 "by 2025, Brexit had reduced UK GDP by 6% to 8%, with the impact accumulating gradually over time." 😲 12518
Sean Fox @seanurban.bsky.social · 08/11/2025This is very cool research on how the built environment may affect political behaviour 020
Reposted by Sean FoxCarla Denyer @carladenyer.bsky.social · 09/10/2025Govt promised to help Palestinians get to UK to study- but I'm in touch with 7 young Palestinians with scholarships at @bristoluni.bsky.social who are trapped in Gaza because the Home Office isn't doing what was promised Shocking neglect putting lives at risk www.aljazeera.com/opinions/202...aljazeera.comAccepted but trapped: Why won’t the UK evacuate its students from Gaza?Palestinian students in Gaza who earned places at top UK universities are being stranded by political indifference. 110955
Reposted by Sean FoxDr Jessica Hagen-Zanker @j-hagen-zanker.bsky.social · 26/09/2025It’s party conference season – and bombastic statements on immigration are at the top of playlists. I for one am tired of hearing the same old emotionally charged promises that just don’t relate to reality. You too? Here are five things you should be hearing about immigration, but won’t be. 062
Sean Fox @seanurban.bsky.social · 19/09/2025🌍📢 Call for Papers!! Urban Studies seeks submissions for a special issue on Climate Urbanism, Resilience & Justice — exploring how cities confront the climate crisis, risk, & inequality. @urbanstudiesjournal.com @acuto.bsky.social www.urbanstudiesjournal.com/callforpaper...urbanstudiesjournal.comClimate Urbanism, Resilience, and Justice - Urban StudiesUrban Studies Journal Call for Papers is now open: Climate Urbanism, Resilience and Justice. Submission deadline: 31 January 2026. 099
Reposted by Sean FoxClaus Pörtner @clausportner.bsky.social · 19/08/2025New in Demography: ‘How Is Fertility Behavior in Africa Different?’ Using DHS/MICS data, SSA–other-region fertility gaps rise through primary school and narrow at higher schooling; little difference among women with secondary+. doi.org/10.1215/0070... @readdemography.bsky.social @seattleu.edudoi.orgHow Is Fertility Behavior in Africa Different? | Demography | Duke University Press 184
Sean Fox @seanurban.bsky.social · 27/08/2025Really enjoyed taking part in this conversation with Divya Gupta & Gregory Randolph on #urbanization and #inequality in India on the In Common Podcast: www.incommonpodcast.org/podcast/136-...incommonpodcast.org136: Urbanization and Inequality with Sean Fox and Gregory RandolphIn this episode, Divya speaks with Sean Fox and Gregory Randolph about urbanization and how it is unfolding amid global shocks and affecting inequality. Sean Fox is a Professor of Geography and Globa 041
Reposted by Sean FoxAndrew Carter @andrewcities.bsky.social · 27/05/2025Deadline is June 1st (23.59). 012
Reposted by Sean FoxRebecca Sear @rebeccasear.bsky.social · 22/05/2025"oral contraceptives may be lowering all-cause mortality in women: either through the modification of mortality risk at all ages or, possibly, by modifying aging rates and mortality rate doubling times through the synthetic modification of adaptive pathways" www.nature.com/articles/s44...nature.comReproductive milestones and oral contraceptive timing predict late-life mortality - npj Women's Healthnpj Women's Health - Reproductive milestones and oral contraceptive timing predict late-life mortality 084
Reposted by Sean FoxBrent Toderian @brenttoderian.bsky.social · 29/04/2025This is interesting — a recent study of mode share (the % share of transportation trips by car, transit, walking, biking etc) relative to city size and income levels in almost 800 cities in 61 countries. Interesting results. HT @davidzipper.bsky.social www.sciencedirect.com/science/arti... 31631244
Reposted by Sean FoxCentre for Cities @centreforcities.bsky.social · 29/04/2025BRIEFING | The myth of “left behind” ❓How should government respond to the political discontent signalled by the vote to leave the European Union and the more recent rise of Reform UK? buff.ly/g8K7EDQ 👇 1398
Reposted by Sean FoxNuno Palma @nunopgpalma.bsky.social · 07/04/2025𝗦𝘁𝗮𝘁𝗲 𝗰𝗮𝗽𝗮𝗰𝗶𝘁𝘆 𝗮𝗻𝗱 𝗲𝘅𝗲𝗰𝘂𝘁𝗶𝘃𝗲 𝗰𝗼𝗻𝘀𝘁𝗿𝗮𝗶𝗻𝘁𝘀 𝗶𝗻 𝗲𝗮𝗿𝗹𝘆 𝗺𝗼𝗱𝗲𝗿𝗻 𝗘𝘂𝗿𝗼𝗽𝗲 New paper by K. Karaman, A. Henriques, & myself. Contrary to conventional wisdom we find that constrained government & state capacity were not systematically related. England stood out for combining both which helps explain its take-off 1101
Reposted by Sean FoxCatrin Einhorn @catrineinhorn.bsky.social · 27/03/2025From state legislatures to community groups, from tribal lands to city parks to postage-stamp backyards, people are doing quiet, vital work to confront climate change and biodiversity loss. All year, @carabuckley.bsky.social and I will be writing about these efforts. www.nytimes.com/interactive/...nytimes.com50 States, 50 FixesA series about local solutions, and the people behind them, to environmental problems. 35819
Reposted by Sean FoxESRC Centre for Population Change and Connecting Generations @cpc-cg.bsky.social · 27/03/2025Andy Tatem & Jessica Espey @worldpop-uos.bsky.social report on the growing global crisis in #population data in @theconversation.com. Please share across your networks 📨 "When people vanish from data, they vanish from policy... causing political underrepresentation & inadequate resource allocation"theconversation.comGlobal population data is in crisis – here’s why that mattersWhen certain groups of people are systematically undercounted, they become invisible to policymakers. 085
Reposted by Sean FoxNBER @nber.org · 27/03/2025Sewer access shapes developing world cities. New research shows effects on population density as large as for highways, but little on demographics, from Sean E. McCulloch, Matthew P. Schaelling, Matthew Turner, and Toru Kitagawa www.nber.org/papers/w33597 0133
Reposted by Sean FoxRebecca Sear @rebeccasear.bsky.social · 25/03/2025Nice article on population projections, making the point that one problem with population panics is that it’s incredibly difficult to predict population trends. Implementing drastic policy solutions on the basis of long-term population projections is therefore not a good ideavox.comThe mysterious statisticians shaping how we think about fertilityExperts were wrong about overpopulation before. Could they be wrong about underpopulation now? 63613
Reposted by Sean FoxBrent Toderian @brenttoderian.bsky.social · 23/03/2025My semi-regular reminder of a really important reality about cities, density, services and taxes. Any questions? Graphic recently cleaned up by @kathrynmathias.bsky.social. #CityMakingMath 18665211