and would it be true to say that regenerative braking on electric cars reduces significantly this dust?

It&#x27;s true that brake dust is the primary PM2.5 emission from vehicles in an urban environment. However the PM2.5 component from tail pipes are still very significant, higher than the contribution from tires.The order is:1. brake dust
2. road dust
3. engine emissions
4. tire dust<a href="https:&#x2F;&#x2F;www.sciencedirect.com&#x2F;science&#x2F;article&#x2F;abs&#x2F;pii&#x2F;S0045653519305831" rel="nofollow">https:&#x2F;&#x2F;www.sciencedirect.com&#x2F;science&#x2F;article&#x2F;abs&#x2F;pii&#x2F;S00456...</a><a href="https:&#x2F;&#x2F;electrek.co&#x2F;2025&#x2F;05&#x2F;27&#x2F;another-way-electric-cars-clean-the-air-study-says-brake-dust-reduced-by-83&#x2F;" rel="nofollow">https:&#x2F;&#x2F;electrek.co&#x2F;2025&#x2F;05&#x2F;27&#x2F;another-way-electric-cars-cle...</a>

Diesel looks good if you are focusing primarily on fuel economy (mpg &#x2F; L&#x2F;100km), and when companies cheat the tests on other emissions:<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Volkswagen_emissions_scandal" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Volkswagen_emissions_scandal</a>When you remove the cheating and give adequate weight to those emissions, diesel for passenger vehicles makes a lot less sense.

Modern diesel engines with DPF and DEF are pretty clean from a particulate and NOx standpoint. Of course there are still older diesels on the road, mainly buses and trucks. In the USA, diesel is so unpopular as a passenger car engine that it&#x27;s not even worth worrying about.

&gt; The love for diesel engines in many European countries was always confusing to me.That&#x27;s a thing of the past as as early as in 2023 diesels were already a smaller percentage of new cars than non-hybrid EVs:<a href="https:&#x2F;&#x2F;www.acea.auto&#x2F;figure&#x2F;fuel-types-of-new-passenger-cars-in-eu&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.acea.auto&#x2F;figure&#x2F;fuel-types-of-new-passenger-car...</a>To add to what others said: diesels always had a reputation of reliability. The cast-iron TDI 1.9 is legendary but even Italian cars fitted with the JTD line would just work and not require maintenance. I recall making light of a friend who was driving an Alfa Romeo until he mentioned that actually it&#x27;s been more reliable than anything else he&#x27;s driven - at least in terms of powertrain issues.

&gt;The love for diesel engines in many European countries was always confusing to me.It&#x27;s expressly incentivized by their tax system.Imagine the year is 1988 and you&#x27;re some snooty jerk in Europe about to buy a Mercedes. Why on earth would you go with the noisy, smelly diesel option if not to save A TON of money over the life of the vehicle?

The love for diesel came from a catastrophic misunderstanding and the resulting belief that CO2 must be reduced at all costs. Diesel engines of the past produced slightly less CO2 per km than petrol engines in exchange for much worse overall emissions. The fact that they were slightly more efficient in terms of fuel consumption helped with the sales pitch, too.

&gt; The love for diesel engines in many European countries was always confusing to me.And turns out the whole thing was a lie. <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Diesel_emissions_scandal" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Diesel_emissions_scandal</a>It&#x27;s unfortunate that so much rhetoric around environmentalism is based on faulty claims. It&#x27;s starting to make me sceptical of environmental claims in general.The latest one is AI data center water use- the extreme numbers like 5 liters of water per ChatGPT image just makes me feel sad that we can&#x27;t have a civil discussion based on the facts. Everything is so polarized.

When I was at the military they told us that in case of war the government would start appropriating diesel cars, since those are compatible with the fuel the military uses and that there were ancient incentives to buy this type of car to make sure there were enough of them.

Diesel was promoted in the UK when we were worried about CO2 emissions. There was a subsequent back-pedal when particulates became a prominent issue

I believe the popularity of diesel car in Europe is actually a tax-related hack.The idea is that diesel is the &quot;work&quot; fuel, for shipping, construction, etc... While gasoline is the &quot;consumer&quot; fuel, for personal use, motorsports, etc... Make the former expensive and it will affect the entire economy, everything will become more expensive and less competitive. Making gasoline more expensive will not have the same impact.So, put high taxes on gasoline. The result was an increase in popularity of diesel cars, that cost less to run because of taxes.Now, the situation is changing. Diesel, at least the one that is legal to use on the road is taxed at a level closer to gasoline. Diesel cars are also becoming less and less welcome with regards to low emission zones and green taxes, so many people are going back to gasoline.

&gt; though diesel engines spit out a bunch of bad stuff.Exactly. The noxious tailpipe emissions in a city are usually from diesel trucks, small vehicles like motorcycles (small or absent catalytic converters), modified vehicles (catalytic converter removed or diesel reprogrammed to smoke), but not modern gasoline ICE vehicles.The love for diesel engines in many European countries was always confusing to me.PM2.5 is also a broad category of particulates that come from many sources. The PM2.5 levels in the air depend on many sources, with wind being a major factor in changing PM2.5 levels. It’s hard to draw conclusions when a number depends on the weather and a lot of other inputs.

That source is Europe, not New York. It claims EV&#x27;s are 24% heavier than ICE vehicles. That might be true in Europe but definitely not the case in the US where the average ICE vehicle is a 6000 pound truck and the average EV is a 4000 pound Tesla.It also assumes they&#x27;re using the same tires. EV owners put on EV tires, which are formulated to have a lower rolling resistance, quieter and last longer. All 3 of those correlate with lower dust.

&quot;relatively clean&quot; means 85% of PM2.5 is from non-exhaust sources, and 15% is from exhaust after catalytic conversion. In New York EV and ICE are pretty much on par when it comes to this category of pollution, as the additional weight increases non exhaust sources. 
Source: <a href="https:&#x2F;&#x2F;www.sciencedirect.com&#x2F;science&#x2F;article&#x2F;abs&#x2F;pii&#x2F;S135223101630187X" rel="nofollow">https:&#x2F;&#x2F;www.sciencedirect.com&#x2F;science&#x2F;article&#x2F;abs&#x2F;pii&#x2F;S13522...</a>It is different in Africa, where catalytic converters are harvested for precious metals and cars are driven without them.

Afraid the intuition is somewhat incorrect.Similar to with tire wear what&#x27;s important to emissions is the amount of force that has to be applied to decelerate and how often it occurs. At highway speeds it&#x27;s far less of an issue, but in slow speed urban environments with lots of stop start driving and high vehicle densities it&#x27;s a real problem.See for instance <a href="https:&#x2F;&#x2F;uk-air.defra.gov.uk&#x2F;assets&#x2F;documents&#x2F;reports&#x2F;cat09&#x2F;1907101151_20190709_Non_Exhaust_Emissions_typeset_Final.pdf" rel="nofollow">https:&#x2F;&#x2F;uk-air.defra.gov.uk&#x2F;assets&#x2F;documents&#x2F;reports&#x2F;cat09&#x2F;1...</a>

Tires and brakes. With EV&#x27;s this gets relatively worse because they are heavier.

Folks in the comments will say &quot;not really&quot; for EVs because of better control and lower speeds, but if you&#x27;ve ever driven in Manhattan, you&#x27;d know it&#x27;s often light-to-light drag racing at times which with an EV and a heavy foot will undo a lot of the regen braking via stress on the tires.

Is that true for slower moving vehicles? I can&#x27;t imagine there&#x27;s a lot of brake dust generated by stopping &amp; starting in the 0-10 mph range.

Why does everyone immediately pivot to EVs on this subject, instead of (looks around) gargantuan SUVs and trucks everywhere, due to peculiarities of US policies regulating SUVs more leniently than cars on fuel efficiency?

EV&#x27;s produce 38% less tire &amp; brake dust than ICE vehicles.<a href="https:&#x2F;&#x2F;electrek.co&#x2F;2025&#x2F;05&#x2F;27&#x2F;another-way-electric-cars-clean-the-air-study-says-brake-dust-reduced-by-83&#x2F;" rel="nofollow">https:&#x2F;&#x2F;electrek.co&#x2F;2025&#x2F;05&#x2F;27&#x2F;another-way-electric-cars-cle...</a>non-exhaust emissions on an ICE vehicle are roughly 1&#x2F;3 brake dust, 1&#x2F;3 tire dust and 1&#x2F;3 road dust. EV&#x27;s have almost no impact on road dust, 83% lest brake dust and 20% more tire dust.

Tire wear on EVs has more to do with the weight of your right foot than the curb weight of the vehicle.The high torque of EVs results in frequent wheel slippage for those eager to pull away from traffic lights quickly. Just like with high BHP ICE vehincles, smooth and gentle acceleration&#x2F;deceleration will result in long tire life.

I&#x27;m not sure, and I assume it will vary a lot by speed.EVs do also have higher torque, so that may increase tire-based particles, but you&#x27;re right that it avoids the brake pads for the most part.Fewer cars in general is the win from congestion pricing, though.

With EV&#x27;s this gets relatively worse because they are heavier. EV SUV worse than gas SUV.

I&#x27;d gonna guess &quot;worse&quot;Brake dust is mostly some iron, carbon, silica. Not great to ingest but very much recyclable by the environment, unlike rubber.And possibly much easier to greatly reduce (just build some shielding around the brake to catch most of the dust) than the tyre

A bit worse on tires because they are heavier (for comparable vehicle size, but obviously not if you compare a small EV with a ICE truck), and much better on brakes because of regenerative braking. Overall they are better.

And unfortunately there is some nasty stuff in tires

“Additional weight”? What additional weight? In comparison to America’s best-selling vehicle, the Ford F-150? Where was all this hand-wringing about weight and brake and tire dust ten years ago?I guess those narratives aren’t going to support themselves.

How do EVs fare in this regard? Brakes are used significantly less, but the additional weight from the batteries chews through tires faster.

My assumption is that stop signs act somewhat as a way to enforce the lower speed limits in residential areas. There&#x27;s several stretches without stops in my suburb where I&#x27;ve seen drivers whizzing by very obviously above the 25mph speed limit, which is bad enough on its own but becomes a serious hazard when combined with the massive blind spots that come from curbs on both directions being filled to the brim with parked cars.A better solution would probably be radar-based speed signs with printed threats of fines, though.

They added a stop sign near me, and now I get to hear the engines rev as they accelerate.The EVs passing by are nice, though!There were a number of accidents which prompted the 4 way stop.

It always surprises me when people want stop signs in their neighborhood for traffic calming. The last thing I want is all of the noise and pollution of vehicles stopping and starting over and over again; surely various piece of road furniture like bulb-outs, roundabouts, etc, do a better job with fewer drawbacks. Other than cost, of course.

There are some early tyre and brake dust collection systems which might help, but that won&#x27;t do much for the road dust.I&#x27;ve been wondering whether, theoretically, if self driving cars become widely usable and deployed in cities, will they be able to safely operate with harder tyre compounds and harder road surfaces that shed less but don&#x27;t grip as well?If nothing else, less aggressive driving should lead to less shedding.

There’s also ammonia from farmland, it reacts to form secondary PM25

I wonder if it is the `congestion` itself that causes the PM2.5 spike. More stop and go traffic, more brake dust, more tire dust?

Congestion leads to more use of the brakes, which can have nonlinear effects.Also, I thought tire particles tend to be larger.

co2, co, NO.Nothing i would breath in a garage. Nothing i like to breath in while i&#x27;m driving.

I am a little confused, why would sloppiness in the media release (the article that uses the word tailpipe), have anything to do with sloppiness in the study, which the above comment clearly highlights is about PM2.5, not specifically tailpipe emissions?Are Yale&#x27;s media releases typically done by the people who do the study?

The study isn’t sloppy, and I would highly suggest reading it before casting aspersions at the authors:<a href="https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s44407-025-00037-2" rel="nofollow">https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s44407-025-00037-2</a>

The study doesn&#x27;t mention tailpipes (afiact). This press release&#x2F;article does. Don&#x27;t dismiss scientists because journalists reporting their findings incorrectly.

This is actually a major nitpick. If this &quot;study&quot; is this sloppy, what else isn&#x27;t quite true?

I won&#x27;t change my mind about emissions in NYC. NYC is full of modern, western cars.Two-stroke engines are terrible, classic automobiles are terrible, cars with no emission regulations will tend to be terrible. Cars in NYC will have catalytic converters and other technologies to reduce tailpipe emissions.

They have different ICE engines. Many two stroke scooters. Emissions are way different from those tailpipes. You’re doing apples to oranges comparisons.

<pre><code> Minor nitpick, but tailpipes aren&#x27;t the primary source of emissions. 
</code></pre>
Spend some time in Hanoi or Ho Chi Minh City or a very dense city in Asia and then come back here. Let me know if you change your mind.

Calculating Air Pollution’s Death Toll, Across State Lines - <a href="https:&#x2F;&#x2F;www.nytimes.com&#x2F;2020&#x2F;02&#x2F;12&#x2F;climate&#x2F;air-pollution-health.html" rel="nofollow">https:&#x2F;&#x2F;www.nytimes.com&#x2F;2020&#x2F;02&#x2F;12&#x2F;climate&#x2F;air-pollution-hea...</a> | <a href="https:&#x2F;&#x2F;archive.today&#x2F;HEapE" rel="nofollow">https:&#x2F;&#x2F;archive.today&#x2F;HEapE</a> - February 12th, 2020Premature mortality related to United States cross-state air pollution - <a href="https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s41586-020-1983-8" rel="nofollow">https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s41586-020-1983-8</a> | <a href="https:&#x2F;&#x2F;doi.org&#x2F;10.1038&#x2F;s41586-020-1983-8" rel="nofollow">https:&#x2F;&#x2F;doi.org&#x2F;10.1038&#x2F;s41586-020-1983-8</a>

&gt; I thought that smoking and bad dietary&#x2F;exercise habits were the main factorsWhile that is true, PM2.5 is still a major cause of lung cancer in non smokers, see e.g.<a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC11729863&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC11729863&#x2F;</a><a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC11969995&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC11969995&#x2F;</a>

Air pollution is pretty clearly correlated with reduced life expectancy, even if you don&#x27;t directly die from it

I can choose to eat healthy and not smoke. I can&#x27;t choose not to breathe.

And besides, even if lung cancer and heart attack may be the most common means of premature death, it does not entail that air pollution is the primary cause of them. I thought that smoking and bad dietary&#x2F;exercise habits were the main factors. Please correct me if I&#x27;m wrong, I&#x27;d like to know.

&gt; Particulates issued from tailpipes can aggravate asthma and heart disease and increase the risk of lung cancer and heart attack. Globally, they are a leading risk factor for premature death.Minor nitpick, but tailpipes aren&#x27;t the primary source of emissions. The study is about PM2.5[0]. which will chiefly be tires and brake pads. Modern gasoline engines are relatively clean, outside of CO2, though diesel engines spit out a bunch of bad stuff.[0] <a href="https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s44407-025-00037-2" rel="nofollow">https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s44407-025-00037-2</a>

&gt; Best they can do now is, “Well, we’re not New York&quot;But that&#x27;s a real argument. They&#x27;re not a $1.3tn economy ($1tn of which is Manhattan alone) [1] with fewer than one car per household (0.26 in Manhattan) [2].[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Economy_of_New_York_City" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Economy_of_New_York_City</a>[2] <a href="https:&#x2F;&#x2F;www.hunterurban.org&#x2F;wp-content&#x2F;uploads&#x2F;2024&#x2F;06&#x2F;Car-Light-NYC-Infographics-May-2024.pdf" rel="nofollow">https:&#x2F;&#x2F;www.hunterurban.org&#x2F;wp-content&#x2F;uploads&#x2F;2024&#x2F;06&#x2F;Car-L...</a>

It’s a national issue because as soon as one city tries it out and it turns out to be pretty good and none of the doom scenarios ensue, congestion-charge opponents all over America lose most of their talking points.Best they can do now is, “Well, we’re not New York.”

Attention economy, the algorithm, rage-bait, maximizing engagement, doomscrolling - pick your buzzword. Individual people care about all sorts of weird things, but on average, this and no other reason is why a person in Idaho suddenly finds themselves caring about Manhattan congestion pricing. It&#x27;s easy to point a finger and laugh&#x2F;marvel when it&#x27;s something so obviously absurd to you, but of course you and I both have entirely different blind spots where our attention is marshalled and our opinion is formed by the rage-bait engine. Ours must seem preposterous to those on the outside looking in, too.

...did you respond to the wrong comment?

Probably very clear-cut, right? &quot;No parking, no business&quot; never made sense, but it makes even less sense in a city where cars are involved in less than a third of all tripsEspecially considering that* Congestion is an opportunity cost in itself already, which is paid in wasted time by all road users, impacting mostly those who spend a long time on the road, which is busses, taxis, professionals and delivery drivers, as they spend the most amount of time actually driving in congested roads* Congestion pricing forces trips to self-select on cost&#x2F;benefits in actual dollars, instead of time, so you optimize for wealthier trip takers, short stays or high value trips, where before you would favor long stays (which make looking for parking forever not so bad), and people who don&#x27;t value their time very much* Car use remains heavily subsidized, as motorists do not come close to paying the full costs associated with their road usage

&gt; The strength of conviction people have about this policy–almost either way, but certainly among those against–seems to scale with distance from the city.Writing this from mid-town Manhattan. There are a lot of strong feelings about congestion pricing. It was a common topic in the local media. The stronger voices tend to be those who drive and are affected by it. For Manhattan that is a relatively low percent of the population.There are some people who are pro-congestion pricing, but as often has with these things the benefits are distributed whereas the costs are concentrated, leading to certain behavior.

You run in very different social circles than I do. The only complaint I have ever heard about California&#x27;s high speed rail plan (as a life-long Bay Area resident) is how damn long it&#x27;s taking because of the yokels claiming it&#x27;ll annoy their cows and almonds.

Just to defend myself (similar to what I said in a different thread): I live in an area that would be marginal for high speed rail, but I still want it. If the US can get a great high speed rail network it would make sense to bring that to me, but as one of the last lines built! If CA can&#x27;t build a good HSR where it should obviously work out there is no way it is worth trying here. They have to make the mistakes and then learn from them (this is the harder part!) in order to bring something to me where there can be no mistakes.

Feels like this is the curse of modern US politics. I&#x27;m convinced the majority of people that &quot;want high speed rail in CA&quot; don&#x27;t live in CA. Further away they live, the stronger they will argue for why we should have it.

It&#x27;s because everything is a culture war issue now, and anything remotely seen as helpful or benefitting society or taking even an inch from cars is &quot;bad&quot; for the people who live in places like Idaho (and Staten Island).

I agree, and would add that there are others who are decidedly &quot;anti-car&quot; and you could say that this is part of their identity. This particular policy may be a strictly positive (no strong opinion here), but when viewed as part of the broader disagreement it drives some of the reflexive pushback.

&gt; Cars are en extension of some Americans&#x27; identityi hear this a lot and i also feel like this population is declining very significantly for a lot of reasons (cars that people care about are unaffordable, most cars on the road tend to fit into one of a very small number of categories, people find other ways to navigate depending on where they live, people don&#x27;t do as many activities out of the home that require a vehicle, etc). at what point does the real population of car enthusiasts become small enough to be irrelevant in public policy and infrastructure decisions?

Cars are en extension of some Americans&#x27; identity and driving is something they feel utterly entitled to.I&#x27;ve lived all over the world and in NYC for decades so it seems silly to me. Bust most Americans have never seen or ridden an effective form of public transport. So they view congestion pricing as an infringement on their rights and quality of life.

Because success would encourage it in other cities facing terrible traffic.People say they hate socialism, but drivers love car-socialism.

You&#x27;re curious how an issue where government listening to experts results in obvious good outcomes and no serious failures became a national culture war issue?

There are reliable ways to transform American rhetoric to collectivist vs. individualist.&quot;We should toll roads&quot;. This will reliably produce &quot;we should all contribute through tax to the maintenance of roads and they should be considered a public good&quot;.&quot;We should have land value taxes&quot;. This will reliably produce &quot;we should not have to pay rent to the government for something that we own&quot;.A simple self-interest model will capture all participants in this discussion. This is why economically optimal policies have such opposition. People don&#x27;t want to pay the price for their actions. They&#x27;re ideally hoping to have someone else pay it. It is just as common for a position like funding for SF&#x27;s Muni.Propositions J and K made it clear. One said &quot;let&#x27;s raise Muni spending&quot;. The other said &quot;if we raise sales tax, that will go to Muni spending. If we don&#x27;t, the Muni spending proposition dies&quot;. People voted for the first and against the second. Pretty straightforward position: &quot;We should spend more money but from a place that is not me&quot;.The way welfare is organized in the US also shows this. Welfare is the largest sector of the US federal budget, and the ideal is to tax all productive capacity to pay for the aged. This aligns with the increased vote share from the aged. The classic two wolves and a sheep at dinner.

New York has long been an influential city. It was the Robert Mosses deputies that spread all over the US to drive highways threw every city center. If New York can do something, it might be copied everywhere.That and right-wing politics where anything that harms the car as a religious symbol is seen as a &#x27;values&#x27; based attack.

&gt; It&#x27;s because Trump made it one of his obsessions for a period of time, putting it on the MAGA radarHad most people outside the tri-state area not heard and formed an opinion about congestion pricig before Trump brought it up?

It&#x27;s because Trump made it one of his obsessions for a period of time, putting it on the MAGA radar.

I think this comment is a great example of what the OP is talking about. Your comment is completely divorced from the context of congestion pricing in New York City. For example:&gt; Taking a basic task like driving into the city, something many people are forced to do for workThat is simply not the case in NYC. Very, very few people must drive into the center of Manhattan to work. It was already unaffordable to do so anyway because parking is incredibly expensive. People take the subway. Car ownership is already disproportionately preserved for the rich.NYC is different from much of the country. I&#x27;m not going to make an argument that it&#x27;s any better or any worse, but it is different. NYC congestion pricing as a national debate is missing the forest for the trees.

I think it&#x27;s because it disproportionately impacts the people who can least afford it. It allows the wealthy to continue to enjoy the convenience (relative to alternatives) of driving into the city while polluting and causing traffic at a price that has zero impact on their lives while it punishes those who already have much less and whose lives will be impacted by the fines and the often significant amounts of time they&#x27;ll have to spend arranging and taking alternative modes of transportation.That&#x27;s a very hard sell when people all around the country are feeling continuous downward pressure on their lifestyle and financial security while billionaires are seen getting massive tax breaks and pillaging everything they want while escaping accountability for the harms they cause everyone else. Taking a basic task like driving into the city, something many people are forced to do for work, and punishing them for it while once again giving the wealthy a pass was certain to upset people. in fact, by forcing more of the peasant class off the roads it makes driving into the city much more pleasant for the people with enough money to not care about the extra expense. Taking from the poor to improve things for the wealthy resonates with a lot of people.It also doesn&#x27;t help that in other contexts, congestion pricing has already hit people&#x27;s wallets and is seen as an exploitative business model designed to extract as much money from the public as possible. The last thing most people want is seeing congestion pricing and other price-fuckery infesting another aspect of their daily lives, which is why the pushback against wendy&#x27;s implementing it was so swift and severe that the company had to backpedal even after spending a small fortune on the digital menu boards they needed to enable it.

I&#x27;m curious how congestion pricing became a national issue. The strength of conviction people have about this policy–almost either way, but certainly among those against–seems to scale with distance from the city.Nobody in Idaho gets uppity about New Jersey&#x27;s tolls. But they have strong, knowledge-free, almost identity-defining opinions about congestion charges.Is it because it&#x27;s a policy that&#x27;s worked in Europe and Asia and is thus seen as foreign? Or because it&#x27;s New York doing it, so it&#x27;s branded as a tax, versus market-rate access or whatever we&#x27;d be calling it if this were done in Miami?

<a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC7314691&#x2F;figure&#x2F;f0025&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC7314691&#x2F;figure&#x2F;f002...</a>Take a look at their figure, especially in May 2020—the average appears lower, but, more significantly, there is much less variability in May 2020 compared to earlier years.The authors&#x27; model quite strongly includes their preferred confound (secular decrease in PM2.5) but doesn&#x27;t explore what other covariates could explain the differences between years.It&#x27;s fine to say that one should be skeptical, but one contrary report doesn&#x27;t invalidate an antecedent report, and the structure of a linear model strongly influences an outcome.

&quot;Not statistically significant&quot; doesn&#x27;t mean did not happen.Given the physical mechanisms involved it is implausible that pollution did not decline. And if you look at their data you see a marked drop in 2020 at day 70This is March 10 or thereabouts, I think. And there are ZERO high pm 2.5 days for a 20 day stretch or so. This isn&#x27;t seen in other years. The vast bulk of days are below the trend.And then for the rest of the year there are some days above the trend line but no high pm 2.5 days.This fits with people being extra cautious in the early days and then relaxing a bit as things went on.Now, I&#x27;m eyeballing this so I could be incorrect. But:1. The effect was found in other cities2. The physical mechanism makes it highly expected that there would be a dropThe study was about the slope of the regression modal, but if you had scrambled the years I&#x27;m fairly confident I could have picked 2020 out of the set.

That&#x27;s a very surprising finding since the drop in traffic was very noticeable. I wonder where the PM2.5 is coming from?

We have fruit trees in our backyard. The year of the COVID lockdown they had so much fruit the branches broke from the weight. Most fruit I&#x27;ve seen in 20 years in the house, by a large margin.

There was a study published about how much air pollution dropped in NYC during the COVID lockdown. PM2.5 was found to have dropped 36%. However with more robust analysis, this drop was discovered to not be statistically significant. I would caution anyone reading this who is tempted by confirmation bias.Source: <a href="https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC7314691&#x2F;" rel="nofollow">https:&#x2F;&#x2F;pmc.ncbi.nlm.nih.gov&#x2F;articles&#x2F;PMC7314691&#x2F;</a>

There&#x27;s a large (long time) movement to do this to lower Manhattan, the most public transit connected area in the US (probably North America, definitely up there in the world). It&#x27;s getting pick up again.

Isn&#x27;t times square already pedestrian?<a href="https:&#x2F;&#x2F;ny.curbed.com&#x2F;2017&#x2F;4&#x2F;19&#x2F;15358234&#x2F;times-square-snohetta-before-after-photos" rel="nofollow">https:&#x2F;&#x2F;ny.curbed.com&#x2F;2017&#x2F;4&#x2F;19&#x2F;15358234&#x2F;times-square-snohet...</a>

Big agree. Times Square would be a great place to start.

They should make pedestrian-only streets in most dense places of Manhattan and use these money to improve public transportation. Even just a few blocks of no cars would make a huge difference for livability of the city center.

I would really appreciate it if the Bay area got real congestion pricing and also enforcement. We have lots of HOT lanes here, but they are basically unenforced so everyone sets their ez-pass to “3” and gets the free HOV pricing, which rapidly becomes economical at the rate of enforcement in the Bay.Frankly, if they let me citizen report - I could likely cover my entire tax burden in 2-3 days. At $490&#x2F;ticket, the ROI for enforcement seems obviously there.

This article confirms my existing bias&#x2F;belief that user pays and auction[0] based systems improve governmental programs and finite supply systems in a society like the USA.[0]- Yes I&#x27;m well aware this is not an auction based system in this case.

&gt; You could, at the extreme, ban all motor vehicles but the opportunity cost would outweigh the benefitsWe did this in Times Square and on Broadway, and it&#x27;s honestly been great. I say this as someone who takes cars far more frequently than most New Yorkers and has a place I lived at full time for over a decade off one of those closed-off sections of Broadway.

Well, the market decides where the optimum is *in response to* the price set by the government. So the government can decide at least approximately where they want things to end up by setting a higher or lower price.

The point of congestion pricing is to let market mechanisms determine where the optimum is.

That&#x27;s a straw man. I didn&#x27;t say personal vehicles.

I wouldn&#x27;t assume your last claim.It could also be the case that making it viable to drive personal vehicles at all inside a dense city comes with opportunity costs (parking, roads that cut through infrastructure, pollution, noise) that aren&#x27;t worth it.And I&#x27;d wager that it is the case.

Since this is generating revenue for NYC, you can&#x27;t consider whether this tax is good or bad in a vacuum though. The alternatives are a different tax with its own effects, or more debt, or less spending. (In this case, the revenue goes to the MTA.) Any opportunity costs due to less traffic are at least partially offset by opportunity costs you aren&#x27;t having to pay somewhere else.

Dynamic pricing based on congestion would solve this. It would also almost certainly result in higher costs for drivers though.

Try things and ask the people in a year if they like the results, then do the good ones more and the bad ones less.

You take a walk along a 55-mph stretch of highway, and then you take a walk down Broadway, and you see which one makes you feel better as a human being.

It&#x27;s called congestion pricing because you can measure the opportunity cost.

Not surprising. The real question is how do we measure the opportunity cost of these measures? Is it a net gain? You could, at the extreme, ban all motor vehicles but the opportunity cost would outweigh the benefits.

all i gotta say is, super work, everyone!<a href="https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s41467-025-65127-x" rel="nofollow">https:&#x2F;&#x2F;www.nature.com&#x2F;articles&#x2F;s41467-025-65127-x</a>Now we can get back to our regularly scheduled global warming, without all those pesky clouds in the way.

congestion pricing is the gift that keeps giving

That was true at the beginning of congestion pricing and perhaps over the summer, but it is definitely not true anymore

21 minutes faster.<a href="https:&#x2F;&#x2F;www.tomtom.com&#x2F;newsroom&#x2F;explainers-and-insights&#x2F;the-data-behind-nyc-s-congestion-pricing-success&#x2F;" rel="nofollow">https:&#x2F;&#x2F;www.tomtom.com&#x2F;newsroom&#x2F;explainers-and-insights&#x2F;the-...</a>

No mention about change in average commute time?

The city does it for the benefit of the public, the Corp does it for the benefit of the shareholders

Congestion pricing == demand pricingYet it’s good if the city does it but bad if a Corp does it?

Interesting study. Similar results in London I heard.

I hate this distinctly American idea that no policy can cause any detriment to any disadvantaged people at all, even if the policy effects are incredibly income-progressive overall. This is how we end up with carveouts for every special interest group in every single policy, the populace justifying turnstile hopping, lack of traffic enforcement by police, opposition to speed and red light cameras, opposition to rezoning unless it&#x27;s built by free-range grass-fed vegan union labour and 100% below market, etc.

<a href="https:&#x2F;&#x2F;portal.311.nyc.gov&#x2F;article&#x2F;?kanumber=KA-03612" rel="nofollow">https:&#x2F;&#x2F;portal.311.nyc.gov&#x2F;article&#x2F;?kanumber=KA-03612</a>&gt; Some drivers can apply for Low-Income Discount or Low-Income Tax Credit for Residents.&gt; A 50% discount is available for low-income vehicle owners enrolled in the Low-Income Discount Plan (LIDP). This discount begins after the first 10 trips in a calendar month and applies to all peak period trips after that for the remainder of the calendar month.The revenue also goes towards public transit, and the congestion charge applies mainly to the wealthiest part of the wealthiest borough.

How does NYC congestion pricing deal with disparate impacts? Real question, I don&#x27;t live near NYC

Yea, if they could keep ALL of the poor people out, image how great that would be!

You know what else would drop pollution and ease traffic congestion?Allowing employees to work remote.

Some people are really going to hate this.

[dupe] <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=46213504">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=46213504</a>

&gt; Truckers were using lower manhattan as a cut-through route to other placesPopular truck route from Queens-&gt;Bronx was 59th st bridge, left onto 2nd then immediate left onto 59th, and another left onto 1st and take 1st all the way to Willis Ave bridge to beat the RFK bridge (formerly the Triborough) tolls.

the snark made me read the comment, I&#x27;ll admit it

It&#x27;s good to point this out but I don&#x27;t think the snarkiness at the beginning is necessary to get your point across.

To head off the almost inevitable recapitulation of yesterday&#x27;s parade of misinformed complaints by teenage libertarians, please actually read the paper before commenting. The paper shows there was no significant reduction in entries to the congestion charge zone by cars, vans, and light trucks. And you can confirm this conclusion is consistent with their source data using their github repo. The reduction in pollution is coming from the significant decline in heavy truck traffic. Truckers were using lower manhattan as a cut-through route to other places and they are now doing that less, exactly as congestion pricing planners long argued.

exactly. and the pandemic &quot;lockdowns&quot; showed those of us who actually live here that what we want is fewer cars in our neighborhoods.

that&#x27;s great. because those cars trash the city.

See also <a href="https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=46213504">https:&#x2F;&#x2F;news.ycombinator.com&#x2F;item?id=46213504</a>

There was also an endless parade of NY Post stories about how Manhattan restaurants would suffer because their customers couldn&#x27;t just drive in from Long Island and New Jersey.

Very few poor people drive into lower Manhattan. And people whose work requires them to drive in that area (delivery drivers, plumbers, etc.) come out ahead. One of the first NYT stories after congestion pricing was rolled out had multiple quotes from tradesmen reporting that they&#x27;re saving an hour or more a day and prefer the new system.

Im not sure this fits, they saw a much larger drop (18%) in heavy duty trucks entering the city, and a smaller drop (9%) in passenger cars. I am not sure the public transit options are close alternatives for heavy duty trucks.

For many people, the thing being substituted for an alternative is not &quot;transportation into Manhattan&quot;, but more broadly &quot;engaging in commerce in Manhattan&quot;

The question becomes how critical is X and is there a close alternative. In this case I&#x27;d say for 95% of people yes driving is easily substituted by NYC&#x27;s public transit options.

IMO it would be even better if was an auction based system, maybe 24&#x2F;7. That way if someone has an &lt;= $8.99 threshold&#x2F;need to drive, and they find a slot, they will. I think the static pricing will create a distortion in the usage, maybe having dynamic pricing (with a ceiling) would be smarter?

Even without congestion pricing, the poor are the least likely to drive. Spending public money to subsidize driving (which we’re still doing on balance, even in Manhattan) disproportionately helps the wealthy.

Because it&#x27;s economically infeasible to drive?

working class people are predominantly using public transit to get around nycthis claim has been debunked many times and anyone with eyes can see who the private drivers in NYC are

This fits the template in the post you&#x27;re replying.

Driving (and more importantly, parking) in NYC was never that much of a poor person thing.

You think it was primarily poor people who were driving their cars into Midtown?

That’s two new accounts claiming to be worried about the poor. We could use congestion pricing in these kinds of threads.

OR it encourages people to walk to transit which ALSO has positive side health benefits.

Pigouvian*, this is a regressive tax though that is probably unnecessary as the other studies referenced or linked in this thread show.

Of course they work. If the government manipulates the equation to make something unaffordable, the poor can no longer afford it. That’s not the point.

Pigovian taxes WORK, and are in many cases desirable, something lolberts just seem unable to get their heads around.

Who&#x27;s &quot;they&quot; here? I don&#x27;t think it&#x27;s the government forcing everyone at finance and tech companies to come into the office.

Imagine it actually mattered to them and they didn&#x27;t force everyone into downtown offices instead of allowing people to work from home. This is a cash grab.

This doesn&#x27;t change my argument at all.The more money you have, more you benefit from this ruling. Now you can buy a service which was not possible before.

NYC has 8M people and 2M cars. Manhattan has like a 22% car ownership rate, and it&#x27;s… not the poor people. <a href="https:&#x2F;&#x2F;www.hunterurban.org&#x2F;wp-content&#x2F;uploads&#x2F;2024&#x2F;06&#x2F;Car-Light-NYC-Infographics-May-2024.pdf" rel="nofollow">https:&#x2F;&#x2F;www.hunterurban.org&#x2F;wp-content&#x2F;uploads&#x2F;2024&#x2F;06&#x2F;Car-L...</a>A parking spot will cost you more than rent in some other cities.

Because that’s not true. Cars are expensive compared to transit everywhere, but especially so in NYC. This was studied a lot before congestion pricing was implemented and only something like 2% of poor people were going to pay congestion charges. This did not stop a bunch of rich suburbanites from using them as a prop to demand that the city subsidize their lifestyle at the expense of NYC taxpayers, of course.<a href="https:&#x2F;&#x2F;www.cssny.org&#x2F;news&#x2F;entry&#x2F;the-cost-of-killing-congestion-pricing" rel="nofollow">https:&#x2F;&#x2F;www.cssny.org&#x2F;news&#x2F;entry&#x2F;the-cost-of-killing-congest...</a>

&gt; curious why no one is discussing this but this is basically a middle finger for poor peopleBecause the poor don’t drive in New York, and to the extent they do, they likely qualify for an exemption.

I don&#x27;t think poor people who lived in NYC were driving that often anyway? cars are expensive to begin with and parking is crazy in that part of the city

&gt; and often the better optionEven before congestion pricing this was the major factor. It&#x27;s often quicker, more reliable, more pleasant, and has less variation in delays to ride the train&#x2F;subway in NYC. Speaking from personal experience I could easily eat the congestion charge to daily commute into Manhattan, and I&#x27;d rather still take the train because I can do my mindless scrolling or read a book during that time.The only time I&#x27;ve found that a car is better is during the weekends with a group larger than about 4 people. The train schedules are terrible, the commute time isn&#x27;t bad, and the price per ticket (assuming you&#x27;re coming from the outer suburbs) vs parking and tolls works out to be a wash.

You are assuming a car is required.The whole issue with car dependency is that it is a massive barrier for participating in society.Public transit is orders of magnitude cheaper, and very viable and often the better option in the New York area.

Whats concern trolling?This mechanism allows people with more money to enjoy driving in the city or is this congestion prcing based on your salary? no its not its based on the time in the city independent of what you make.A person with their high end car and miillions now can buy himself a nice little drive into the city while everyone else can&#x27;t.

Maybe nobody should be driving a car in an urban core? Baby steps...

you clearly dont live here or you&#x27;d know that the poor of NYC are not the ones that own cars. they&#x27;re the ones that take public transit. also, there are state benefits that offset congestion pricing and other fees for people who are poor

the only poor people driving personal cars in manhattan are projects residents with their taxpayer-subsidized parking spot

&quot;poor&quot; is relative. Ever thought about this?Should i said poorer people who still need a car to drive in NYC to make it more understandable to the hn crowed Oo?!

And yes let’s think of the poor people who have no choice but to drive into Midtown and downtown for work.Have you ever talked to poor people in NYC?

Im curious why no one is discussing this but this is basically a middle finger for poor people.Rich people now have a great way to continue driving their cars, everyone else is fucked?

JFK has a subway station (Howard Beach)EWR is in New Jersey, so... not technically the NYC Subway. But taking the subway to Penn Station, then hopping on NJ Transit is pretty easyLGA is the only one that straight up has no subway&#x2F;train option.

They should put subway stations in each of the 3 big airports.

Not necessarily. I use my brake far more in stop and start traffic on the highway than I do in Manhattan.In the city stop and start is primarily determined by traffic lights, which are predictable, rather than the traffic itself.

&gt; but I guess more pollution added up to the surrounding borroughs in addition to more trafficWhy? Fewer cars into Manhattan means fewer cars through the boroughs. And even if they all diverted, you’re still looking at less idling and less stop and start braking.

The article speaks to this as well, &quot;Pricing led to a drop in pollution across the greater metropolitan area, according to the study, published in the journal npj Clean Air.&quot;So while this was&#x2F;is a common sentiment about congestion pricing, looks like it luckily didn&#x27;t pan out.

The study found the opposite: people are picking healthier choices throughout the region. This makes sense: if you switch to taking the train, in addition to not driving in the congestion zone you also aren’t driving the distance between the closest train station and Manhattan, which for many people will be more engine operating time than they spend in the zone itself.

Good question, this happened in London for sure, congestion charging increased the net pollution from vehicles but reduced the metrics inside the city, probably not much either way.

This was a common anti-congestion pricing talking point, but it ends up not being the case. People either don&#x27;t drive into the city, or they take transit.

It may have dropped pollution in Manhattan but I guess more pollution added up to the surrounding borroughs in addition to more traffic.

&gt; Once the Feds approved the plan the State of NY made fixed, increasing, revenue targets their only goal.The first thing the State of NY did with congestion pricing was halt the plan (arguably illegally) before reintroducing it six months later with a price reduction to $9 down from $15: <a href="https:&#x2F;&#x2F;www.theguardian.com&#x2F;us-news&#x2F;2024&#x2F;nov&#x2F;14&#x2F;congestion-pricing-nyc" rel="nofollow">https:&#x2F;&#x2F;www.theguardian.com&#x2F;us-news&#x2F;2024&#x2F;nov&#x2F;14&#x2F;congestion-p...</a>

&gt; If they cared about emissions they could try to regulate idling...They have, for decades. <a href="https:&#x2F;&#x2F;nyc-business.nyc.gov&#x2F;nycbusiness&#x2F;description&#x2F;idling-regulations" rel="nofollow">https:&#x2F;&#x2F;nyc-business.nyc.gov&#x2F;nycbusiness&#x2F;description&#x2F;idling-...</a>

&gt; NY dropped the goals of cleaner air and any premise of regulating traffic flowWhat’s your source for this?Also, why would a goal matter more than results?

&gt; try to regulate idling, which worse emissions profilesMost certainly regulated. There are people who make a living off of reporting idling trucks and collecting the bounty.

&gt;If they cared about emissions they could try regulating idling, which worse emissions profilesThey do, in fact, regulate idling my dude-
<a href="https:&#x2F;&#x2F;portal.311.nyc.gov&#x2F;article&#x2F;?kanumber=KA-02222" rel="nofollow">https:&#x2F;&#x2F;portal.311.nyc.gov&#x2F;article&#x2F;?kanumber=KA-02222</a>&gt; In New York City, vehicle idling is illegal if it lasts more than 3 minutes or more than 1 minute when adjacent to a school.

NY dropped the goals of cleaner air and any premise of regulating traffic flow. Once the Feds approved the plan the State of NY made fixed, increasing, revenue targets their only goal. If they cared about emissions they could try to regulate idling, which worse emissions profiles. Here in NYC they do this money making charade of &quot;street sweeping&quot; for 90 min twice or more times a week. And people sit in their cars with tge engine running that whole time. It too is focused on revenue, though they do actually mechanically sweep the street sides.

Didn&#x27;t advocate for &quot;more highways&quot; -- I totally get it. More offering that maybe these problems shouldn&#x27;t be viewed as a purely zero-sum game, where cities get all the benefit at the expense of the larger region due to a form of geographic tyranny. (Or at least, perhaps we shouldn&#x27;t pretend that externalities don&#x27;t exist through studies that largely look at quality-of-life factors in the hub.)You can see some of these same dynamics playing out in SF with the decommissioning of the &#x27;Great Highway&#x27; on the west side, which led to a recent recall of the local council member. Why does the majority vote of a city of 800k people get to unilaterally dictate the transportation options for a region upwards of 7MM?

&gt; when you decommission historical arteriesThere are no highway arteries running through the congestion zone. Building one would require hundreds of billions of dollars of eminent domain.Manhattan has a $1tn GDP [1], on par with Switzerlad [2]. Its economy is larger than all but 6 states (between Pennsylvaia and Ohio) [3]. More than all of New Jersey. If it crossed the pond it would be the fifth-largest member of the EU, between the Netherlands and Poland [4].It&#x27;s a tremendously productive jewel that towers–literally–over the economies of its neighbors. Sacrificing Manhattan to save a few bucks on a trucker who doesn&#x27;t want to take a highway through the Bronx is absolutely mental from a social, economic and environmental perspective.[1] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Economy_of_New_York_City" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Economy_of_New_York_City</a> $939bn in 2023[2] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;List_of_countries_by_GDP_(nominal)" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;List_of_countries_by_GDP_(nomi...</a>[4] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Economy_of_the_European_Union" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Economy_of_the_European_Union</a>[3] <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;List_of_U.S._states_and_territories_by_GDP" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;List_of_U.S._states_and_territ...</a>

I understand what you&#x27;re saying but after 100 years of uninhibited car-centric design i think its reasonable for those of us who live here to want to prioritize the experience of people who live and work in manhattan, south bronx, and west queens and brooklyn. if people want to commute from places surrounding the city in a more efficient fashion i think its reasonable for them to redress that with the local or state governments instead of using nyc infrastructure for free in a way that inhibits community growth here.

The Verazano is already more expensive than congestion pricing. It&#x27;s cheaper to drive to Manhattan from Jersey than Brooklyn via Staten Island. Never heard any Jersey driver complain though.

&gt; it&#x27;s somewhat inevitable that the network get snarled.Is this happening in&#x2F;around NYC?&gt; Sure, I&#x27;ll &#x27;just take public transport&#x27; to go downtown, but the options significantly diminish if I want to travel from North Bay to South Bay to see my parents, or Jersey to South Brooklyn to visit my inlaws.The are the same, you just have to pay the fee.Also, for like 90% of NJ you&#x27;d be going the southern route into Brooklyn anyway, no congestion pricing involved.

Both NY and SF were regional hubs before cars disfigured them. No commercial vehicle is going to be discouraged by a $10 dollar charge, and trade is so much easier when the roads aren&#x27;t clogged by single people demanding 1000 sq-ft of ground space to move around.

It doesn&#x27;t seem reasonable to complain that multitudes more of people should substantially worsen their everyday trips and suffer much higher risk of being killed by cars to make occasional trips that would pass through the city more convenient.

&gt; the options significantly diminish if I want to travel from North Bay to South Bay to see my parents, or Jersey to South Brooklyn to visit my inlaws.This is a fixable problem. I&#x27;m still waiting on someone to do it though. NY is mostly interested in corruption from their preferred interests. (which is why they are working on a law to require a conductor on all subways instead of working to eliminate all that extra labor, instead of fixing their system so it is fast and reliable and then covers more area)

What you&#x27;re describing as a problem is actually the solution, and what you think is the solution is actually the problem.Highways running straight through the middle of major cities is stupid, unnecessary, and harmful. Going to the major cities is fine, but there&#x27;s no good reason they need to go all the way through them. They should just go around&#x2F;near the cities instead.

Manhattan is surrounded by a ring road. It is excluded from congestion pricing.

One thing that irks me about these schemes is that they often ignore cities role as regional hubs -- i.e. many cities became cities because they serve as geographical gateways interlocking the surrounding region. They are happy to take the benefits of being at the hub, but (increasingly) adopt a nativistic dialogue with the rest of the spokes.I get that no one likes highways running through their communities, but when you decommission historical arteries while aggressively adopting anti-car transportation policies throughout the rest of the hub, it&#x27;s somewhat inevitable that the network get snarled.Maybe congestion pricing is the way to go -- it can certainly work for major European cities built inland, and surrounded by ring roads. For NYC &#x2F; SF (surrounded by water), I&#x27;m less convinced. Sure, I&#x27;ll &#x27;just take public transport&#x27; to go downtown, but the options significantly diminish if I want to travel from North Bay to South Bay to see my parents, or Jersey to South Brooklyn to visit my inlaws.

In New York City, congestion pricing leads to marked drop in pollution

A “frozen” dictionary for Python

Size of Life

OP here.I built this because I recently caught myself almost pasting a block of logs containing AWS keys into Claude.The Problem: I need the reasoning capabilities of cloud models (GPT&#x2F;Claude&#x2F;Gemini), but I can&#x27;t trust myself not to accidentally leak PII or secrets.The Solution: A Chrome extension that acts as a local middleware. It intercepts the prompt and runs a local BERT model (via a Python FastAPI backend) to scrub names, emails, and keys before the request leaves the browser.A few notes up front (to set expectations clearly):Everything runs 100% locally.
Regex detection happens in the extension itself.
Advanced detection (NER) uses a small transformer model running on localhost via FastAPI.No data is ever sent to a server.
You can verify this in the code + DevTools network panel.This is an early prototype.
There will be rough edges. I’m looking for feedback on UX, detection quality, and whether the local-agent approach makes sense.Tech Stack:
 Manifest V3 Chrome Extension
 Python FastAPI (Localhost)
 HuggingFace dslim&#x2F;bert-base-NER
 Roadmap &#x2F; Request for Feedback:
Right now, the Python backend adds some friction. I received feedback on Reddit yesterday suggesting I port the inference to transformer.js to run entirely in-browser via WASM.I decided to ship v1 with the Python backend for stability, but I&#x27;m actively looking into the ONNX&#x2F;WASM route for v2 to remove the local server dependency. If anyone has experience running NER models via transformer.js in a Service Worker, I’d love to hear about the performance vs native Python.Repo is MIT licensed.Very open to ideas suggestions or alternative approaches.

Show HN: Local Privacy Firewall-blocks PII and secrets before ChatGPT sees them

An Orbital House of Cards: Frequent Megaconstellation Close Conjunctions

Disney making $1B investment in OpenAI, will allow characters on Sora AI

Hi HN,I built WhatHappened (whathappened.tech) because I have a love&#x2F;hate relationship with this site. I love the content, but the &quot;wall of text&quot; UI gives me FOMO. I was spending too much time clicking into vague titles (&quot;Project X&quot;) or wading through flame wars just to find technical insights.I built this tool to act as a filter. It generates a card for the top daily posts with a few specific features to cut the noise:1. AI Summaries: It generates a technical TL;DR (3 bullet points) and an ELI5 version for every post.2. The Heat Meter: I analyze the comment section to visualize the distribution: Constructive vs. Technical vs. Flame War. If a thread is 90% Flame War, I know to skip it (or grab popcorn).3. Contrarian Detection: To break the echo chamber, the AI specifically hunts for the most upvoted disagreement or critique in the comments and pins it to the card.4. Mobile-First PWA: I mostly read HN on my phone, so I designed this as a PWA. It supports swipe gestures and installs to the home screen without an app store.Stack: Next.js, Gemini, Supabase.It currently supports English and Chinese. Any feedback will be appreciated! My original X post: <a href="https:&#x2F;&#x2F;x.com&#x2F;marsw42&#x2F;status&#x2F;1997087957556318663" rel="nofollow">https:&#x2F;&#x2F;x.com&#x2F;marsw42&#x2F;status&#x2F;1997087957556318663</a>, please share if you like it or find it helpful! :DThanks!

Show HN: WhatHappened – HN summaries, heatmaps, and contrarian picks

Oldest attestation of Austronesian language: Đông Yên Châu inscription

Getting a Gemini API key is an exercise in frustration

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i always loved looking up the On-Line Encyclopedia of Integer Sequences (OEIS) when researching a sequence of numbers.so I decided to make a TUI and CLI for it so that I can browse sequences in the terminal.it supports almost all the features on the site (including the OEIS Webcam) and supports graphs, a preview pane, exporting and bookmarks.more features here:
<a href="https:&#x2F;&#x2F;github.com&#x2F;hako&#x2F;oeis-tui?tab=readme-ov-file#features" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;hako&#x2F;oeis-tui?tab=readme-ov-file#features</a>repo:
<a href="https:&#x2F;&#x2F;github.com&#x2F;hako&#x2F;oeis-tui" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;hako&#x2F;oeis-tui</a>gitHub releases:
<a href="https:&#x2F;&#x2F;github.com&#x2F;hako&#x2F;oeis-tui&#x2F;releases" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;hako&#x2F;oeis-tui&#x2F;releases</a>cargo:
cargo install oeis-tui