7 ms·

In Shenzhen for a tech meeting. The streetscape is quieter, despite high traffic levels and I hear not only MORE birdsong, but the birds do more complex songlin

In Shenzhen for a tech meeting. The streetscape is quieter, despite high traffic levels and I hear not only MORE birdsong, but the birds do more complex songlines. The air is clean. For sure some of this is because it's a coastal city and has fresh sea breezes, but I've been in other Chinese coastal cities in times past and the air was significantly less clean. There are social upsides for an almost-all-EV city. This is an 18m person city. It's not exclusively wealthy people, its just a city with a very high local EV population and it shows.

krustyburger 7mo ago
Surely you don’t think birds have evolved to sing more complex songs in the time since mass EV adoption?
- 0_____0 7mo ago
  Birds adapt their song to ambient noise conditions. This paper [1] studies the Pearl River Delta (where Shenzhen is) as a natural experiment. It shows spectral changes in the target species correlating to background noise levels. I haven't looked hard enough to make sure there isn't a study that does find complexity changes but it's certainly clear that noise can affect bird song behavior generally. [1] https://www.sciencedirect.com/science/article/pii/S2351989421002456 https://www.sciencedirect.com/science/article/pii/S235198942...
toast0 7mo ago
> I hear not only MORE birdsong, but the birds do more complex songlines. Do the local mockingbirds sing the song of the car alarm? That one is pretty complex.
tlogan 7mo ago
We must not be visiting the same city.
jesterson 7mo ago
>almost-all-EV city. Shenzhen is not nearly "almost-all EV" city. There is a lot of wealthy people and almost none of them drives EV. You can see all expensive cars are ICE (blue plates). Modern ICE cars emit almost no sound or emissions. Its not 70s with black smoke coming from exhaust pipes. You can take any densely populated city with almost none EV vehicles (say Tokyo) and you can hear birds and air would be very clean.
- shiroiuma 7mo ago
  I live in Tokyo, and the air is not that clean close to highways: large diesel trucks pollute a lot, and also small motorbikes/scooters pollute horribly because they don't seem to require any emissions controls at all. The main thing keeping the air clean here is the proximity to the bay, along with the fact that there just aren't that many private cars in the first place, since most people take public transit and don't drive because there's nowhere to park.
  - jesterson 7mo ago
    Large trucks do not pollute a lot (there are strict standards to that matter). While they do pollute obviously, there is no viable substitute to it. EV truck is a dream at this point in history. Amount of private cars in Tokyo is huge. Pollution near expressways in rural japan far from bays is next to nothing, so having it close to ocean does help a little. Small motorbike/scooters are not allowed on expressways.
    - dalyons 7mo ago
      > EV truck is a dream at this point in history. you should tell china. https://www.electrive.com/2026/01/23/year-end-surge-electric-trucks-outsell-diesel-for-the-first-time-in-china/ https://www.electrive.com/2026/01/23/year-end-surge-electric...
spookybones 7mo ago
Mexico City needs this badly. It would be beautiful if it wasn't for the smog and noise of traffic.
- peab 7mo ago
  I'm sure it's coming. I'm in Mexico this week and was surprised to drive by not one but two chinese car dealerships. Looks like almost 10% of cars sold last year were EVs
- kjkjadksj 7mo ago
  Inversion layer there will still trap ev particulate unfortunately
  - badc0ffee 7mo ago
    What is EV particulate? Like brake or tire dust?
    - sathackr 7mo ago
      yes. it's an argument that since EVs are heavier than fossil-fuel vehicles due to their batteries, that they generate more particulate emissions (brakes/tire dust) than fossil-fuel vehicles. it's a wrong argument, but it's still circulated in groups of factually-challenged people
      - globular-toast 7mo ago
        Nobody said they generate more but simply that they generate some. Modern petrol engines output very little particulates so almost all the particulates are from tyres and brakes. Why would EVs produce any less?
        seanmcdirmid 7mo ago
        While EVs are heavier—increasing tire wear—their regenerative braking significantly reduces brake dust, and they eliminate tailpipe exhaust entirely. Overall, EVs offer a net reduction in particulates.
direwolf20 7mo ago
[flagged]
- thehappypm 7mo ago
  Universities
  - direwolf20 7mo ago
    Are you sure?
    - shiroiuma 7mo ago
      For now, but they're catching up quickly I'm sure, esp. since American university quality is surely degrading quickly.
  - dagmx 7mo ago
    What do you base that on? Some of the best names in academia are Chinese, and in the computer graphics world, SIGGRAPH Asia has largely eclipsed SIGGRAPH for academic presentations
    - kortilla 7mo ago
      Chinese names at American universities
      - dagmx 7mo ago
        Not unless they’re going right back to China. In droves.
- hedora 7mo ago
  [flagged]
- mayama 7mo ago
  Liberal arts, Hollywood and the associated soft power, increasingly prevalent onlyf___ etc.
skeeter2020 7mo ago
It also has a relatively low vehicle density, roughly 1/3 of somewhere like Houston. Mexico City is a good comparison by size and vehciles, but is also a way older, sprawling city. Shenzhen was largely built around modern road planning and extensive transit, and the power of aggressive policies limiting gas cars.
Markoff 7mo ago
Counterpoint - I returned to China (Beijing) last summer after 9 years and was honestly surprised how LITTLE it has changed over those 9 years, I was expecting big changes reading this tales about Shenzhen, but the reality is maybe only 1/4-1/3 of the cars on the road were EVs, there were pretty much none escooters, people still smoke in restaurants and yes, the air was for the most part perfectly fine, though this was really case in summer even before. The most noticable change which puzzled me where those big boxes with slots in all restaurants and grocery shops, which are rental powerbanks. Other than these hardly anything changed, policemen in police station smoked right under no smoking sign and in that half an hour in their office I inhaled more secondary smoke than in years in Europe combined. To their credit they were as laid back as policemen in my small home town. Beijing province border checks are more strict, but they still let us go without registered accommodation on weekend. Oh yeah, out of dozens restaurants we frequented ONE fancy hot pot restaurant had robot bringing over plates. Plus Taobao/Tmall seems replaced now with Pinduoduo with super cheap purchases (think double the Alibaba/factory price) including free shipping. Mutianyu great wall is now fully mainstream, everyone (99%) now use cable car instead of hiking uphill, before it felt at least 50:50, people got lazy. Ah yeah, everywhere you go you need to present passport and sometimes also book ticket in advance, so from tourist standpoint it's worse, before you could just show up same visit major sights in Beijing even without passport.
- DiogenesKynikos 7mo ago
  1/4-1/3 EVs is an underestimate for somewhere like Shenzhen (probably for Beijing too). It's going to be well over 50% there. And virtually all scooters will be electric. You're right about the smoking, though. It's a massive problem.
  - Markoff 7mo ago
    it's definitely not underestimate for Beijing where I stayed for 3 weeks this summer, maybe you count PHEV as EVs, many of those cars which look like EVs are actually hybrids, only in late 2025 China reached 50% newly registered BEV+PHEV cars plus there are lots of previously registered cars and if we count only BEVs the percentage will be much smaller, actually I think 1/3 of BEV on the road is quite an overestimate from my side are NEV common? sure. do BEV make majority of cars on the road? for sure not there are basically none scooters, they use either (e)bikes or electric motorbikes/mopeds (these are not new, they used them en masse already 10 years ago)
Foobar8568 7mo ago
Considering how polluted was HK, hearing that Shenzhen is less polluted and quieter makes me happy. True enough, the last time I have been in HK I was surprised to see less smog and overall less pollution.
- deleted 7mo ago
  [deleted]
simianparrot 7mo ago
What about the increased pollution from road dust? In Norway this has led to higher pollution levels that are directly dangerous to people and animals than back when we were all combustion vehicles. The heavier EV's are causing genuinely harmful particles simply by driving on the roads themselves.
- fraboniface 7mo ago
  Thats' why you need light EVs. Norway has electric tanks. China has light EVs.
- zarzavat 7mo ago
  This sounds like a nice problem to have. Most of the world lives cities blighted by ICE pollution.
- Tepix 7mo ago
  On the other hand the EVs produce no exhausts and less harmful particles from using their brakes.
- andriamanitra 7mo ago
  Where did you get the idea that EVs have caused it? As far as I know the amount of road dust from EVs is within the same ballpark so the claim that it has led to overall higher pollution levels sounds inconceivable. I can't even find sources that indicate high pollution levels in Oslo besides a Bloomberg article that says the situation has actually improved in recent years. [1] On the contrary Oslo seems to be doing comparatively well according to the air quality data from iqair. [2] [1] https://www.bloomberg.com/news/articles/2025-04-11/why-oslo-s-dirty-air-persists-despite-rise-of-electric-vehicles https://www.bloomberg.com/news/articles/2025-04-11/why-oslo-... [2] https://www.iqair.com/us/norway/oslo/oslo https://www.iqair.com/us/norway/oslo/oslo
- alex_duf 7mo ago
  This claim keeps circulating around and around and is not "EVs are producing more pollution", it's "if EVs are going at motorway speed, and if we only look at the pollution generated by the tires, then indeed they produce a little more". But that's completely ignoring tailpipe emission, and the fact that in an urban setting it's still vastly more advantageous to drive an EV. See https://doi.org/10.1016/j.trd.2025.104622 https://doi.org/10.1016/j.trd.2025.104622
RataNova 7mo ago
It's not just a "rich city" effect. That's kind of the key point in the whole EV debate... once it's mainstream and infrastructure is there, it stops being a luxury signal and just becomes… normal urban life, with some pretty noticeable side benefits
Vinnl 7mo ago
AFAIK, beyond a certain speed (~25km/h?), EVs make just as much noise as ICEs, since the noise is then mainly generated by the tyres hitting the road. So I'm somewhat sceptical about this claim. Dutch city centres can be really crowded and yet actually quiet, because there are practically no cars. It's probably not Shenzen-level crowded, but I'd bet that the number of people that are being transported at busy locations isn't too far behind. (As popular slogan is "cities aren't noisy, cars are noisy".)
- Dumblydorr 7mo ago
  Source? That sounds dubious. Here in USA you hear blazing engines constantly, I’m skeptical a rubber tire is louder than that
  - Vinnl 7mo ago
    The source is "I heard that somewhere", hence "AFAIK". It kinda matches my experience at least when I get closer to a highway, the noise I hear doesn't sound like engine noise anymore.
    - Mawr 7mo ago
      Yeah, but you probably don't walk along a highway every day to get your groceries, do you. The closer the traffic gets to where people live, the lower the speed limit, and the more relevant the loudness of an engine. Another factor is that an EV has a noise ceiling, whereas an ICE can get arbitrarily loud — think motorcycles, buses, trucks. ICEs also use all of their noise range all the time — revving, accelerating. Sudden harsh noise changes like that are much more noticeable and annoying than the sound of a theoretical steady-state ICE engine.
      - Vinnl 7mo ago
        Unfortunately the steady background noise of cars I do hear around my house (and thus where I get groceries) mostly comes from the highway. But you're right, in the city centre it's partially this quiet because it's about the farthest you can get from the highway.

krustyburger 7mo ago

Surely you don’t think birds have evolved to sing more complex songs in the time since mass EV adoption?

0_____0 7mo ago
Birds adapt their song to ambient noise conditions. This paper [1] studies the Pearl River Delta (where Shenzhen is) as a natural experiment. It shows spectral changes in the target species correlating to background noise levels. I haven't looked hard enough to make sure there isn't a study that does find complexity changes but it's certainly clear that noise can affect bird song behavior generally. [1] https://www.sciencedirect.com/science/article/pii/S2351989421002456 https://www.sciencedirect.com/science/article/pii/S235198942...

toast0 7mo ago

> I hear not only MORE birdsong, but the birds do more complex songlines. Do the local mockingbirds sing the song of the car alarm? That one is pretty complex.

tlogan 7mo ago

We must not be visiting the same city.

jesterson 7mo ago

>almost-all-EV city. Shenzhen is not nearly "almost-all EV" city. There is a lot of wealthy people and almost none of them drives EV. You can see all expensive cars are ICE (blue plates). Modern ICE cars emit almost no sound or emissions. Its not 70s with black smoke coming from exhaust pipes. You can take any densely populated city with almost none EV vehicles (say Tokyo) and you can hear birds and air would be very clean.

shiroiuma 7mo ago
I live in Tokyo, and the air is not that clean close to highways: large diesel trucks pollute a lot, and also small motorbikes/scooters pollute horribly because they don't seem to require any emissions controls at all. The main thing keeping the air clean here is the proximity to the bay, along with the fact that there just aren't that many private cars in the first place, since most people take public transit and don't drive because there's nowhere to park.
- jesterson 7mo ago
  Large trucks do not pollute a lot (there are strict standards to that matter). While they do pollute obviously, there is no viable substitute to it. EV truck is a dream at this point in history. Amount of private cars in Tokyo is huge. Pollution near expressways in rural japan far from bays is next to nothing, so having it close to ocean does help a little. Small motorbike/scooters are not allowed on expressways.
  - dalyons 7mo ago
    > EV truck is a dream at this point in history. you should tell china. https://www.electrive.com/2026/01/23/year-end-surge-electric-trucks-outsell-diesel-for-the-first-time-in-china/ https://www.electrive.com/2026/01/23/year-end-surge-electric...

spookybones 7mo ago

Mexico City needs this badly. It would be beautiful if it wasn't for the smog and noise of traffic.

peab 7mo ago
I'm sure it's coming. I'm in Mexico this week and was surprised to drive by not one but two chinese car dealerships. Looks like almost 10% of cars sold last year were EVs
kjkjadksj 7mo ago
Inversion layer there will still trap ev particulate unfortunately
- badc0ffee 7mo ago
  What is EV particulate? Like brake or tire dust?
  - sathackr 7mo ago
    yes. it's an argument that since EVs are heavier than fossil-fuel vehicles due to their batteries, that they generate more particulate emissions (brakes/tire dust) than fossil-fuel vehicles. it's a wrong argument, but it's still circulated in groups of factually-challenged people
    - globular-toast 7mo ago
      Nobody said they generate more but simply that they generate some. Modern petrol engines output very little particulates so almost all the particulates are from tyres and brakes. Why would EVs produce any less?
      - seanmcdirmid 7mo ago
        While EVs are heavier—increasing tire wear—their regenerative braking significantly reduces brake dust, and they eliminate tailpipe exhaust entirely. Overall, EVs offer a net reduction in particulates.

direwolf20 7mo ago

[flagged]

thehappypm 7mo ago
Universities
- direwolf20 7mo ago
  Are you sure?
  - shiroiuma 7mo ago
    For now, but they're catching up quickly I'm sure, esp. since American university quality is surely degrading quickly.
- dagmx 7mo ago
  What do you base that on? Some of the best names in academia are Chinese, and in the computer graphics world, SIGGRAPH Asia has largely eclipsed SIGGRAPH for academic presentations
  - kortilla 7mo ago
    Chinese names at American universities
    - dagmx 7mo ago
      Not unless they’re going right back to China. In droves.
hedora 7mo ago
[flagged]
mayama 7mo ago
Liberal arts, Hollywood and the associated soft power, increasingly prevalent onlyf___ etc.

skeeter2020 7mo ago

It also has a relatively low vehicle density, roughly 1/3 of somewhere like Houston. Mexico City is a good comparison by size and vehciles, but is also a way older, sprawling city. Shenzhen was largely built around modern road planning and extensive transit, and the power of aggressive policies limiting gas cars.

Markoff 7mo ago

Counterpoint - I returned to China (Beijing) last summer after 9 years and was honestly surprised how LITTLE it has changed over those 9 years, I was expecting big changes reading this tales about Shenzhen, but the reality is maybe only 1/4-1/3 of the cars on the road were EVs, there were pretty much none escooters, people still smoke in restaurants and yes, the air was for the most part perfectly fine, though this was really case in summer even before. The most noticable change which puzzled me where those big boxes with slots in all restaurants and grocery shops, which are rental powerbanks. Other than these hardly anything changed, policemen in police station smoked right under no smoking sign and in that half an hour in their office I inhaled more secondary smoke than in years in Europe combined. To their credit they were as laid back as policemen in my small home town. Beijing province border checks are more strict, but they still let us go without registered accommodation on weekend. Oh yeah, out of dozens restaurants we frequented ONE fancy hot pot restaurant had robot bringing over plates. Plus Taobao/Tmall seems replaced now with Pinduoduo with super cheap purchases (think double the Alibaba/factory price) including free shipping. Mutianyu great wall is now fully mainstream, everyone (99%) now use cable car instead of hiking uphill, before it felt at least 50:50, people got lazy. Ah yeah, everywhere you go you need to present passport and sometimes also book ticket in advance, so from tourist standpoint it's worse, before you could just show up same visit major sights in Beijing even without passport.

DiogenesKynikos 7mo ago
1/4-1/3 EVs is an underestimate for somewhere like Shenzhen (probably for Beijing too). It's going to be well over 50% there. And virtually all scooters will be electric. You're right about the smoking, though. It's a massive problem.
- Markoff 7mo ago
  it's definitely not underestimate for Beijing where I stayed for 3 weeks this summer, maybe you count PHEV as EVs, many of those cars which look like EVs are actually hybrids, only in late 2025 China reached 50% newly registered BEV+PHEV cars plus there are lots of previously registered cars and if we count only BEVs the percentage will be much smaller, actually I think 1/3 of BEV on the road is quite an overestimate from my side are NEV common? sure. do BEV make majority of cars on the road? for sure not there are basically none scooters, they use either (e)bikes or electric motorbikes/mopeds (these are not new, they used them en masse already 10 years ago)

Foobar8568 7mo ago

Considering how polluted was HK, hearing that Shenzhen is less polluted and quieter makes me happy. True enough, the last time I have been in HK I was surprised to see less smog and overall less pollution.

deleted 7mo ago
[deleted]

simianparrot 7mo ago

What about the increased pollution from road dust? In Norway this has led to higher pollution levels that are directly dangerous to people and animals than back when we were all combustion vehicles. The heavier EV's are causing genuinely harmful particles simply by driving on the roads themselves.

fraboniface 7mo ago
Thats' why you need light EVs. Norway has electric tanks. China has light EVs.
zarzavat 7mo ago
This sounds like a nice problem to have. Most of the world lives cities blighted by ICE pollution.
Tepix 7mo ago
On the other hand the EVs produce no exhausts and less harmful particles from using their brakes.
andriamanitra 7mo ago
Where did you get the idea that EVs have caused it? As far as I know the amount of road dust from EVs is within the same ballpark so the claim that it has led to overall higher pollution levels sounds inconceivable. I can't even find sources that indicate high pollution levels in Oslo besides a Bloomberg article that says the situation has actually improved in recent years. [1] On the contrary Oslo seems to be doing comparatively well according to the air quality data from iqair. [2] [1] https://www.bloomberg.com/news/articles/2025-04-11/why-oslo-s-dirty-air-persists-despite-rise-of-electric-vehicles https://www.bloomberg.com/news/articles/2025-04-11/why-oslo-... [2] https://www.iqair.com/us/norway/oslo/oslo https://www.iqair.com/us/norway/oslo/oslo
alex_duf 7mo ago
This claim keeps circulating around and around and is not "EVs are producing more pollution", it's "if EVs are going at motorway speed, and if we only look at the pollution generated by the tires, then indeed they produce a little more". But that's completely ignoring tailpipe emission, and the fact that in an urban setting it's still vastly more advantageous to drive an EV. See https://doi.org/10.1016/j.trd.2025.104622 https://doi.org/10.1016/j.trd.2025.104622

RataNova 7mo ago

It's not just a "rich city" effect. That's kind of the key point in the whole EV debate... once it's mainstream and infrastructure is there, it stops being a luxury signal and just becomes… normal urban life, with some pretty noticeable side benefits

Vinnl 7mo ago

AFAIK, beyond a certain speed (~25km/h?), EVs make just as much noise as ICEs, since the noise is then mainly generated by the tyres hitting the road. So I'm somewhat sceptical about this claim. Dutch city centres can be really crowded and yet actually quiet, because there are practically no cars. It's probably not Shenzen-level crowded, but I'd bet that the number of people that are being transported at busy locations isn't too far behind. (As popular slogan is "cities aren't noisy, cars are noisy".)

Dumblydorr 7mo ago
Source? That sounds dubious. Here in USA you hear blazing engines constantly, I’m skeptical a rubber tire is louder than that
- Vinnl 7mo ago
  The source is "I heard that somewhere", hence "AFAIK". It kinda matches my experience at least when I get closer to a highway, the noise I hear doesn't sound like engine noise anymore.
  - Mawr 7mo ago
    Yeah, but you probably don't walk along a highway every day to get your groceries, do you. The closer the traffic gets to where people live, the lower the speed limit, and the more relevant the loudness of an engine. Another factor is that an EV has a noise ceiling, whereas an ICE can get arbitrarily loud — think motorcycles, buses, trucks. ICEs also use all of their noise range all the time — revving, accelerating. Sudden harsh noise changes like that are much more noticeable and annoying than the sound of a theoretical steady-state ICE engine.
    - Vinnl 7mo ago
      Unfortunately the steady background noise of cars I do hear around my house (and thus where I get groceries) mostly comes from the highway. But you're right, in the city centre it's partially this quiet because it's about the farthest you can get from the highway.