Where does air pollution come from?

1 day ago (ourworldindata.org)

One of the most striking aspects of air pollution is how invisible yet pervasive its effects are. Unlike more immediate environmental disasters, air pollution slowly chips away at public health, reducing life expectancy and quality of life, often without dramatic headlines. The comparison to starvation as a "frailty multiplier" is an interesting one; pollution doesn’t always kill directly but makes people more susceptible to fatal conditions.

Regarding the reduction in SO₂ emissions from shipping fuel, I’d love to see more discussion on how international regulatory pressure (e.g., IMO 2020) managed to enforce compliance in an industry notorious for cost-cutting. Was it simply a case of the alternatives being feasible enough, or did global coordination and monitoring play a stronger role than usual?

  • The other striking aspect for me is how, as has often been the case, those most affected are the poorest.

    Levels of asthma in London are highest among kids in the vacinity of the docks where cruise and container ships and moor. They sit there running their engines for power, churning out SO2 and other pollutants. These areas are some of the poorest in London.

    The same was the case in industrial cities during the industrial revolution. The poor factory workers lived close to the factories, and their kids grew up breathing the smoke. The wealthy owners moved to the outer suburbs (often upwind) where the air was clear.

    There was a bit of an uproar a few years back about how many premiership football players were using asthma medication, a higher rate than the general population. The implication being that they were using them as performance enhacning drugs. But if you take into account that they disproportionately come from poor inner-city areas (not all, but many more), the proportion with asthma looks much more in line with the background rate.

    Urban air pollution is insidious. Unlike the dreadful smogs of previous generations that lead to things like the Clean Air Act and the banning of open fires in urban areas, today's is invisible, and so doesn't create the same political problems. In fact if you try to do anything about inner city pollution you can pretty much guarentee an angry pushback.

    • > Levels of asthma in London are highest among kids in the vicinity of the docks

      Someone else pointed out that there's very little shipping in central London now. It's all cars and buses causing this pollution.

      > In fact if you try to do anything about inner city pollution you can pretty much guarantee an angry pushback.

      See how bonkers people got over the ULEZ: https://www.bbc.co.uk/news/business-66268073

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    • > There was a bit of an uproar a few years back about how many premiership football players were using asthma medication, a higher rate than the general population. The implication being that they were using them as performance enhacning drugs. But if you take into account that they disproportionately come from poor inner-city areas (not all, but many more), the proportion with asthma looks much more in line with the background rate.

      That part can also be explained because asthma drug is used as masking agent when taking steroids and other PEDS, which is quite common at this level.

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    • > There was a bit of an uproar a few years back about how many premiership football players were using asthma medication, a higher rate than the general population. The implication being that they were using them as performance enhacning drugs. But if you take into account that they disproportionately come from poor inner-city areas (not all, but many more), the proportion with asthma looks much more in line with the background rate.

      You can get asthma just from breathing really hard too much. Especially in cold climate. Due to this it is really common with endurance athletes.

      For example https://barcainnovationhub.fcbarcelona.com/blog/asthma-in-el...

    • > Levels of asthma in London are highest among kids in the vacinity of the docks where cruise and container ships and moor.

      Wait, what? There are no container docks in London. The nearest container port serving London is Tilbury, near the coast. Occasionally a single cruise ship moors in the Pool of London against the HMS Belfast, but that's happening only one this month, for 12 hours on April 7, according to the Tower Bridge lift schedule: https://www.towerbridge.org.uk/lift-times

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    • > those most affected are the poorest

      Please pardon my pedantry but this is by definition what poor is : having less means to escape material woes. Rich people are the ones that can elect to live in healthy areas.

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  • I think part of the IMO2020 compliance is that fines have actually been applied for ships that have broken previous similar regulations.

    https://www.theguardian.com/world/2018/nov/26/cruise-ship-ca...

    It turns out that the previous 2015 regulations around the USA and Canada were also largely followed, even offshore - this is despite there being little monitoring capability away from ports (I worked on this study).

    https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201...

    I am not an economist, but I suspect part of the compliance is a case of 'as long as everyone is forced to do it', we are okay with it as everyone can/has to raise prices.

  • Also, the industry had a few years of lead time to prep, which probably helped avoid a full-blown logistical panic

I thought that this article will address an elephant in the room but either it missed it or I missed it.

My problem with pollution is that… you need to measure it, and those who pollute don’t do it consciously. Anecdotally I often drive through a small town. You can smell pollution, a plastic smell. In winter you can see column of smoke coming out of chimney. Sometimes it’s milky white, sometimes it thick black. There are many like that. I asked shop keeper is it happening often, she confirmed and said that no one is interested in doing otherwise, installing sensors was directly opposed by town council.

The town is not on a pollution map. Nearby cities are with medium-high pollution but that particular region is supposedly clean as reported by a single sensor positioned somewhere on a hill.

It’s not like there is one town like that in the world. There are nations that pollute heavily and don’t care and don’t meter the impact. I would be curious if all the effort, regulations etc. are worth it when applied to average Joe versus huge polluters.

  • > I asked shop keeper is it happening often, she confirmed and said that no one is interested in doing otherwise, installing sensors was directly opposed by town council.

    One way to address this sort of localism (where there's a significant risk that the owners of the factory are slipping the town councillors the odd brown envelope) is a national regulator. The Irish EPA, which was created to take this sort of thing out of the hands of the local authorities, has been very effective in reducing nuisance pollution; the local authorities used to be mostly pretty useless. Any industrial facility of this sort would be required to self-monitor, and would be subject to inspection; it would have to respond to any complaints, and if the regulator wasn't satisfied it could demand improvements, on pain of withdrawing its operating license.

    • > (where there's a significant risk that the owners of the factory are slipping the town councillors the odd brown envelope)

      This is in no way necessary, and is almost never what's going on. All that is needed is the factory owner quietly telling the town councillors that if they are forced to clean up their emissions, they will not be able to compete with foreign competitors who don't have to do the same, and will be forced to close. Then the town council takes a quick look at just how much of the wages and tax revenues of the town come, directly or indirectly, from the factory, and make sure nothing threatens it.

      Now that tariffs are the issue du jour, I'd like to propose that any environmental regulations or labor laws should always be combined with an automatic tariff on any competing products produced in countries that do no have such laws. To not have that means that you are not removing the problem, you are just moving it to somewhere without such laws.

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  • That small town might get even more pollution from all the cars driving through it, though. It's counter-intuitive, but columns of smoke from chimneys might often just be water, or be too high to really affect locally (but globally it matters, of course) compared to cars driving and flinging dust where people breathe.

Interesting article. I always assumed that a large part of the "soot" air pollution in cities came from car tyres as well, since their compounds are one of the main sources for the dust that deposits in apartments.

  • Particles from tires and brakes account for a significant chunk of pollution. I'm in the middle of reading Dust: The Modern World in a Trillion Particles which goes into those details.

    https://www.amazon.com/Dust-Story-Modern-Trillion-Particles/...

    • Cars become worse the more you approach colder climates. Every fall and spring there are multiple weeks during which asphalt roads are dry from sunlight and warmth, which leads to studded tyres chewing through asphalt. Not only that, the sand we spread on roads to help people stay on their feet also helps in creating massive amounts of dust. It's so difficult to time the change from summer tyres to winter tyres.

      It's quite possible to survive with friction tyres with the help of good traction control (especially from an EV) but there are vast areas of the country that do not get roads plowed in a timely manner, so it's "safer" to go with studs.

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For those who are worried about indoor air pollution like me, I found out thanks to this [dynomight post](https://dynomight.net/ikea-purifier/) that having an efficient air purifier is a low bar and is actually quite accessible to poor people like me !

  • I ended up purchasing a Lasko Air Flex[1]. It fits standard HVAC filters. It doubles as a white noise machine for me, it is quite loud. This review[2] indicates it works well but a bit power hungry, and it definitely gathered a visible amount of dust over a 1 year period.

    [1] https://lasko.com/products/lasko-air-flex-2-in-1-20-inch-box...

    [2] https://youtu.be/daayXtlpg_o

    • Standard filters is interesting but it looks that the Ikea one has many advantages: it's smaller, discreet, less power-hungry, has textile pre-filter so that you filter will work longer, can accommodate activated charcoal filter and is not loud on 1

  • Air there any air filtration systems that use water (maybe by bubbling air through water or a fine mist) to remove particulates? Like a canister vacuum cleaner, I'd love to be able to see the dirt/dust/particulates/gunk that is being removed from the air.

    • It's a pretty common method in industry (a wet scrubber) but I don't know of any indoor-scale, self-contained units - it sounds like a recipe for mould because a misting one would basically be a humidifier too, and they are hard to maintain because bacteria like legionella can grow in the water and then you're dispersing it inside your house!

It's wild how many pollutants trace back to the same root cause: burning stuff. Fossil fuels, biomass, agriculture byproducts - it’s all combustion and decomposition in different forms.

In 2019, ambient air pollution claimed the lives of young children at alarming rates in several countries. Here's the top 10 list of countries with the highest number of deaths per 100,000 children under 5 due to ambient air pollution: Nigeria – 18.95 Chad – 18.10 Sierra Leone – 12.02 Mali – 10.56 Guinea – 9.90 Niger – 9.64 Cote d'Ivoire - 9.04 Central African Republic - 8.79 Cameroon - 8.69 Burkina Faso - 8.68

These numbers highlight how air pollution isn't just an urban problem — it's a public health crisis in low-income countries where children are the most vulnerable.

Source: Baselight analysis using data from Our World in Data, originally supplied by the World Health Organization (WHO). https://baselight.app/u/pjsousa/query/top-10-countries-with-...

  • Not that this isn’t terrible, but those numbers look really low. Surely malnutrition and violence must be a hundred times more likely to kill them?

    Not trying to say we shouldn’t consider this, but it seems like there’s bigger fish to fry first (assuming we can’t fry them all at the same time).

    • >Not that this isn’t terrible, but those numbers look really low. Surely malnutrition and violence must be a hundred times more likely to kill them?

      They don't seem low at all to me. And a quick search suggests that malnutrition probably causes fewer deaths [1] (note that it's counted for all people here, not just under 5).

      And in places like India and SEA, where malnutrition and violence are less of a problem, air pollution stands out even more.

      [1] https://ourworldindata.org/grapher/malnutrition-death-rates

    • Take Nigeria - capital is cca 6 million. That means, that every year around 1150 children die from just air pollution alone, every year.

      That is properly fucked up for children under 5. They start with absolutely clean lungs and the damage compounds so much they die from it. Think about all the other age groups that have some other horrific numbers.

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What still baffles me is the reduction in SO2 emissions due to regulations on shipping fuel.

How did the shipping industry accept / manage / afford to switch fuels (presumably, to more expensive ones) in order to follow the regulation ; as opposed to delay / deny / deflect, or plain old lobbying the hell against the changes ?

Are we in a "Montreal protocol" situation, where the alternative was existing and acceptable and in the same price range ?

Or did one actor implement coercion differently ? Was a standard change made, that enabled drop-in replacement ?

(If we were living under Discworld-like physics where narrativium existed, I would understand _why_ the change happened : it's making climate change worst, so of course there is all the power of narrative irony.

Are we in a world governed by narrative irony ? That would explain so many things...)

  • SO2 was the main driver behind the forest dieback. I'd estimate that the global investments in forrest property (mostly by old money) dwarfs the total cost for the switch to sulfur free fuel.

    It is remarkable how fast the wheels of progress turn when old money faces the prospect of their assets being washed away.

  • Are we at the point where corporate adherence to laws is considered shocking?

    • To be honest: yes, at this point, and with an industry of this scale, it's a bit shocking to me.

      I don't know the main actors here, but I imagine the leverage of shipping companies on western countries is incredible ? ("oh, you think our boats are too polluting ? sure, let's see how you bring "about everything that's sold in about all your shops but that is manufactured half a world away" without our boats.")

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    • Yes, e.g. compare that to agriculture where emissions are still increasing exponentially. The political power the farmers have is amazing, apart from the fact that they managed to get exempt from emissions penalties in many countries, they also continue to be able to push increased meat and dairy consumption which does not only increase pollution but has many other serious environmental and health impacts.

Something I haven't quite figured out is why my perceptions of cities' air pollution differ dramatically from their readings as reported by air quality sites.

I suspect readings are quite dependent on the specific location of the reading device. E.g. if the air quality monitor is located in a claustrophobic city street with lots of motorcycle traffic (e.g. Nha Trang), air pollution might be through the roof, but 100m away on the beach it might be clean(ish) air. Similar for 'leafy' cities (e.g. Singapore), where 100m can make a huge difference in air quality e.g. near a park vs beside a busy road.

Curious to know if the science backs up my suspicion that ostensibly 'polluted' cities sometimes have unpolluted alcoves (and 'clean' cities have spaces with bad air), so your micro environment really matters (more than the 'average' reading for that city, anyway).

  • Percentage wise absolutely, said beach can have 99% less pollution.

    but in absolute terms, pollution is so high in that street that even 1% of said beach pollution (which is already 1% of street) is already out of bounds of limits considered safe. Blue "haze" is pollution, not fog (water vapor).

    Look, people do not understand scale, one motorcycle/lawnmower can have emissions of 300 cars equipped with catalytic converter. So in your street, there is 100 motorcycles which produce as much pollution as 30 000 cars in new york. this is not hyperbole to make a point. These ratios are physical reality.

    electric cars have no emissions (except dust from tires which is same as fossil car). so why even use fossil transport is beyond me. also you can charge motorcycle from solar panel on your roof.

    buses, vans, boats can have solar panels on their own roof to expand range of said vehicle. in malay or indonesia there is sun shining almost same throughout year. in europe /usa we have huge difference between summer and winter insolation and sun angle.

    • The faster acceleration and tendency to be heavier do usually make EVs worse for tire pollution, which if nothing else is a really good reason not to pinch the accelerator if you own one.

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    • electric cars do not have emissions, true, but generating the electricity to power them does generate emmissions.

      Also, electric cars are heavier. This means not only higher tire pollution, but also they are inherently less fuel efficient.

      electric bikes, on the other hand,

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  • I'd guess that a big factor is differences in the type and particle size of the pollutant.

    Large particles are probably a lot more localized, but pm2.5 are going to diffuse fairly evenly over a large area.

    I'd guess larger particles and certain chemicals are more odoriferous as well.

Really wish they showed deaths per capita instead of raw deaths for all their data sources. It would be better for doing country by country comparisons

It is easy to be 'green' and 'net-zero' when all you do is exporting your polluting production elsewhere and importing the goods while leaving the dirt on the manufacturer's books, and trade away your own pollution with nifty 'carbon credit' scams.

Top marks for never curbing your consumption while claiming the superior virtue position.

Extra credits for wagging a damning finger at those 'polluters' that actually make and ship your stuff.

  • The top ten countries by air pollution listed in another comment hardly produce anything the developed world uses, they mostly export natural resources.

What's scary is that all significant sources of pollution are going down, except the ones related to agriculture (ammonia and methane) which are showing no signs of slowing down. I feel like you can bend the heavy industry because it's just "a few" people to convince, but you can't change 7B people's eating habits :/

  • Curated meat might eventually make a dent. Hopefully.

    • Lab grown meat seems to be comparable to classic meat in terms of environmental impact so at the moment it seems to be better purely in moral terms.

      I wish we'd bite the bullet and go all in on vegetarian and vegan foods but we need to invest a ton in them to make them more palatable and easily accessible, including to poor people.

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It's interesting to see the number of deaths caused by pollution. But everyone will die of something. Could it be that many of those people whose death was caused by pollution may have been frail and close to death anyway? I wonder if it would be more useful to talk about quality-life-years (QUALYs) lost as a result of pollution. Probably much harder to get that data though.

  • One cohort susceptible is asthmatics.

    Most asthmatics can live a long, healthy life - certainly not die at the age of 9 https://apnews.com/article/asthma-europe-london-air-pollutio...

    I, along with other asthmatics, did notice a marked improvement in symptoms during the Covid 19 lockdowns as there was less traffic on the roads - https://pmc.ncbi.nlm.nih.gov/articles/PMC8011425/

    This is the problem with "Well, these people are frail, and you have to die of something" assertions. See also, Covid 19 and "most people who died weren't healthy, they had other conditions!".

    • There's something to be said about quality of life, too. Just because something doesn't outright kill you (sooner) doesn't mean it's fine to live with it.

      I'm not asthmatic, but last summer I had an eye-opening moment about pollution. I live in a very dense city, and I regularly go for short runs in a local park. Last summer I spent a few weeks at my parents' house, who live in the suburbs of the same city, only farther away, in a small town surrounded by fields and forests.

      When I went running in the forest, I couldn't believe how easier it felt to breathe and how all-round easier my session felt, event though I ran faster and longer. I don't usually run so fast that I'm out of breath, but that particular time I felt a marked difference in how easy breathing felt. It was as if I needed to breathe in "less air" to get the oxygen I needed.

      I had already felt a similar thing after the first covid lockdowns coming back to the city. I had sensation of something "rough" in my throat and had short bouts of coughing. This was a few days after the lockdowns lifted, and people were still weary of public transit so everyone on their dog were sitting in gridlocked cars on the roads.

      I think it's the same thing with ambient noise. After some point, we just don't notice it any longer, but it does take its toll in stress and all-round irritability.

  • Linked from the article this seems interesting: https://ourworldindata.org/data-review-air-pollution-deaths

    But from my understanding most deaths attributed to pollution, specially indoors, relate to fireplaces, cooking, oil lighting or other "I'm making smoke indoors" activities which will cause lung issues later on. Even having candles on all the time isn't good for you.

    The rest as far as I understand is all estimated by putting a finger in the air and subdividing lung cancer deaths into what they feel like the causes were.

  • Pollutions impacts people across all age groups, including children and otherwise healthy adults. Many pollution deaths aren't inevitable near-term deaths.

    Health effects include:

    - Respiratory diseases developing in otherwise healthy people

    - Cardiovascular damage at an early age affecting long-term health

    - Developmental impacts on children with lifelong consequences

    - Cancer and other conditions with substantial life-shortening effects

  • Found this in an article linked to by this one:

       Exposure to air pollutants increases our risk of developing a range of diseases. These diseases fall into three major categories: cardiovascular diseases, respiratory diseases, and cancers.
    
        It makes sense to think of these estimates as ‘avoidable deaths’ – they are the number of deaths that would be avoided if air pollution was reduced to levels that would not increase the risk of developing these lethal diseases.

  • > Could it be that many of those people whose death was caused by pollution may have been frail and close to death anyway?

    What point are you trying to make? I mean, you don't seem to dispute that pollution can and does kill people.

    • Yeah, but there's a big difference between dying a few months earlier when you'd already be bedridden with your mind mostly gone and dying 50 years early.

      Which is why QALYs are such a good metric.

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  • You're right, "everyone dies of something" is technically true, but the key issue with pollution isn’t just that it shortens life, it's how it does it. Chronic exposure doesn’t just tip over the already frail, it increases the burden of disease across the board

  • Try going to a heavy polluted city, something like Delhi in the Winter. You would honestly have no doubt about how bad it is for you health. Because you will feel it within the first 24 hours.

  • everyone will die of something, reduce risks and everyone will die after more time, or better.

  • I think pollution is better thought of like starvation, as something that makes you frailer so that you end up dying over something that a healthier person would have survived. Pretty much the opposite of the perspective you take.

    You don't see a lot of people arguing that starvation doesn't mean much because the deaths of starving people are more directly caused by disease or injury.

  • As you said, everyone will die of something and those who die are close to death. Therefore you can now justify abandoning any treatment that increases lifespans. The new baseline lifespan is shorter, therefore everyone is closer to death, let's abandon the next treatment.

  • >It's interesting to see the number of deaths caused by pollution. But everyone will die of something.

    People can die because they don't have access to energy or agricultural products.

    I wonder what would be the word population now had we not used fire, coal oil, haf we not grew rice and cereals, had we not raised cows and sheep.

The charts for black carbon seem to have the labels for "Buildings" and "Energy" switched.

I wish articles like this would give some attention to how much we've already improved. We used to drive leaded gasoline, for example. The amount of damage that caused puts NOx to shame.

  • It’s true that we’ve stopped some especially bad things - the anti-CFC campaign should get more attention – but part of the problem is that we haven’t improved in aggregate. If Californians drive cars which get 50+ mpg with low emissions, but a hundred million people in India start driving new cars with less strict emissions controls, the planet is in aggregate worse off. Something over half of the CO2 in the atmosphere was emitted after 1990, which is a general proxy for the rest of the world industrializing.

  • And smoking! And, further back, banning of coal burning in cities, which led to lethal fogs in 1950s London.

  • As mankind? Think how many cars were there in South America, Africa or Asia 50-70 years ago. Its what now, 100x more?

    Even in Europe its at least 10x but probably more compared to my childhood where I lived (east & west). My parents used to play as kids on the roads next to their places, those few cars per hour were slow and easy to spot and hear. Now its a car every few seconds at least.

    We also found plenty more way to pollute and more types of materials to burn. Also all is now permeated with micro and nano plastics.

Perhaps the most surprising sources of particular matter is... sea spray. As water crashes around, stuff in the water (e.g. salt) often ends up suspended in the air. This apparently contributes a non-negligible percentage of PM2.5 matter in coastal areas, though exact percentages are hard to come by.

  • While I’m quite concerned about particulates generally (I use a few HEPA air purifiers around the house etc.), with this kind of thing it does feel like that kind of matter can’t be as bad for you as other types of PM2.5. I haven’t yet seen any research quantifying it (most studies just look at all PM2.5 as a single category) but surely there must be a difference about how bad different types of particulates are depending on what they’re made of - like those from combustion, tyre wear etc. it would seem are very obviously going to be toxic, but I also measure raised PM2.5 from cooking with my electric oven or induction stove (but not burning the food), surely that can’t be quite as bad? And sea spray you would think would be even less harmful…

    • Most definitely different types of particles cause different levels of harm. (Extreme example: asbestos.) However, we don't really have good data to quantify this. It intuitive from evolutionary perspective that "natural" sources would be less harmful since we've been breathing sea spray and dust for millions of years. Yet, smoke from wood fires is clearly still extremely harmful. So... my instinct is that the harm is probably less, but I find it very hard to be confident that any particular source is totally safe.

Does anyone have advice for how to balance air purification with CO2 levels? My apartment will sit at around 1200 PPM if the windows are closed, but if they are open I would think running a purifier does nothing.

Looking at how much pollution is from energy, solar does seem to be the best thing that can happen in current timeline to humanity. Global warming AND pollution gone in a single stroke.

  • Solar panel price have never been so low. It's only a matter of time before 'the invisible hand of economy' makes people buying them en masse.

    • It's already doing that but progress is hindered by installers that overcharge due to high demand and due to utility companies trying to cushion their blow of upgrading their infrastructure and doing all sorts of shenanigans.

So is domestic aviation negligible in every way? Is non-domestic aviation part of the transport category? Not clear to me.

  • Those get lumped under transportation, which is non negligible. It's not broken down any further

I fondly remember the police driving through my small town, telling everyone to stay at home because the tire yard is burning again.

Does anyone recognize the plotting library they're using? Those interactive charts are really nice.

After experiencing the COVID-19 pandemic, I have developed the habit of wearing a mask.

  • Yeah... The thing is surgical or cloth masks don’t do much against PM2.5. For actual pollution, you’d need a well-fitted N95 — anything less is mostly placebo with ear loops.

The deaths breakdown by region is interesting:

Africa: 1.8M

South America: 149k

North America: 179k

Australia: 4k

Europe: 434k

Asia: 6.3M

I guess to keep it positive, I'd say "Great job, Australia"!

  • Asia has about 4.8B population, Australia has 26M. On a per capita basis Australia has about 1x% more deaths

    • > Asia has about 4.8B population, Australia has 26M. On a per capita basis Australia has about 1x% more deaths

      6.3e6/4.8e9 = 0.00131

      4e3/26e6 = 0.00015

      About 9x as bad?

      Not sure about 1x%, was that 1% worse? I am sorry I might have misunderstood that.

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    • My thoughts exactly. Africa and Asia see the highest numbers but this is proportional to the population count. Plus, countries in these regions have less advanced healthcare than in countries like Australia, but the latter still has a higher death rate. Quite mysterious.

    • On a per capita basis, Australia has world class epidemiology, medical record keeping, and "no sparrow falls" cause of death certification . . .

      This might be a case of a shortfall in record keeping and open reporting.

  • > I guess to keep it positive, I'd say "Great job, Australia"!

    Would be interesting to see how much of that is due to proactive regulation

    • I would guess better regulation, better medicine, less reliance of burning coal