Photo by Mike Koozmin.

We’re a party town. We’re a highway town. And now we’re also one with a growing air quality problem, especially in the Mission District. The chief cause of the newfound air quality woes is density.

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Courtney Quirin is a trained wildlife ecologist turned environmental journalist with a knack for photography and visual storytelling. Though her interests span many topics and disciplines, she's particularly keen on capturing multimedia stories pertaining to the global wildlife trade, human-wildlife relationships, food security, international development and the effects of global markets on local environments and cultural fabric. Courtney completed a MSc in Wildlife Management at the University of Otago, New Zealand, where she not only learned how to catch and tag fur seals (among many things) but also traveled to the highlands of Ethiopia to identify the nature and extent of farmer-primate conflict and its linkages to changes in political regime, land tenure, food security, and perceptions of risk. From New Zealand Courtney landed at The Ohio State University to investigate urban coyotes for her PhD, but just shy of 2 years deep into the degree, she realized that her true passions lie within investigative journalism. Since moving into the world of journalism, Courtney has been a contributor to Bay Nature Magazine, a ghostwriter for WildAid, and the science writer for While at Berkeley's J-School Courtney will focus on international environmental reporting through the lens of documentary filmmaking and TV.

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  1. The quid pro quo for the Mission having the best weather is that it also having the worst air quality. It’s not just the freeways. Low-lying hotter areas routinely have the worst pollution.

    The higher ground is cleaner. you get more wind blowing away the muck.

    And, the further west you go in the city, the cleaner the air, as the prevailing winds are from the west.

    In fact, Oakland has worse air quality again because, in addition to their freeways, industry and docks, they get a lot of our emissions blown across the bay.

    If you want clean air, live on a hill on the western side of the city. There’s a reason that historically the rich always lived on the hills and the poor lived on the flatlands. Pretty much true for every city.

    1. The heights are clean because it’s hard to push a shopping cart uphill. Bonus: all the garbage-juice (real and metaphorical) generated up there flows downhill.

    2. The report is here (PDF).

      An analysis of the Mission versus the Outer Mission starts on page 116. The Outer Mission is to the east of the Mission– and indeed, a freeway– and so things should be worse there per the hypothesis that the respiratory health issues stem primarily from crud blowing east with the prevailing winds. However, that’s not the case.

      Not that you’re coming from left field with any of this- but while you’re on point about Oakland, coming in too close means you end up trying to apply regional-scale rules of thumb about meteorology to microclimate-scale details of neighborhoods. Down at this level, annoying details about how many people are where and the physical layout become important. That’s why the folks at MIT drilled down to peering at block layouts– page 119– and concluded that the real difference between the two neighborhoods was density of development.

      This has obvious implications for questions of whether additional development in the City is a good idea. Anti-development folk are diverse, so it’s unwise to try to say something alleged to account for all of them– but the sane ones with some knowledge of urban planning, at least, are trying to keep the City from going the way of Los Angeles.

      1. Except that LA is actually less densely populated than San Francisco. In fact, it’s not even close.

        The most populated town in California is reputedly Fresno, which is neither particularly large nor densely populated.

        What this really tells us is that jumping to generalizations about air quality can be dangerous. Which is why I restricted myself to the two things that appear to hold up universally – it’s better to be on higher ground, and in cooler, windier locations.

        Note also that there are many things we can do to improve air quality even while we build up density.

        1. Everything else is all good points, but I’m not sure what you mean about Fresno If populated was a typo for “polluted”, these days the most polluted city in California is Bakersfield— which, indeed, is neither particularly populous nor particularly densely populated, and so supports your point. (CNN attributes its problems to “hemmed in on three sides by mountains” and “a major oil producing region, which introduces diesel soot, from well pumps, and chemical fumes into the air”– so it’s an example of a city where the pollution is from industrial sources rather than lots of people. Merced is #2, and Fresno is #3, with CNN attributing Fresno’s problems to “The Fresno metro area’s population sharply increased 16% between 2000 and 2010, spurring the once compact city to sprawl outwards. Now, residents drive much further distances to get to work, leaving a trail of exhaust and emissions.”)

          The problem with Los Angeles isn’t its density as such; it’s its slapdash approach to city planning. Between already devoting the bulk of its actual land area to transportation infrastructure and having more land nearby to work with, they can afford a policy of sloppy city planning that lets developers do more-or-less what they want. San Francisco doesn’t have those luxuries; the incredibly careful process and strong restrictions on density are necessary to keep from overwhelming an already stressed infrastructure.

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