Good luck finding a sunny day because Pittsburgh enjoys the fewest hours of annual sunlight of any major city, and continues to have air quality as bad as any other US city, being in the top ten worst according to the Lung Association.

Most people in California don't realize that the air quality in the San Francisco Bay Area is actually worse than in Pittsburgh [1].

Moreover, after growing up in Pittsburgh and living in Seattle, I can tell you that Seattle definitely has less sunlight (it's not even close) than Pittsburgh. So much less that my doctor had to prescribe my Vitamin D to address a deficiency I had when I moved there (after living in Pittsburgh my whole life, no problems).

[1] "California is home to eight of the 10 cities in America where air pollution is worst" https://qz.com/963089/california-is-home-to-eight-of-the-10-...

Most people don't realize that because it's not true. The air quality of the combined statistical area of San Francisco is worse than that of the CSA containing Pittsburgh, but pollution in the expansive San Francisco-Oakland-San Jose CSA is centered elsewhere, whereas Pittsburgh is the pollution epicenter of its CSA. This is due chiefly to its geography, not some kind of moral failing. San Francisco has very favorable geography for air quality.

As for your linked article, that seems irrelevant. Nobody thinks Hanford, CA is an upcoming tech hub.

I'm not sure Pittsburgh is much sunnier

Rank City Annual % sunshine 164 PITTSBURGH, PA 45% 165 SEATTLE C.O., WA 43%

I don't feel like there's any major lack of sunlight and I've lived in Pittsburgh for years. Source?

Seattle is shown to be even worse in the winter months than Pittsburgh on that chart.

Seattle is at a higher latitude.

Winter often has very long periods of ZERO sun, literally not being able to point at where the sun is. My GF called it "gloomy doomy". During the winter I would actually forget what a sunny day looked like.

Often remarked that we had less rain than Portland, but also less sunny days.

What causes the poor air quality? There are no obvious pollution sources other than cars.

There are still major steel works in the area, some of which are operating with grandfathered emissions limits. Also Pittsburgh receives the wind-blown emissions of practically every coal-fired power plant in the nation.