In his latest blurb, he points to evidence that it's the number of bike lanes, and not so much about the weather:
Indeed, depending on how you judge what makes a city best for cycling, it’s often the colder ones that win out: Frozen Minneapolis is one of the best biking cities, thanks to well-built infrastructure and a bike share system. Rainy Portland continues to have the largest percentage of its population commuting by bike, a fact that should continue to shame city managers whose polities stay pleasant all year round.I've got to agree with this block quote from GOOD.IS; I much prefer biking in colder weather than in hot. Not only do you get to work without all the sweat (or less sweaty at least), but you also build up a good amount of heat. I have even I had to stop to take off my jacket in -10C degree (or colder) weather because I was sweating (and I didn't want the sweat to freeze). However, once that jacket was off, the low temperatures helped keep me cool and sweat-free for the rest of the trip.
Oh, yeah: also the bike lanes that exist in Ann Arbor (at least along the section of city that I cycle along) really make the trip a lot less daunting than on similarly busy roads that don't have them. I shudder when I think about people who actually cycle on Washtenaw Ave...
And Sullivan draws the good link between needing bike lanes to increase cycling in a city with the future need for more bike lanes:
By 2050, we’re going to see 3-4 times more global passenger mobility and we’re going to have to accommodate the transport needs of more than 9 billion citizens. Mass urbanization presents an amazing opportunity to get more people cycling: 30% of urban trips are less than 3km (1.86 miles) and more than half of all trips are less than 5km (3.1 miles).Personally, I'd not like to see all that population growth get into cars, try to find parking in the same downtown areas, and try to all get going on the roads. It will need a major re-think about how we - as a society - approach transportation. Perhaps those of us living in the United States will come to understand that not everyone can rationally (nor should anyone really feel obligated to) drive several tens of miles in one direction to get to work. Maybe - as we get evermore crowded - we will come to recognize that this individual car ownership thing isn't really all that it's cracked up to be ... and that it's okay.
Until that time, though, I'll be saving money that would otherwise go to buying gas (~$1,000/year), car insurance (~$750/year), registration (~$100), maintenance (~$500/year) -- assuming that it's a 2007 Ford Focus (just pulling a car out of the air which happens to be the same as this car-ownership assessment) -- and parking (~$200/year). At those numbers, with the savings, I can buy a new fully-kitted-out bicycle ever year. (And that's assuming that I own the car, and I'm not also making interest payments on the sucker.) In contrast, over the last year, I normally spend $300-$400/year on maintaining my bike (this last year I also spent about $800 for a complete replace and rebuilt of my rear wheel, including a new internal hub).