The low was zero degrees Monday. It was 26 Tuesday, dipped to 23 Wednesday and was 16 degrees as the morning commute began Thursday.

Those frigid temperatures were recorded in Montreal, Oslo, Copenhagen and the District.

Other than bitter cold, these four cities had at least one other thing in common this week: a lot of people pedaling around on bicycles. Getting places on two wheels has become a year-round option in the District and its environs, much as in Montreal and many European cities.

“I don’t like the cold, but today when I got up and checked the weather, and they said it was 17, going up to a high of around 30, I figured that would be okay,” said Elizabeth Floyd, 41, who bundled up, put her purse in the basket attached to her handlebars and rode about three miles from her home in Ballston to her office in Rosslyn. “The first day of the polar vortex, I didn’t bike and had a miserable time trying to get a bus, the Metro, a Capital Bikeshare bike, a different bus, then two other buses. I should have just biked that day. It would have been easier.”

Floyd is among a growing number of people in the area who don’t own cars. A report this month by University of Michigan researcher Michael Sivak said Washington ranked second to only New York in the percentage of car-free households. At almost 38 percent, the number of carless in the Washington area had increased by 2.4 percent in five years.

A bicyclist crosses the Key Bridge on January 30. (Matt McClain/The Washington Post)

Floyd planned to stop by the gym and do a number of errands by bike before heading home to Ballston on Thursday evening.

“It will just be easier to do on the bike rather than figure out buses,” she said.

A researcher at McGill University in Quebec who studied winter cycling in three large cities concluded that “despite the fact that adverse weather is an important deterrent of cycling activity, a significant proportion of cyclists continue through the winter.”

“Ice” was Dave Dugard’s one-word answer when asked about any conditions in which he won’t ride his bike the 14 miles from his home in Annandale in Fairfax County to his office in Southwest Washington. “If it’s dry and cold, I’ll ride.”

Cold, he said, can be defeated.

“I usually wear three thin layers under my bike jacket,” Dugard said. “If it’s above freezing, usually I’ll wear shorts to ride, but when it gets this cold, I wear sweatpants underneath my shorts.”

Thursday on his mountain bike, he encountered what he fears most: “The trails have been horrific with ice. I about near killed myself this morning.”

Alex Pline is among the winter riders who have established a trend in recent years. Those riders begin or end their commute by bicycle and use public transit in between. He sets out from home in Annapolis on his 40-year-old brown Schwinn and then catches a bus into his job in Southwest.

“I love my morning rides to the bus stop, usually about 10 to 15 minutes, because it gets blood flowing to my muscles — I am always stiff in the morning. Getting old is not for the faint of heart,” Pline, 52, said. “I always wear long johns in this weather, even not riding the bike, because it makes being outside much more tolerable. I think that’s one of the reasons people don’t deal with cold weather very well. They do not wear weather-appropriate clothes, and driving really facilitates this, since you rarely have to be outside for more than a few seconds.”

Bikes provided by the popular Capital Bikeshare program have been used for 104,431 rides thus far this month, and survey data collected by the program last year found that 54 percent of Bikeshare members use it to access Metro lines, and 23 percent use it to access a bus.

“Bike riding is actually just an everyday thing for many people, and it could be for many more if the false perceptions [about riding in the cold] were not out there,” said Chris Eatough of Bikeshare’s Arlington County division. “Many are not affected by the weather. It’s part of their daily routine.”

Gillian Burgess, 34, returned in 2008 to the city where she had gone to college. The mother of two toddlers pedals 7.5 miles from Arlington to Capitol Hill every day.

“When I went to school here, I was in my 20s and I think I only knew one person who rode, also in her 20s,” Burgess said. “Now you see people of all ages riding — people in their 30s, 40s and 50s. There’s so much more riding, and the infrastructure is so much better.”

In addition to Capital Bikeshare, the city has added more than 50 miles of bike lanes and more than 1,000 bike racks.

That encourages riding, even in the cold, Floyd said.

“There’s always more people when the weather’s warm, but interestingly, there has not been a lack of people on bikes,” she said. “And there have been several mornings where I’m getting off the bus and I see people going by me on their bikes and then I feel guilty because I didn’t bike.”

“It’s all relative,” said Michael Berry, who has commuted 36 miles each way by bike from Annapolis to downtown D.C. almost every day for several winters. “There are avid bike commuters in Alaska and elsewhere who routinely brave much colder temperatures. They would love to have our weather. That puts it in perspective for me.”

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