RACHEL MARTIN, HOST:
One thing you can count on this time of year - bad traffic. Whether it's shopping trips or holiday travel, the roads are packed. That means even a small disruption, like an accident or some roadwork, can plunge major parts of a city into gridlock. Some cities, though, are able to handle disruptions better than others. As NPR's Christopher Joyce reports, a physicist has figured out which ones.
CHRISTOPHER JOYCE, BYLINE: Cities with miserable traffic have inefficient road networks. There are more cars than they can deal with - places like Washington, D.C., Houston or Los Angeles. Take Los Angeles - normally traffic hell - you don't even have to go there to know. Movie people live there, and they like to show how bad it is, as in the film "Falling Down."
(SOUNDBITE OF FILM, "FALLING DOWN")
UNIDENTIFIED ACTOR: (As character) Hey, you cut me off.
(SOUNDBITE OF CAR HORNS HONKING)
UNIDENTIFIED ACTOR: (As character) What's a matter with you?
JOYCE: But LA, it turns out, does have something going for it, something called transportation resilience. That is, when a disruption happens somewhere, there are lots of alternative ways to travel. Igor Linkov, a physicist with the Army Corps of Engineers, found that local disruptions don't choke up big parts of LA. San Francisco, on the other hand, is not resilient.
IGOR LINKOV: In San Francisco, you have bridges - you have water. So if something happens in San Francisco, you are stuck, while in Los Angeles, people will find smaller routes around.
JOYCE: After Linkov studied 40 cities, he found that traffic resilience is independent of how bad normal traffic is. Philadelphia, for example, is normally pretty bad. But the city handles disruptions well. Jacksonville, Fla., and Providence, R.I., don't normally have such bad traffic. But a little disruption causes a lot of gridlock. The new research appears in the journal Science Advances. One thing that surprised Linkov was New York City. Given the density of the city, he expected that even small disruptions would jam things up.
LINKOV: But in reality, we don't see that much because of public transportation.
JOYCE: People just take the subway, or they walk. Linkov says public transportation is one way to make a city more resilient. Or you can do what he's doing after he moved to the Boston area.
LINKOV: I'm actually - I am trying to find multiple back roads. In Boston, there are many back roads.
JOYCE: Linkov's research measures resilience in 40 cities. It does not include back roads, so you'll have to find those yourself.
Christopher Joyce, NPR News. Transcript provided by NPR, Copyright NPR.