Questioning “the barbecue effect” as city residents travel more each year

One European researcher wanted to explain why city residents travel more kilometers each year than suburbanites:

Why do city dwellers so urgently need to get away? Statistics show that they cover a large number of kilometers in their free time, often travelling much longer distances than suburban residents. What are they after? And what is the energy cost? Research carried out at EPFL shows that, rather than making up for a supposed lack of green space, city dwellers also seek the density of other cities or the company of friends and family. And despite the distances they cover, their carbon footprint is lower than that of suburban residents. And for good reason: they use public transports more and cars less.

These conclusions contradict a hypothesis commonly advanced to explain the large number of kilometers covered by city dwellers: to enjoy nature and some quiet time, things not available at home. Under this same hypothesis, people who live in suburban areas are thought to take advantage of their surroundings and therefore do not need to get away in order to grill some sausages or build a snowman. This is referred to as the ‘barbecue effect’ or ‘offsetting effect.’ This explanation runs counter to the concept of the compact city that, from the transport perspective, should translate into lower per-capita energy use than in more sprawling cities.

Sébastien Munafò, a researcher in the Urban Sociology Laboratory, wanted to challenge the barbecue effect and made it the subject of his thesis. He took two cities, Geneva and Zurich, and divided them into three sectors: downtown, inner suburbs and outer suburbs. He then analyzed the daily and occasional comings and goings of residents, using figures from the “Mobility and Transport Microcensus” that is carried out every five years by the Swiss Federal Statistical Office. When it comes to daily commuting, no surprises: urbanites don’t go far – nearly everything is close by – while suburban dwellers rack up the kilometers…

“The barbecue effect implies that one does not freely choose where one lives and that city dwellers find themselves prisoners of unpleasant surroundings,” said Sébastien. “But in most cases, city living is very expensive. Those who live there are thus making a choice, one that offers advantages as well.” This means people decide where to live as a function of their lifestyle: the suburbs for those who like to be close to nature, or the city for those who prefer its density and diversity. And having a little patch of green nearby doesn’t keep urbanites from travelling extensively, because in the end that is also part of their lifestyle. “One could say that there is an urbanity effect: the more we live in cities, the more regularly we move around, the more comfortable we are travelling, and the better access we have to reliable means of transportation,” concludes the researcher.

Two quick thoughts:

  1. It would be very interesting to see whether this holds up across cities and countries. For example, the researcher suggests city living is quite expensive in Switzerland (and generally elsewhere in Europe) and this means residents are wealthier. In the United States, there are definitely wealthier city residents but large cities are also the places where many of the poorest neighborhoods are located and the lack of resources severely limits travel.
  2. I would be in favor of more theories or mechanisms having clever names like “the barbecue effect.” It is probably too colloquial for many researchers but it is more accessible to the public. Plus, it invokes food and this can’t be a bad thing.

Good news about Chicago traffic and congestion – but due to new criteria

A new report from a group named CEOs for Cities claims that Chicagoans spend the least amount of time in rush-hour traffic compared to other major cities:

The report’s ranking of mobility in 51 cities found that Chicago-area residents spend the least time in rush-hour travel. In Chicago and some of the other best-performing cities — including New Orleans, New York, Portland, Ore., and Sacramento, Calif. — commuters typically spend 40 fewer hours a year in peak-hour travel than the average American, the report said.

In metro areas with the worst urban sprawl — including Nashville, Detroit, Indianapolis and Raleigh, N.C. — residents spend as much as 240 hours per year in rush-period travel on average because commuting distances are much longer, said the report, which was produced with the support of the Rockefeller Foundation.

This seems to be contrary to other studies I’ve seen that suggest Chicago is quite congested. One reason this study might have different results is a new criteria in the methodology.

The report’s author criticized other mobility studies that focus on the amount of traffic congestion in a region without factoring in travel distance.

The Urban Mobility Report, issued every two years by the Texas Transportation Institute, is regarded by many experts as the authoritative voice on traffic congestion issues. The report consistently ranks the Chicago region as the second or third most-congested area of the nation. It does not account for travel distance.

I am left wondering whether travel distance an important factor to include…

The Infrastructurist comments on the disparities in the two sets of rankings.