Why Has Mexico City Banned 40% of its Cars?

At the beginning of the month, the authorities in Mexico City issued only its second air pollution alerts in a decade. As a result, 40% of all cars have been ordered off the city’s roads until June. Furthermore, many industries from the capital city and the surrounding states have been compelled to cut emissions during the same time period in a bid to improve the deteriorating conditions in and around the metropolis.

The increased ban comes on the back of a pre-existing incentive to cut traffic by 20%, through the outlawing of one in five cars from the city streets on each day of the week, with an additional ban in place on one Saturday of every month.

A Worsening Problem

Back in 1992, Mexico City endured a reputation as the most polluted city in the world. In the wake of the climate talks in Rio de Janeiro that same year, the city made efforts to address its disastrous atmospheric problems and in 2008, the nation reiterated its intentions to cut emissions in half by 2050.

Despite such ambitious plans, air quality in the country (and in particular in its capital) has regressed over recent years. In March, the authorities were forced to call their first alert in more than a decade after pollution reached dangerously high levels. The new measures were brought in as a result, but despite their implementation, air quality suffered again in April and at the beginning of this month.

The most recent alert was instigated when ozone levels climbed as high as 161 – 11 points above the 150 threshold for declaring a warning. The threshold had been lowered only a month before (down from 190) as the country looks to get serious about this very real threat to the health and livelihood of its 20 million inhabitants.

Normally, around 5.5 million cars are in circulation on the city’s roads on any given weekday. With the new ruling, this figure should theoretically fall to roughly 3.3 million, which the government hopes will be enough to see a marked improvement in ozone levels.

Industry Told to Cut Emissions As Well

Traffic is not the only contributing factor in the generation of unprecedented ozone levels - the influence of oil and gas emissions on ambient non-methane hydrocarbons as a result of industry should not be underestimated, either.

The Mexican authorities have called on a whole host of different factories, including those in the sectors of pharmaceuticals, chemicals, cement, fossil fuels and other power generation plants, to slash their emissions by 40%.  

Earlier this year, five companies (four of which are subsidiaries of North American firms) refused the Mexican authorities access to information about their emission figures. As a result, the government is considering shutting down all five operations as a message to other companies who may be considering not complying with the regulations.