Lapdog;From your link.......

Lapdog;

From your link.... http://www.nytimes.com/1991/11/25/world/mexico-city-emits-more-heat-over-pollution.html


""It is no small thing," Mr. Camacho kept saying, that in the last few years the Government had switched the city's microbuses to unleaded fuel, put all of its private cars out of circulation one day a week, shut the area's biggest oil refinery and planted 12.6 million trees in one year.

Scientists agree that those steps have helped to reduce contaminants like lead and sulphur dioxide. But Mexico City's most serious pollutant is ozone, formed when hydrocarbon and nitrogen oxide emissions are exposed to sunlight. And from 1986 to 1990, the number of days on which the city surpassed acceptable norms for ozone leaped from 130 to 303."
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>>CO2 does not even get a mention!

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Bit more info for you...

"Summary: The atmospheric pollution in Mexico City is one of the most severe air pollution cases in the world. The pollution levels are often above air quality standards and therefore it is urgent to find strategies to control them. The most important air pollutants are ozone and it's precursors (HC and NOx).

Objectives: This case study will try to analyze the relationship between the concentration of CO in Mexico City's air and parameters such as energy (fuel) consumption for transportation or the topology of the road network. Moreover, the case study will look at the projections for reductions in CO concentration levels caused by the implementation of strategies such as use of better fuels, increased use of catalytic converters in vehicles, and better transit conditions. "

CO = Carbon Monoxide, this is real AIR POLLUTION, again nothing to do with CO2 (Carbon Dioxide).

http://www.ess.co.at/GAIA/CASES/MEX/index.html