(July 9, 2012) Satellite
measurements show that nitrogen dioxide in the lower atmosphere over parts of
Europe and the US has fallen over the past decade. More than 15 years of
atmospheric observations have revealed trends in air quality.
As the
world’s population increases, economies in many countries are also growing and
populations are concentrating in large cities. With the use of fossil fuels
still on the rise, pollution in large cities is also increasing.