The Independent has an article on air pollution levels around the globe - The most toxic countries in the world in two maps.

Saudi Arabia ranked first with the world’s largest carbon emissions, and the highest recorded levels of pollution – even higher than China. Coming in at second is Kuwait, followed by Qatar, Bahrain and the United Arab Emirates. Many parts of Africa, such as Cameroon, Mozambique, Ethiopia, and, Tanzania report very little air pollution. ...

The study cross-referenced data for energy consumption, carbon emissions, renewable energy contribution, total energy supply, air pollution levels and the number of deaths caused by poor air quality levels.

The ABC has a report on Beijing's appalling air pollution problems (something DOnald Trump apparently hopes to see return to the skies of US cities) - . Perhaps they need to ban cars on alternate days again in order to see blue skies.

Heavy smog has engulfed large parts of northern China for a fourth straight day, with the environment ministry warning that some firms in the region were continuing to flout emergency restrictions and dozens of flights out of Beijing cancelled.

Paris is so smog afflicted it has made public transport free and limited the days drivers are allowed on the roads in a bid to reduce traffic congestion. Paris is also one of a number of city looking to ban diesel vehicles from use by 2025 - Mayors Of Paris, Mexico City, Madrid, & Athens Move To Ban All Diesel Vehicles By 2025.

To be clear on the first commitment, this would apparently apply to all diesel vehicles — including trucks, not just cars. The idea is to improve local air quality and also to reduce greenhouse gas emissions — which is what the C40 forum was initially formed for, the idea being to give mayors working to mitigate and prevent anthropogenic climate change a place to share notes, so to speak.

The mayor of Madrid, Manuela Carmena, commented on this: “The quality of the air that we breathe in our cities is directly linked to tackling climate change. As we reduce the greenhouse gas emissions generated in our cities, our air will become cleaner and our children, our grandparents and our neighbours will be healthier.”

Another article from a week or so ago, this one from The Independent - Haunting Asia, a brown cloud blots out sun.

A noxious cocktail of soot, smog and toxic chemicals is blotting out the sun, fouling the lungs of millions of people and altering weather patterns in large parts of Asia, according to a report released Thursday by the United Nations.

The byproduct of automobiles, slash-and-burn agriculture, wood-burning kitchen stoves and coal-fired power plants, these plumes of carbon dust rise over southern Africa, the Amazon basin and North America but are most pronounced in Asia, where so-called atmospheric brown clouds are dramatically reducing sunlight in many Chinese cities and leading to decreased crop yields in swaths of rural India, says a team of more than a dozen scientists who have been studying the problem since 2002.

Combined with evidence that greenhouse gases are leading to a rise in global temperatures, the report's authors called on governments rich and poor to address carbon emissions.

"The imperative to act has never been clearer," Achim Steiner, executive director of the United Nations Environment Program, said in Beijing, where the report, "Atmospheric Brown Clouds: Regional Assessment Report With Focus on Asia," was released.

The brownish haze, sometimes more than a mile, or 1.6 kilometers, thick and clearly visible from airplanes, stretches from the Arabian Peninsula to the Yellow Sea.

In the spring it sweeps past North and South Korea and Japan. Sometimes the cloud drifts as far west as California. The report identifies 13 cities as brown-cloud hotspots, among them Bangkok, Cairo, New Delhi, Seoul and Tehran. In some Chinese cities, the smog has reduced sunlight by as much as 20 percent since the 1970s, the report says.

Rain can cleanse the skies, but some of the black grime that falls to earth ends up on the surface of the Himalayan glaciers that are the source of water for billions of people in China, India and Pakistan.

The result: The glaciers that feed into the Yangtze, Ganges, Indus and Yellow rivers are absorbing more sunlight and melting quicker, researchers say.

According to the Chinese Academy of Sciences, those glaciers have shrunk 5 percent since the 1950s and at the current rate of retreat could shrink by an additional 75 percent by 2050.

Frogblog has some good quotes from a David Suzuki interview about air pollution.

Our lungs are made up of about 300 million capsules, or alveoli, and they are clustered around an alveolar stem like grapes. We have lots of these clusters in our lungs and we need them all to provide the surface area needed to come into contact with the air. If you flatten the alveoli of our lungs out into two dimensions, they would cover a tennis court. That is about how much surface area is wrinkled up in our lungs. Each alveolus is lined by a surfactant that reduces surface tension so that the air sticks to it. Immediately carbon dioxide rushes out of our bodies, oxygen and whatever else is in the air rushes in, and haemoglobin molecules in red blood cells grab on to the oxygen so that each beat of our heart can transfer that oxygen to every part of our bodies. And when you exhale you do not exhale all the air in your lungs. If you did that your lungs would collapse. About half of the air stays in your lungs even when you exhale.

The point I am trying to make is that you cannot draw a line that marks where the air ends and I begin. There is no line. The air is stuck to us and circulating through our bodies. We are air. It is a part of us and it is in us…

We think we are an intelligent creature, but what intelligent creature, knowing the role that air plays in our lives keeping us alive and connecting us to the past and into the future, would then proceed to use air as a garbage can and refuse to pay for putting carbon and all our pollutants into the atmosphere? We have much to reflect on the way that we use this sacred substance. It hurts me when I see young couples walking with a baby in a stroller and the baby’s nose is right at the level of the exhaust pipes of our cars. You might as well put a hose on the exhaust pipe and pump that stuff right into the baby’s body. Why are 15% of children in Canada now suffering with asthma? We are using the air as a toxic dump. We are air. Whatever we do to the air we do to ourselves.