A toxic type of outdoor air
The researchers measured human-caused air pollution around the world based on the difference in pollution levels between 1850 and 2000.
Now NASA has published a map, based on the results, that estimates the average number of deaths per 386 square miles per year due to air pollution.
Blue areas have experienced an improvement in air quality relative to 1850, and the dark brown areas have seen the most premature deaths.
NASA notes that the effect of air pollution can be seen "all areas where urbanization has added considerable quantities of PM2.5 to the atmosphere since the start of the Industrial Revolution."
Check it out:
NASA
The map informs extreme smog events, which are caused by short-term weather events merging with ongoing humans emissions.
In June Singapore was blanketed in smog spurred by illegal forest fires on Indonesia's Sumatra island.
Air pollution is a perennial problem in China, where the government has acknowledged that the poor air quality has led to "severe health and social problems such as 'cancer villages.'"
China may be the worst, but the map shows that many people may be much more vulnerable to hazardous pollution than they realize.