Study: Western U.S. smog originates across the ocean in Asia

Pollution is a global problem, and that reality is highlighted by a new study indicating smog in western U.S. states originates from Asian countries across the ocean. The movement of this pollution from Asia to the U.S. is curbing the latter country's emission-reduction efforts. In some cases, pollution coming primarily from China and India is causing 65-percent of the ozone pollution in western U.S. states.

There's one particular type of pollution that appears to be a high problem in this regard: nitrogen oxides, the byproduct of which is ozone after being broken down by the sun. North American countries have been working hard to cut their nitrogen oxide pollution, thusly decreasing ozone, but that decrease (to the tune of about 50-percent) is being offset by the high levels produced in India and China.

The amount of nitrogen oxides pumped into the environment in Asian countries has tripled over the last nearly 30 years. Ultimately, that pollution is found to be a 'major driver' in the ozone levels found in western U.S. states. The end result can be damage to lungs, asthma irritation, damage to crops, and more.

The study highlights the necessity in approaching pollution problems with a global perspective — we all share the same globe and no nation's pollution remains limited to that nation. China has vowed in past months to work on decreasing its pollution levels, helping address the issue.