We’ve just landed in Busan/Pusan, South Korea, after a bumpy crossing. We could turn this into a travel blog - and we will include a bit about Korean air quality. But given the country has recently been in the news due to issues relating to extreme weather, we thought we’d look at the effects of weather on air quality.
Put simply: sun can cause chemical reactions in pollution particles, particularly ozone; rain can help to wash away particulate matter (but of course it still ends up somewhere); wind obviously moves pollution from one place to another (even from one side of the street to the other); and temperature affects the height of the boundary layer of the atmosphere, which effectively traps pollution, with colder temperatures leading to a lower layer meaning the pollution is trapped in less space. Apologies to any meteorologists or other experts out there who know it’s considerably more complicated than this!
On the matter of the boundary layer, we’ve both been reading Tim Smedley’s book ‘Clearing the air’ which has a great explanation, including explaining how it contributed to the Donora Disaster. We plan to do a review of the book in a future blog.
Whether the weather
Although weather conditions can exacerbate or ameliorate air pollution, it is our burning of fossil fuels that makes the pollution in the first place. Very little is caused by ‘natural phenomena’ such as sand storms or volcanoes.
Weather conditions also drive different human behaviours, eg more heating in cold weather. So there is a double whammy in the winter. We admit we were surprised about this seasonal variation, having intuitively thought that pollution would be worse in the summer.
So how is the air quality in South Korea? Unfortunately air quality is worse in South Korea than Japan, although the worst areas are around Seoul rather than Busan where we landed (above: the boat ride was very choppy and boy were we happy to see dry land).
The country has the unenviable distinction of being rated the worst in the OECD group of advanced economies. Without the pollution coming from China, it would still be below average in the OECD.
Biting dust
The impact of China on Korean air seems to be something of a controversy. Many studies appear to suggest Korea’s biggest neighbour is the culprit of a significant amount and public perception is that it causes the majority. There is even an interesting article showing how tracking the discussion of such pollution trends can teach us about the spread of misinformation.
Along with all the usual local pollution sources (vehicles, industry), it appears that Korea’s 61 coal fired power stations contribute significantly to the problems, particularly around Seoul. Like Paris, Seoul has trialled some measures for particularly high pollution episodes like making public transport free, but it seems they didn’t work so were dropped. The government is taking steps to reduce the use of coal and air quality has improved over time.
Such an interesting article on the unconscious bias towards China as the major source of PM!