Successfully adding 11 new Chinese characters to Unicode (medium.com)

The geographic pictograph commentary of "9 ways to divide Taiwan" is rather interesting. The one that caught my eye was #6 where the island is divided between "PM2.5" and "Typhoon". The difference in air between where the island is either buffeted by either pollution from China or Typhoon winds.

Nice writeup. But I'd like to know what the character mean, what is the closest match in other version of Chinese and why were they forgotten.