https://phys.org/news/2018-06-tropical-cyclones-affect-air-quality.html

Dr. LI further explained that tropical cyclones are one of the strongest forms of atmospheric convective activity. Their landfall and associated rainfall favor the dispersion of pollutants, whereas the descending motion in their outer periphery favors the accumulation of pollutants. Actually, the impact of tropical cyclones on PM10 and ozone is different, related to differences in emission sources and their transportation pathways.

"When a TC is located southwest of Taiwan, the descending motion moves to the north of Hong Kong, as compared to the presence of a TC over Taiwan, reducing the deposition of ozone and its precursors from remote coastal regions," explains Associate Professor ZHOU.

                                                            
                                    
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