Abstract. The research infrastructure IAGOS (In-Service Aircraft
for a Global Observing System) equips commercial aircraft with instruments
to monitor the composition of the atmosphere during flights around the
world. In this article, we use data from two China Airlines aircraft based
in Taipei (Taiwan) which provided daily measurements of ozone, carbon
monoxide and water vapour throughout the summer of 2016. We present time
series, from the surface to the upper troposphere, of ozone, carbon monoxide
and relative humidity near Taipei, focusing on periods influenced by the
passage of typhoons. We examine landing and take-off profiles in the
vicinity of tropical cyclones using ERA-5 reanalyses to elucidate the
origin of the anomalies in the vertical distribution of these chemical
species. Results indicate a high ozone content in the upper- to middle-troposphere
track of the storms. The high ozone mixing ratios are generally
correlated with potential vorticity and anti-correlated with relative
humidity, suggesting stratospheric origin. These results suggest that
tropical cyclones participate in transporting air from the stratosphere to
troposphere and that such transport could be a regular feature of typhoons.
After the typhoons passed Taiwan, the tropospheric column was filled with
substantially lower ozone mixing ratios due to the rapid uplift of marine
boundary layer air. At the same time, the relative humidity increased, and
carbon monoxide mixing ratios fell. Locally, therefore, the passage of
typhoons has a positive effect on air quality at the surface, cleansing the
atmosphere and reducing the mixing ratios of pollutants such as CO and O3.
POPULATION GENETICS OF ALLOZYME VARIATION IN NEUROSPORA INTERMEDIA