Similarly to the case of 21:00 LST, synoptic-scale shrunken atmospheric layer of 100 m could force nocturnal surface inversion layer in the city to be further more shrunken at night.
Particularly, shortly after sunset around 17:00 LST in Korea, nocturnal cooling of the ground surface causes cooling of air masses near ground surface and produces nocturnal surface inversion layer (NSIL), which is much more shrunken than the daytime thermal internal boundary layer (Figure 11(b)).
In the previous research by Choi and Choi , nocturnal surface inversion layer in the coastal basin of Gangneung city was developed to 200~250 m height over the ground surface in March.
At this time of year, the sun is above the horizon for more than 21 hours a day, hindering the formation of a surface inversion
. In winter, when the surface inversion
is strong (Wendler and Nicpon, 1975), the surface layer is semi-decoupled from the winds aloft, and the minimum wind speed of 1.2 m/s is observed.
For example, the strength of a surface inversion has been suggested to enhance Arctic amplification, by suppressing the cooling caused by longwave radiation escaping to space during the winter half of the year (Bintanja et al.
During cloud-free winter conditions, strong surface inversions form due to longwave surface cooling, while low clouds tend to generate elevated cloud-top inversions due longwave cloud-top cooling (e.g., Tjernstrom et al.
This implies that a weaker surface inversion became established downstream of the crater, assuming similar conditions at the inversion top.
The sloshing of the surface inversion was visualized by the infrared cameras on the crater rim (Fig.