A Comparison of Properties of a Cyclonic Event Fog and an Anticyclonic Event Fog in July 2022 at Sable Island, Nova Scotia

The Fog And Turbulence In Marine Atmosphere (FATIMA) field project took place during July 01-31 2022 over Sable Island located 160 km off Nova Scotia. FATIMA measurements on the island included many special in-situ and remote sensing measurements. Of 16 fog occurrence events in July 2022, only 2 were radiation-fog events occurring around sunrise under clear skies. The other 14 fog cases occurred within an extended event under a low overcast cloud with occasional fog and mist under a cyclonic setting or an anticyclonic setting. The physical factors of a cyclonic event are compared with an anticyclonic event. All physical factors have substantial differences between the cyclonic and the anticyclonic events. These include 1000 hPa and 900 hPa convergence and vertical velocity, radiation fluxes, liquid water content, precipitation microwave rain radiometer, turbulence kinetic energy, turbulent heat fluxes, and the gradient Richardson number that occurred in the marine layer with surface-based air temperature inversion. The object is to present the differences between the cyclonic event and the anticyclonic event and understand why they occur.