Detection of air within the northern hemisphere polar vortex at Wakkanai and at Tsukuba, Japan

Abstract

Intensive ozonesonde observations were conducted at Wakkanai(45.4°N , 141.7°E ), the northernmost city of Japan, during the period 15th to 24th February 2001. Air in the polar vortex passed over Wakkanai on 19th February 2001 on the 700K isentropic surface. An increase of potential vorticity and a decrease of ozone mixing ratio on the 700K isentropic surface over Wakkanai were observed on the same day, 19th February 2001. On the other hand, on the 450K isentropic surface the air in the polar vortex passed over Tsukuba(36.1°N , 140.1°E ), Japan, where the Aerological Observatory and the Meteorological Research Institute are located, on 20th February 2001. Decrease of the ratio of observed HCl(hydrogen chloride) to HCl estimated from HF(hydrogen fluoride) and increases of the potential vorticity and ozone mixing ratio on the 450K isentropic surface were observed over Tsukuba on 20th February 2001. These facts indicate that the polar vortex passed over Tsukuba on the 450K isentropic surface on 20th February 2001. Observations show that the polar vortex on the 700K isentropic surface existed over Europe and Siberia on 14th February 2001 moved eastward, and reached Wakkanai, Japan on 19th February 2001. Observations also show that the polar vortex on the 450K isentropic surface found over Europe and Siberia on the 14th moved eastward and reached Wakkanai, Japan between 15th and 20th February 2001 and covered Tsukuba, Japan on 20th February 2001. The ozone mixing ratio derived from ozonesonde data shows the possibility of decrease of ozone mixing ratio with ozone destructive chemical reactions in the northern hemisphere polar vortex on the 450K isentropic surface