Antarctic Ozone And Vertical Structure Of Atmosphere

Since the discovery of the Antarctic ozone hole, more attention has been put on long-term influences of ozone on climate and earth environment. The ozone sounding experiments has been carried out 56 times during IPY years and the ozone column has been observed automatically from 1993 to 2008 at Zhongshan station. Compared with the referred observations at Syova station and satellite-based data, the quality of ozone data was validated. Based on this data, this paper analyzed the temporal trend of Antarctic ozone hole and its impact factors during the last 30 years; identified the tropopause height using different definitions; suggested the seasonal variation of ozone and temperature in the stratosphere and troposphere; and investigated the planetary boundary layer structure and the vertical distribution of ozone, water vapor and temperature. Major conclusions are as follows:1. Compared with ground-based ozone column, the average of satellite-based data is slightly smaller and OMI-TOMS algorithm data is preciser than OMI-DOAS.2. The analysis shows that the ozone column above the balloon-burst height can calculate with MLS data instead of the SBUV data, which is generally used in Antarctica. Then we found that the integrated ozone column from sounding experiments is in accordance well with the ground-based. The ozone values from recommended satellite profile are 20%, 10% and 10% higher than the sounding data at 215hPa, 100hPa and 68hPa respectively; additionally, the temperature differences between the two datasets are -3k-2k at all layers.3. Statistical analysis showed that the size of Antarctic ozone hole (OHS) increased rapidly from 1980s to 1990s, then becomed to increase slowly in the late 1990s and remains stable in the 21st century. We speculated that the Antarctic ozone hole may disappear in 2070 depending on the relationship between OHS and stratosphere ozone depletion substances as well as stratosphere temperature.4. The thermal tropopause (LRT) and ozone tropopause (OT) were at 7.9km and 7.4km, respectively. Both tropopause pressure and temperature showed obvious seasonal variations, with higher tropopause altimeter and lower tropopause temperature in winter. The ozone and temperature at 25km were showing a same feature of seasonal variation, but this was reverse at 15km, indicating the ozone depletion mainly occurs at the bottom of stratosphere.5. The altimeter with maximum ozone concentration decreases gradually from summer to winter, because of the large-scale subsidence from stratosphere in polar region. We estimated the sinking rate ¹.8km/month in the upper stratosphere and ¹.2km/month in the lower stratosphere by ozone data. Troposphere ozone showed higher concentration in winter and lower in summer, which may be induced by NOx photochemical destruction and stratosphere downward transport.6. The convective boundary layer (CBL) height can reach 600m a.s.l. in summer at Zhongshan station,which is higher than that in the interior of the Antarctica; The annual mean boundary height is about 1500m a.s.l., and the ozone concentration peak shows at ⁵00m elevation which may have some kind of relation to the stability of boundary layer structure.7. The Louis scheme can simulate the turbulent fluxes near surface layer preferably over the Antarctic ice sheet; snow surface obtained more energy from atmosphere than releasing to atmosphere in the form of sensible heat flux; surface roughness z0 is 4.54×10^-4 m and drag coefficient Cd is 1.7×10^-3 in the near-neutral conditions. It displays that larger surface roughness and drag coefficient occur in the coast of the Antarctic ice sheet due to the surface melting in summer.