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Measurements of column amounts of ozone, and UV-B radiation by using Brewer Ozone Spectrophotometer over Zhongshan Station (69.38°S, 76.37°E), Antarctica in the 1993 “Ozone. Hole” are introduced. Low total ozone amount near or below 200 DU had been detected from August to November with focus moon light or direct solar light. High coherent variation between the ozone column amounts and the temperatures within altitude from 70 hpa to 50 hpa is very obvious. UV-B radiation is greatly controlled by the Solar Zenith Angle (SZA) t total ozone amount as well as the sky conditions. Preliminary statistics analysis shows that noontime biologically weighted damaging UV-B (DUV-B) dose rate is a negative exponential function of the ozone slant column abundance (OSCA). The ratios of noontime irradiance for wavelength at 300.5 nm to that at 323.5 nm reveal that ozone is one of the most important factors for the surface UV-B enhancing during the ozone depletion period.
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Having analysised the data collected by our survey ship “Ocean IV” in the Bransfield Strait in 1991, we recognized that the geomorphology, gravity and magnetic anomalies trending NE direction along bandings. The sediments in the Bransfield Strait can be subdivided into two sequences:the first rifting sequence and the second rifting sequence. The basement was faulted into a half-graben in northwestern side of the Bransfield trough. Considering the crustal structure crossing the South Shetland Islands,the Bransfield Strait and the Antarctic Peninsula, we propose a two-phase rift-ing tectonic evolution model and a layered-shear model for the lithospheric deformation under the effects of extensional stress field.
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This paper deals with the results of the MT observations in the region of Zhongshan Station,Larsemann Hills area. East Antarctica and points out that the lithosphere thickness of the Larsemann Hills is 140 km and the crustal high conductivi, ty layer is situated in 22 km.
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Abstract A comparison of theoretical seismograms under discussion with four tele- seismograms recorded by WWSSN of SBA (New Zealand) and SPA (U. S. A.),shows that the crustal thickness beneath South Pole is a double-layered structure,about 45 kmi crustal thickness below the Ross Sea Beach,a single structure,is about 24 kmi and at the depth of 350~450 km there exists a low velocity layer. The above results indicate the different tectonic characteristics on both sides of Antarctic Transantarctic Mountains.
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In this review, the observaticmal facts about pulsating aurorae are summarized and discussed in the frame of the recent development of the theories which intend to explain the mechanism of auroral pulsations. Although new data are available some key observations in the magnetosphere are still missing in order to identify the wave mode to precipitate electrons into the atmosphere and in order to understand the role of magnetospheric plasma in producing pulsating aurora. It appears that the Coroniti-Ken- nel or micropulsation theory needs to be re-visited although the so-called flow cyclotron maser model seems to explain many of the characteristics of auroral pulsations.
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In this paper Pi2 pulsation events at Great Wall Station of Antarctica are analyzed from August 16,1990 to November 20, 1990. Their main characteristics e. g. occurrence frequency, frequency, and polarizations are recognized. The mechanism of excitation for Pi2 pulsations at Great Wall Station is here discussed theoretically.
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Experiments and observations on reproduction of Antarctic krill,
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This paper reports the results of the absorption spectral analysis of Ulothrix sp. attached to the rocks from the intertidal zone in front of Great Wall Station,Antarctica in February 1989,and the benthic diatoms growing on small stones and on the edge of swamps of that zone. Six kinds of pigments were separated and identified in benthic diatoms. They are carotene, chlorophyll-a, fucoxanthin, chlorophyin, neoxanthin and chlorophyll-c. Nine kinds of pigments were identified in Ulothrix sp.. They are carotinoid, pheophytin, chlorophyll-a, -b, chlorophyllin, chlorophyllide-a, neoxanthin, chlorophyll-c and pheophytin-c. The intertidal benthic diatoms and Ulothrix sp. have specific absorption spectra and there are also marked differences in the composition of algal pigments they contain. Since the pigments of marine algae show differences in their absorption spectra, the absorption spectrum can be used to identify the species of marine algae.
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