Archive

30 December 1999, Volume 11 Issue 4 Previous Issue    Next Issue
---
Contents


For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

Contents

Select

DYNAMICS OF SOIL MOISTURE STATUS IN THE MARITIME ANTARCTIC ZONE 1999, 11 (4):  241-254.  Abstract ( 1359 )   PDF (288KB) ( 1289 )   In situ observation of dynamic changes in free water contents of soils at two sites (Eutric gelic Regosol and Dystri gelic Cambisol) was carried out in the ice free area of the Fildes Peninsula, King George Island, the maritime Antarctic zone,by use of the specially developed moisture sensing probes as sensors. The variation of freeze thaw and moisture status of the soils, caused by site differences, was demonstrated. In addition, the possible differences of freeze thaw cycle and moisture status of the soils between two years, resulting from variation of climatic factors etc., were discussed. Finally, several general conclusions on moisture regimes and dynamic changes in free water contents of soils in the studied area were tentatively drawn. [WT5HZ] Related Articles | Metrics

Select

VOLCANIC ERUPTIONS RECORDED IN AN ICE CORE FROM COLLINS ICE CAP,KING GEORGE ISLAND,ANTARCTICA 1999, 11 (4):  255-263.  Abstract ( 1348 )   PDF (263KB) ( 1185 )   Careful mineral and structural analyses have revealed the characteristics of volcanic ash in the 9 horizons of a 80.2m ice core from Collins Ice Cap,King George Island,Antarctica. Under the assumption of steady state,Dansgaard Johnsen flow model was employed to date the core. The volcanic eruptive sequence established for South Shetland Islands region since A.D.1650 shows that 7 volcanic eruptive cycles could be distinguished during the past 340 years,as covered by the ice core. It seems that during the period of 1875-1925 there were frequent volcanic activities,with perhaps many eruptions at the Deception Island. The years between A.D.1650 to A.D.1800 appeared to be a quiet period,followed by an unsteady century in volcanic action. The past century is basically a tranquil era except for two turbulent epochs at the beginning of the century and in the 1950-70s. Many of the volcanic eruptions in the ice core sequence are found in the previously reported records for this region. A few of that are not in the records should be further investigated. The absence of 1967-1970 eruptive trace in the core suggests that the volcanic eruptions obtained by present study could still be the minimum number of the actual eruptions,although the general outline was exhibited by present study. Related Articles | Metrics

Select

A STUDY ON THE 6-YEAR OBSERVATION OF THE SPRING OZONE DEPLETION AT ZHONGSHAN STATION, ANTARCTICA 1999, 11 (4):  265-274.  Abstract ( 1281 )   PDF (452KB) ( 1164 )   WT5BZ]Based on the 6 year total ozone data set from the observations by using the Brewer ozone spectrophotometer and the TOMS, an summarily analysis study on the spring ozone depletion at Zhongshan Station(69.37°S,76.38°E),Antarctica has been presented in this paper. Our work confirms that the large ozone depletions over Zhongshan Station are associated with the dynamical process of the polar vortex, and this makes the large daily ozone variations during the spring period. Data set from the Brewer and TOMS is generally consistent with each other, however, TMOS data set is about 6~10DU higher than that of Brewer's observations. Surface global weighted UV B dose rate is higher in spring season than that on the summer solstice due to the anomalous spring ozone depletion. UV B irradiance within 300-305nm band is more sensitive to the ozone depletion than that within 320-325nm band. [WT5HZ] Related Articles | Metrics

Select

EFFECT OF "THREE POLE" STRONG SIGNAL CHARACTERISTICS ON CLIMATE CHANGE 1999, 11 (4):  275-284.  Abstract ( 1275 )   PDF (626KB) ( 1394 )   WT5BZ]Earlier stage “three pole” strong signal characteristics that affect regional climate changes in East Asia and China are disclosed in this paper. The cross correlation feature and coupling effect among sea ice of North and South pole and water thermal station on plateau surface is discussed as well. Comparison among the roles of these three earlier stage factors in summer climate change in china is carried out. The formation mechanisms of global climate change and regional climate change of china are investigated from the aspect of qualitative correlation mode of global sea land air ice. Related Articles | Metrics

Select

REBUILDING AND ANALYSIS OF GPS MONITOR NETWORK FOR CRUST DEFORMATION IN THE FILDES STRAIT FAULTAGE,WEST ANTARCTICA 1999, 11 (4):  285-290.  Abstract ( 1528 )   PDF (274KB) ( 1394 )   In this paper,In order to monitor the Fildes Strait faultage crust deformation effectively,the two dimension deformation monitor Network was changed to three dimension deformation monitor Network using the GPS technology. Collecting the GPS data,data analysis and process are discussed. The result show that the accuracy is better than 3mm in the level,better than 6mm in the vertical. Building the spacious GPS monitor Network in the Antarctic is feasible in researching Antarctic crust kinetic deformation. [WT5HZ] Related Articles | Metrics

Select

SUMMER WEATHER CHARACTERISTICS OF GROVE MOUNTAIN AREA IN EAST ANTARCTICA 1999, 11 (4):  291-300.  Abstract ( 1670 )   PDF (499KB) ( 1360 )   WT5BZ]The summer weather characteristics of Grove Mountain are presented based on the data obtained by Chinese National Antarctic Research Expedition (CHINARE) in Jan. 1999. The result shows that the pattern of diurnal variation of temperature and the prevailing wind direction in Grove is similar with that in Zhongshan Station. However, the daily range of temperature and strong wind frequency are much higher than that of Zhongshan Station. The change of wind direction correlates with weather system that impacted Grove area. The warm and wet air from northern parts often causes the precipitation. The clear weather appears controlled by eastern winds in January. [WT5HZ] Related Articles | Metrics

Select

THE ARCTIC SEA ICE,CLIMATE AND ITS RELATION WITH GLOBAL CLIMATE SYSTEM 1999, 11 (4):  301-310.  Abstract ( 1625 )   PDF (473KB) ( 3257 )   The Arctic sea ice distribution, thickness variation, surface characteristics and snow cover variation as well as the climatology and its regional differentiating are discussed according to previous research results and our observation in the Arctic Ocean, August 1999. A comparison of sea ice between Arctic and Antarctic areas is conducted. It can be found that, the climate trend in Arctic Ocean is different from the areas around the ocean. This is mainly due to alternate distribution of ice floes and open water in Arctic Ocean in summer, the drifting, melting and absorbing heat of sea ice, which balance the temperature fluctuation around. Related Articles | Metrics