Features of visibility variation at Great Wall Station,Antarctica  

作　　者：YANG Qinghua YU Lejiang WEI Lixin ZHANG Benzheng MENG Shang 

机构地区：[1]National Marine Environmental Forecasting Center [2]College of Hydrometeorology,Nanjing University of Information Science&Technology [3]Wuhan Meteorological Service

出　　处：《Advances in Polar Science》2013年第3期188-193,共6页极地科学进展（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant nos.41006115,41076128,41106164);the Chinese Polar Environmental Comprehensive Investigation and Assessment Programs(Grant nos.CHINARE2013-02-04,CHINARE2013-01-01)

摘　　要：The variation of visibility at Great Wall Station （GWS） was analyzed using manual observational data for the period of 1986 to 2012. Results show that the frequencies of occurrence of high （≥ 10 km） and low visibility （0-1 km） are 61.0% and 8.0%, respectively. Visibility at GWS shows an evident seasonal variation： The highest visibility between November and March, and the lowest visibility from June to October. Sea fog and precipitation are the main factors for low visibility during summer, whereas frequent adverse weather, such as falling snow, blowing snow, or blizzards, are responsible for low visibility in winter. The frequency of occurrence of low visibility has decreased significantly from 1986 to 2012. Conversely, the frequency of occurrence of high visibility has shown a significant increasing trend, especially during winter. The decreasing tendencies of fog, blowing snow, and snowfall have contributed to the increasing trend of high visibility during winter. Visibility at GWS exhibits significant synoptic-scale （2.1 to 8.3 d）, annual, and inter-annual periods （2 a, 4.1 a, and 6.9 a to 8.2 a）, among which the most significant period is 4.1 a. The visibility observed during 2012 indicates that instrumental observation can be applied in the continuous monitoring of visibility at GWS.The variation of visibility at Great Wall Station （GWS） was analyzed using manual observational data for the period of 1986 to 2012. Results show that the frequencies of occurrence of high （≥ 10 km） and low visibility （0-1 km） are 61.0% and 8.0%, respectively. Visibility at GWS shows an evident seasonal variation： The highest visibility between November and March, and the lowest visibility from June to October. Sea fog and precipitation are the main factors for low visibility during summer, whereas frequent adverse weather, such as falling snow, blowing snow, or blizzards, are responsible for low visibility in winter. The frequency of occurrence of low visibility has decreased significantly from 1986 to 2012. Conversely, the frequency of occurrence of high visibility has shown a significant increasing trend, especially during winter. The decreasing tendencies of fog, blowing snow, and snowfall have contributed to the increasing trend of high visibility during winter. Visibility at GWS exhibits significant synoptic-scale （2.1 to 8.3 d）, annual, and inter-annual periods （2 a, 4.1 a, and 6.9 a to 8.2 a）, among which the most significant period is 4.1 a. The visibility observed during 2012 indicates that instrumental observation can be applied in the continuous monitoring of visibility at GWS.

关 键 词：Great Wall Station ANTARCTICA VISIBILITY sea fog blowing snow 

分 类 号：P427.2[天文地球—大气科学及气象学]