Glaciochemical records from Naimona’Nyi ice core in the Himalayas     

LIU Yongqin  YAO Tandong  TIAN Lide  XU Baiqin  WU Guangjian 《地理学报》2006,16(4):465-471

A 6-m ice core was recovered in 2004 from the Naimona’Nyi Glacier, the middle Himalayas. Empirical orthogonal function (EOF) analysis on the major ion reveals that EOF1 represents the variations of majority of ions which may be originated from crustal aerosols. Comparing the calcium concentrations from the Naimona’Nyi with these from Dasuopu, East Rongbuk and Guliya ice cores, it is observed that calcium, a good indicator of the input of crustal aerosol in snow, concentrates mostly in the Guliya ice core located on the northern Tibetan Plateau, and gradually decreases from west to east in the Himalayas.  相似文献   

Glaciochemical records from Naimona’Nyi ice core in the Himalayas     

LIU Yongqin    YAO Tandong    TIAN Lide    XU Baiqin    WU Guangjian 《地理学报(英文版)》2006,(4)

Chemical records in ice and snow from polar ice sheets or mountain glacier can provide information about atmospheric composition, climate and environmental changes. Using glaciochemical records, the source of dust and moisture, and changes of atmospheric …  相似文献   

Precipitation extremes in the Yangtze River Basin,China: regional frequency and spatial–temporal patterns     

Yongqin David Chen  Qiang Zhang  Mingzhong Xiao  Vijay P. Singh  Yee Leung  Luguang Jiang 《Theoretical and Applied Climatology》2014,116(3-4):447-461

Regional frequency analysis and spatial–temporal patterns of precipitation extremes are investigated based on daily precipitation data covering 1960–2009 using the index-flood L-moments method together with some advanced statistical tests and spatial analysis techniques. The results indicate that: (1) the entire Yangtze River basin can be divided into six homogeneous regions in terms of extreme daily precipitation index. Goodness-of-fit test indicates that Pearson type III (PE3, three parameters), general extreme-value (GEV, three parameters), and general normal (GNO, three parameters) perform well in fitting regional precipitation extremes; (2) the regional growth curves for each homogeneous region with 99 % error bands show that the quantile estimates are reliable enough and can be used when return periods are less than 100 years, and the results indicate that extreme precipitation events are highly probable to occur in regions V and VI, and hence higher risk of floods and droughts; and (3) spatial patterns of annual extreme daily precipitation with return period of 20 years indicate that precipitation amount increases gradually from the upper to the lower Yangtze River basin, showing higher risks of floods and droughts in the middle and lower Yangtze River basin, and this result is in good agreement with those derived from regional growth curves.  相似文献