西沙群岛砗磲壳体碳、锶同位素研究及其对比

本文系统地测定了西沙群岛中双壳类鳞砗碟壳体碳、锶同位素，结果发现鳞砗碟壳体的碳、锶同位素的生长变化曲线表现出明显的周期性，碳同位素受到鳞砗碟新陈代谢作用的影响，幼年时期壳体的δ^13C变化，幅度小于发育期，这主要是由于鳞砗磲体内在幼年期能量的消耗大于发育期。通过与其壳体上的生长纹的对比，碳同位素的周期就是生物年生长周期。锶同位素的周期性主要是由于附近大陆年周期性降雨量的变化所引起的，它不受生物生长作用的影响。     

CLIMATE ANOMALY RECORDED IN GULIYA ICE CORE AND ENSO EVENTS

Examination of ENSO events and the accumulated precipitation and δ~(18)O values recorded in theGuliya ice core,China,shows that the relationship between the occurrence of ENSO events and theprecipitation anomaly in Guliya is significant.In the years of El Nino events,the anomalies ofprecipitation and δ~(18)O values in the Guliya ice core were negative anomalies,that is,the ENSO eventsare related to the deficit of precipitation as well as low temperature in the western China.     

A PRELIMINARY STUDY OF SNOW MASS VARIATIONS IN CHINA OVER THE PAST 30 YEARS

Daily snow data for 2300 climate stations covering the period from 1951 through 1980 have been used to monitorand diagnose secular variations,year-to-year fluctuations,and the spatial characteristics of snow variation trends inChina.An examination of time series reveals that there is a strong teleconnction to ENSO,to major volcanic eruptions,as well as to the CO_2-induced warming.The country-wide snow mass variations are positively correlated with globalmean temperature,increasing during the current warming period and decreasing during the recent cooling period priorto the mid 1960s.A synchronous relationship exists between El Nino/Southern Oscillation and snowy winter in China.The year-to-year snow fluctuations seem to be generally out of phase with volcanic activity.The anomaly map showsthat snow mass increased in high altitudes and moist regions,while it decreased in arid lowland and the southern bounda-ry zone during the warming period.The potential CO_2-induced changes in snow mass will further aggravate the regionaldifferentiation between high mountains and lowlands,between moist and arid regions.The number of snow cover dayswill decrease in the northern lowlands,and snowfall will increase in the Qinghai-Xizang Plateau,high mountains,andthe lower reaches of the Changjiang(Yangtze)River.     

恭贺中国现代冰川学研究的启蒙者、俄罗斯冰川学家道尔古辛教授百年华诞

2011年5月是俄罗斯著名冰川学家列奥尼德.德米特里耶维奇.道尔古辛(Leonid Dmitrievich Dolgushin)教授百年华诞,道尔古辛教授是享誉世界的著名冰川学家,也是中国现代冰川学研究的启蒙者.道尔古辛教授1911年5月24日出生于俄罗斯乌德穆尔特(Ud-murtia     

黄河上游春季径流的特征

本文指出,在唐乃亥以上的黄河上游干流融雪径流是3月下旬至6月上旬期间径流量的主要成份,所占比例在40％以上。据此,对NOAA/TIROS气象卫星云图的积雪遥感信息应用于黄河上游春季融雪径流预报进行了尝试。根据1987年龙羊峡水库实测资料验证,预报精度在80％以上,基本符合业务预报要求。