西北太平洋副高东西变动与西南地区降水的关系

西北太平洋副热带高压（简称副高）位置的异常变动对东亚和中国气候有十分重要的影响。为进一步认识副高东西变动对中国西南地区降水的影响,根据东亚—西北太平洋地区高低层大气环流的季节特征,选取700 hPa不同关键区区域平均相对涡度定义了一个新的表征副高位置东西变动的VORT指数。分析发现:该指数不仅能客观定性地表征副高反气旋环流位置的东西变动,而且能反映副高与东亚经向环流变化的关系,副高偏东（西）时,东亚呈负-正-负（正-负-正）经向异常波列。与其他副高指数相比,该指数能较好地反映夏季中国东部雨带位置的季节性移动,并与西南地区降水呈显著相关,对西南地区降水变化有指示意义。其中,6月和7月的相关非常显著,副高偏西时,6月四川西部和南部、云南中北部地区降水偏少,贵州大部降水偏多;7月四川北部和东部、贵州东北部降水偏多,而云南中部和西北部降水偏少,反之亦然。进一步分析还发现,副高与海温的关系与副高活动的位置有关,副高越偏北,与海温的关系就越弱。     

春季对流层温度的季内和季节以上分量对南海夏季风爆发的年代际变化的相对影响

南海夏季风爆发时间在1993/1994年出现显著的年代际提早, 探讨了大气要素场的不同时间尺度分量季节演变的年代际变异对南海夏季风爆发时间的年代际变异的相对影响作用。南海夏季风爆发时间的年代际提早与南海季风区对流层经向温度梯度季节性逆转的年代际提早有密切联系。南海季风区5月中对流层经向温度梯度年代际增强主要由季风区北部温度的年代际显著增暖造成。季内分量和季节以上分量对1993年之前南海季风区经向温度梯度逆转及加强时间偏晚的作用同等重要。经向温度梯度距平的季节以上分量主要源于季风区北部温度相应分量的贡献, 而季节内分量则主要由南部相应分量影响所致, 并由25~90 d分量所主导。季节以上分量对1994年之后南海季风区经向温度梯度逆转及加强时间偏早的贡献要大于季节内分量的贡献。经向温度梯度距平的季节以上分量和季内分量对总距平的正贡献都主要来自于季风区北部温度相应分量。两种季内低频分量对温度梯度季内分量的贡献率相当, 10~25 d分量主要由南海北部温度相应分量所主导, 25~90 d分量对总距平的正贡献也源自北部分量。准双周振荡分量对各年代南海夏季风爆发具有明显的触发作用。      

南海季风爆发的年代际转折与东亚副热带夏季降水的关系

利用1979—2016年NCEP再分析资料, 分析了南海季风爆发的年代际转折与东亚副热带夏季降水的关系。结果表明:南海夏季风爆发时间在1993/1994年出现年代际转变, 1979—1993年爆发时间相对偏晚, 夏季华南降水偏少, 长江中下游至日本南部降水偏多; 1994—2016年爆发时间偏早, 夏季华南降水偏多, 长江中下游到日本南部降水偏少。南海季风爆发时间年代际转折与夏季东亚副热带降水关系可能受到菲律宾越赤道气流强度的调控, 季风爆发时间与菲律宾越赤道气流有显著正相关, 且均在1993/1994年间存在年代际转变。在1994—2016(1979—1993)年南海夏季风爆发偏早(晚), 菲律宾越赤道气流偏弱(强), 澳大利亚北部有偏北(南)风异常, 将暖池的热量往赤道输送, 使得赤道对流增强(减弱), 产生异常上升(下沉)运动汇入Hadley环流上升支, 增强(减弱)的Hadley环流导致下沉主体偏北(南), 促使副高脊线偏北(南), 从西北太平洋(孟加拉湾)往华南地区(江淮到日本南部)输送水汽增强, 所以华南(江淮到日本南部)夏季降水偏多。      

Isotopic analysis to quantify the role of the Indian monsoon on water resources of selected river basins in the Himalayas

Western disturbances (WDs) and Indian summer monsoon (ISM) led precipitation play a central role in the Himalayan water budget. Estimating their contributions to water resource is although a challenging but essential for hydrologic understanding and effective water resource management. In this study, we used stable water isotope data of precipitation and surface waters to estimate the contribution of ISM and WDs to the water resources in three mountainous river basins - Indus, Bhagirathi and Teesta river basins of western, central and Eastern Himalayas. The study reveals distinct seasonality in isotope characteristics of precipitation and surface waters in each river basin is due to changes in moisture source, hydrometeorology and relief. Despite steady spatial variance in the slope and intercept of regression lines from the Teesta to Indus and the Bhagirathi river basins, the slope and intercept are close to the global meteoric water line and reported local meteoric water line of other regions in the Himalayas and the Tibetan Plateau. The two-component end-member mixing method using d-excess as tracer were used to estimate the contribution from ISM and WD led precipitation to surface water in aforementioned river basins. The results suggest that the influence of the ISM on the water resources is high (>72% to annual river flow) in Teesta river basin (eastern Himalayas), while as the WDs led precipitation is dominantly contributing (>70% average annual river flow) to the surface waters in the Indus river basin (western Himalayas). The contribution of ISM and WD led precipitation in Bhagirathi river basin is 60% and 40%, respectively. The findings demonstrate that the unusual changes in the ISM and WD moisture dynamics have the potential to affect the economy and food security of the region, which is dependent on the availability of water resources. The obtained results are of assistance to policy makers/mangers to make use of the information for better understanding hydrologic response amid unusual behaviour of the dual monsoon system over the region.     

North Atlantic climate impact on early late‐glacial climate oscillations in the south‐eastern Alps inferred from a multi‐proxy lake sediment record

High‐resolution multi‐proxy analyses of a sediment core section from Lake Jeserzersee (Saissersee) in the piedmont lobe of the Würmian Drau glacier (Carinthia, Austria) reveal pronounced climatic oscillations during the early late glacial (ca. 18.5–16.0k cal a BP). Diatom‐inferred epilimnetic summer water temperatures show a close correspondence with temperature reconstructions from the adjacent Lake Längsee record and, on a hemispheric scale, with fluctuations of ice‐rafted debris in the North Atlantic. This suggests that North Atlantic climate triggered summer climate variability in the Alps during the early late glacial. The expansion of pine (mainly dwarf pine) between ca. 18.5 and 18.1k cal a BP indicates warming during the so‐called ‘Längsee oscillation’. The subsequent stepwise climate deterioration between ca. 18.1 and 17.6k cal a BP culminated in a tripartite cold period between ca. 17.6 and 16.9k cal a BP with diatom‐inferred summer water temperatures 8.5–10 °C below modern values and a shift from wet to dry conditions. This period probably coincides with a major Alpine glacier advance termed the Gschnitz stadial. A warmer interval between ca. 16.9 and 16.4k cal a BP separates this cold phase from a second, shorter and less pronounced cold phase between ca. 16.4 and 16.0k cal a BP, which is thought to correlate with the Clavadel/Senders glacier advance in the Alps. The following temperature increase, coupled with wet (probably snow‐rich) conditions, caused the expansion of birch during the transition period to the late glacial interstadial. Copyright © 2011 John Wiley & Sons, Ltd.     

太谷凤凰山饮用天然矿泉水水质特征及开发前景

太谷凤凰山矿泉水位于在建的太谷酎泉寺避暑山在，是锶－重碳酸－钙钠型低矿化度优质饮用天然矿泉水。泉水环境优越，开发利用前景良好。     

EOF迭代方案恢复夏季大气环流场的试验

本文设计了一种恢复夏季大气环流场的EOF(经验正交函数)迭代方案,并利用1951～1984年中国夏季降水距平场和北半球500hPa夏季高度距平场作镢复试验,数值试验效果较好.此项工作表明:利用某些长时间序列的资料通过EOF迭代方案恢复历史时期大气环流是可行的.     

EFFECTS OF ANOMALOUS HEATING ON SUMMER MONSOON OVER ASIA

Based on a zonally non-uniform mean circulation in summer simulated by numerical modelling,perturba-tion heatings ever South Asia and a perturbation cooling over Northwest Australia were incorporated in a nu-merical model to discuss their effects on summer monsoon over Asia and the structure of flow disturbance.     

EFFECTS OF ANOMALOUS HEATING ON SUMMER MONSOON OVER ASIA*

Based on a zonally non-uniform mean circulation in summer simulated by numerical modelling,perturbation heatings ever South Asia and a perturbation cooling over Northwest Australia were incorporated in a numerical model to discuss their effects on summer monsoon over Asia and the structure of flow disturbance.     

澳洲夏季风热源低频变化对北半球冬季风影响的数值研究

采用ｐ－σ混合坐标系的５层原始方程模式研究了与澳洲夏季风低频变化相伴随的对流性低频加热源所激发的大气强迫波和东亚冬季风的关系，结果表明澳洲夏季风低频热源可引起北半球副热带高低层环流、东西向Ｗａｌｋｅｒ环流。经向环流、越赤道气流的低频振荡，其振荡周期、强度与热源的振荡周期、强度有关。结果还进一步表明，澳洲低频热源可激发出扰动的北传，从而引起北半球副热带环流、副热带西风急流的低频振荡，澳洲夏季风活跃后