赤道西太平洋暖池形成原因探讨

通过大洋赤道海域SST场差异及其原因分析,提出赤道大西洋、西印度洋及东太平洋表层水温低的可能原因。较详细地讨论了西太平洋暖池形成原因,这是由于西太暖池决定了Walker环流的产生,而Walker环流的移动和演变同样会对暖池区变化产生重要影响。     

西太平洋暖池海温异常与中国夏季降水的关系

利用1951—2007年NOAA延长重构的海温资料、NCEP/NCAR再分析资料和中国160站降水资料,研究了夏季西太平洋暖池海温的年际变化特征及其与中国夏季降水的关系。结果表明,夏季西太平洋暖池海温异常具有明显的年际变化特征;夏季西太平洋暖池海温异常偏高(低)时,亚洲热低压减弱(加强),西太平洋副热带高压加强(减弱)、位置偏西(偏东),850 hPa风场上中国东部地区为偏北(南)风距平,使得东亚夏季风减弱(增强),导致长江中下游地区夏季降水偏多(少)。     

印度洋–太平洋暖池区中尺度涡特征研究

本文利用1993年2月至2016年1月共23年的中尺度涡数据,对印度洋–太平洋暖池区（即印–太暖池区,15°S～15°N,60°E～170°W）中尺度涡的生命周期、振幅和半径等属性特征以及生命周期内各参数的演变特征进行了统计分析,并研究了印–太暖池区中尺度涡生成个数的季节变化规律及与厄尔尼诺循环的关系。结果表明：印–太暖池区大部分中尺度涡存在生命周期短、非线性、向西移动的特征;气旋涡与反气旋涡各参数的统计特征及其在生命周期内的变化趋势较为相似;印–太暖池区中尺度涡生成个数不具有明显的季节变化,并且会受到厄尔尼诺–南方涛动事件的影响。     

西太平洋暖池区沉积物源示踪研究进展

从沉积物中提取示踪指标是研究西太平洋暖池区古环境和古气候演化的有效途径之一,而准确识别沉积物的源区是其中的关键。目前已通过不同的物源示踪指标,如黏土矿物、石英单矿物、常量元素、稀土元素以及碎屑组分的放射性成因Sr-Nd同位素等,对西太平洋暖池北部和西部第四纪以来的沉积物来源进行了研究,结果表明暖池区沉积物主要来源于亚洲大陆和火山岛弧,部分来源于澳大利亚和/或新几内亚。本文系统归纳和总结了上述示踪指标在西太平洋暖池区的物源研究进展和成果,以及研究中存在的问题,并对西太平洋暖池沉积物源研究提出了几点建议。     

印度洋-太平洋暖池的变异研究

为了研究在何种时间尺度上定义研究印度洋-太平洋暖池（简称印-太暖池）更有意义, 本文中应用功率谱等统计学方法, 对印-太暖池的季节、年际及年代际变化特征进行了分析.结果表明, 印-太暖池、东印度洋暖池（简称东印暖池）在季节变化上表现为单峰结构, 而西太平洋暖池（简称西太暖池）则为双峰结构; 在年际变化上印-太暖池和西太暖池表现出很强的3-6年变化周期, 东印暖池则存在准两年的振荡周期; 印-太暖池还存在10年以上的年代际周期振荡, 特别是70年代中后期的年代际突变明显, 而东印暖池的这种变化更为明显.由此可知印-太暖池的年代际变化与东印暖池、西太暖池年代际变化较为相似, 季节和年际变化颇为不同, 所以, 在研究年代际尺度的问题上, 定义并研究印-太暖池的意义更大, 而在研究年际、季节尺度上的问题时东印暖池、西太暖池应分而视之.     

Elimination of Swimming Pool Water Disinfection By‐products with Advanced Oxidation Processes (AOPs)

Ozonation is a treatment step which was first applied in the 1960s in pool water treatment for disinfection as well as for oxidation of pool water contaminants. Contact time between ozone and pool water was identified to be of significance with an increased elimination efficiency regarding chloramines, trihalogenmethane formation potential and the permanganate index for longer reaction times. Oxidation via OH radicals might be the dominating pathway. In this study ozonation was compared with the ozone based advanced oxidation processes ozone/UV and ozone/hydrogen peroxide regarding the elimination efficiency of both disinfection by‐products (DBPs) and DBP precursors. It was observed that AOPs in comparison to ozonation showed an increased elimination efficiency regarding total organic carbon (TOC), the organically bound halogens adsorbable on activated carbon (AOX) and AOX formation potential. A contact time of 3 minutes between pool water and oxidant turned out to be practically sufficient. Just for the trihalomethane (THM) formation potential ozonation showed a slight advantage compared to the AOPs because ozonation is a highly selective oxidant and OH radical reactions are known to produce small reactive molecules which are easier transformed to THMs. Combination of membrane filtration and AOPs resulted in an elimination of 10 to 90 % of the DBPs and their precursors. The ozone/hydrogen peroxide process is suggested for pool water treatment because of the higher elimination rates compared to ozonation and of economic reasons compared to the ozone/UV process.     

赤道太平洋纬向风和流异常与西太平洋暖池纬向运移

基于SODA再分析资料和TAO资料,利用EOF和统计分析等方法,分别研究了赤道太平洋海面纬向风应力异常和赤道太平洋上层纬向流异常的时空特征及其对西太平洋暖池纬向运移的影响。结果显示,赤道太平洋海面纬向风应力距平场第一模态具有2—5年的年际变化特征,其时空分布呈东、西向的反位相变化;而赤道太平洋上层纬向流距平场的第一模态则为1—2年的年和年际变化,且整个研究区域位相统一。纬向风应力和纬向流异常变化最显著的区域都在赤道中太平洋。相关分析显示,赤道中太平洋海面纬向风应力异常和赤道西太平洋上层纬向流异常分别对西太平洋暖池纬向运移有约2个月和4—6个月的超前影响,是暖池纬向运移的两个重要动力因素。回归分析表明,赤道中太平洋海面纬向风应力异常和赤道西太平洋上层纬向流异常对西太平洋暖池纬向运移有很好的预报意义。     

南海暖水的季节变化特征及数值模拟

根据Ｌｅｖｉｔｕｓ资料,对具有立体结构的南海暖水给出了定义,分析发现：南海暖水的季节变化过程可分为发展、维持、退缩和消失４个阶段;就气候平均而言,南海暖水在季节变化中始终保持西北部浅、东南部深的特点;南海暖水的深度与同期温跃层上界的深度在空间分布特征与季节变化趋势上都基本类似。采用“ｉｎｔｅｒｍｅｄｉａｔｅ”模式模拟了南海暖水的范围和厚度,结果表明发展阶段的南海暖水范围和厚度的增长主要是因为南海地     

赤道西太平洋暖池区更新世以来的生源沉积物沉积特征及其古海洋学意义

赤道西太平洋暖池区中部柱状样MD972140中钙质超微化石氧同位素记录和生物地层学的研究为该柱提供了可靠的年龄框架。氧同位素记录与生源和非生源组分的对比表明，粗组分和碳酸钙含量变化表现为冰期降低，间冰期升高，类似于大西洋型旋回，而蛋白石和非生源组分却与之相反。更新世以来粗组分和碳酸钙含量的变化总体上是由高到低，而蛋白石和非生源组分含量的变化是由低到高，反映了陆源物质输入量和表层水生产力的增加。由此可见，碳酸钙和蛋白石含量的变化主要受到钙质和硅质生物生产力以及陆源物质输入量的控制。氧同位素7期以来，蛋白石含量和硅质微体化石丰度在冰期升高及在间冰期降低的变化反映了表层水生产力的波动和硅质溶解作用的强弱。     

Geometric adjustment of pools to changes in slope and discharge: a flume experiment

To characterize the factors controlling pool shape, 30 different forced pools were created utilizing a 50% triangular constriction in a 0.5-m wide, 6-m long recirculating flume. Pools were scoured from an initial plane bed of sand with a d₅₀ of 0.25 mm. Pool depth and length were measured and used as dependent variables in least-squares, multiple-regression analyses. Discharge, channel-bed gradient and energy slope were the independent variables. Additional linear-regression analyses were conducted with either pool depth or length and stream power. Results indicate that both pool depth and length are primarily a function of discharge. Channel-bed and energy slopes are also significantly related to pool length but are not significantly related to pool depth. Stream power is significantly related to both pool depth and length, but R² values for pool depth versus discharge indicate stronger relations than those between pool depth and stream power. Observations on the type of geometric adjustment indicate that pools may minimize their rate of energy expenditure primarily through elongation. In contrast, pool depth appears to be more sensitive to the characteristics of the constrictions that create the forced pools. The results suggest that many field studies may suffer from cross-correlation problems. In particular, channel erodibility may exert a more dominant influence on pool geometry than hydraulic controls in many constriction-influenced channels.