Indian Ocean temperature dipole and SSTA in the equatorial Pacific Ocean

The observed sea surface temperature (SST) data of recent 100 years are analyzed and the existence of the Indian Ocean temperature dipole in the equatorial region is exposed further. It is very clear that the amplitude of the positive phase (higher SST in the west and lower SST in the east than normal) is larger than that of the negative phase (higher SST in the east and lower SST in the west). The dipole is stronger in September-November and weaker in January-April than in other months and it also appears obviously inter-annual and inter-decadal variations. Although the Indian Ocean dipole in the individual year seems to be independent of ENSO in the equatorial Pacific Ocean, in general, the Indian Ocean dipole has obviously negative correlation with the Pacific Ocean dipole (similar to the inverse phase of ENSO mode). The atmospheric zonal (Walker) circulation over the equator is fundamental to relate the two dipoles to each other.     

Interdecadal variability in the tropical Indian Ocean and its dynamic explanation

Interdecadal variability in the tropical Indian Ocean has been analyzed based on the long-term climatic observational data. Case study showed that strong interannual signals formed at the surface can penetrate the depth of seasonal thermocline, where the anomalies last a couple of years. Artificial time series based on damping with exponential decay of selected strong events agree well with the detected interdecadal variability in the tropical Indian Ocean. A possible dynamic explanation for interdecadal variability in the tropical Indian Ocean was proposed that irregular interannual signals can lead to a slowly evolving climatic background with the interdecadal time scale through damping of the memory about anomalies in the seasonal thermocline.     

热带印度洋海面温度与高度的相关性分析

基于海面温度与海面高度异常的月均数据,采用EOF、SVD和功率谱分析等方法,对热带印度洋海面温度与海面高度进行特征分析,研究两者在时空结构上的相关性。利用EOF方法分析出海面温度第二模态与海面高度第一模态的空间结构类似,呈现偶极型。相关分析与功率谱表明,两模态的时间序列存在滞后相关和类似的周期结构。SVD结果显示,第一耦合模态的相关系数达0.7左右,且左右场的空间形态呈现东西反相。这表明,海面高度偶极型与海面温度的单极型和偶极型存在着相关。同时,海面高度指数也表现与偶极子指数类似的结构特征。针对上述诊断分析事实特征,对海面温度和海面高度偶极子形成的物理机制进行了初步分析,总结了前人所做的一些工作,指出其中可能的影响因素。     

热带印度洋偶极子区域海表面温度特征与海流相关性分析

为了研究热带印度洋偶极子(IOD)爆发年其耦合作用迅速消亡是否由海流异常引起,利用1958—2007年热带印度洋月均海表面温度(SST)和海流数据,分析IOD的主要特征,并探讨IOD与ENSO和海流异常之间的相关关系。通过对印度洋偶极子指数(DMI)及其经Hilber-t Huang变换后得到的固有模态函数(IMF)与南方涛动指数(SOI)的相关性分析,指出IOD与ENSO之间可能存在相关性,其中,表现出准2a周期振荡的IMF-3与ENSO相关性最好。通过对IOD爆发年DMI的进一步分析,证实IOD具有季节锁相的重要特征,并探讨该季节变化与海流异常的相关关系。结果表明,海流异常在热带印度洋SST的耦合振荡中起重要作用,但是它可能不是引起IOD迅速消亡的原因。     

Circulation in the western tropical Pacific Ocean and its seasonal variation

An assimilation data set based on the GFDL MOM3 model and the NODC XBT data set is used to examine the circulation in the western tropical Pacific and its seasonal variations. The assimilated and observed velocities and transports of the mean circulation agree well. Transports of the North Equatorial Current (NEC), Mindanao Current (MC), North Equatorial Countercurrent (NECC) west of 140°E and Kuroshio origin estimated with the assimilation data display the seasonal cycles, roughly strong in boreal spring and weak in autumn, with a little phase difference.The NECC transport also has a semi-annual fluctuation resuiting from the phase lag between seasonal cycles of two tropical gyres' recirculations. Strong in summer during the southeast monsoon period, the seasonal cycle of the Indonesian throughfiow (ITF) is somewhat different from those of its upstreams, the MC and New Guinea Coastal Current (NGCC), implying the monsoon's impact on it.     

热带印度洋海温与海表面高度相关关系分析

为了研究热带印度洋偶极子(IOD)与海平面异常之间的相关性,采用经验正交函数分析方法(EOF)及Hilbert-Huang变换等统计方法,分析热带印度洋的海表面温度(SST)与海平面高度异常(SLA)的相关关系。通过对热带印度洋偶极子指数(DMI)与南方涛动指数(SOI)和SLA的相关性分析,得出IOD与El Nio-Southern Oscillation(ENSO)之间可能存在一定相关关系,此外,IOD与海平面变化有很好的相关性。通过对IOD爆发年的DMI以及海平面变化的分析,证实IOD具有季节锁相的重要特征,并探讨了该季节变化与海平面变化的相关关系。结果表明,IOD事件与海平面的变化这两者之间存在很强的一致性。     

热带海温对纵向岭谷区5月降水年际变化的影响研究

 利用主成分分析和典型相关分析方法,研究了纵向岭谷区76个站点5月份降水场与其前期(12~4月)和同期(5月份)热带海温距平场之间的相关关系.其中,资料选用了1961~2001年共41 a的数据资料.研究结果表明,纵向岭谷区5月降水与热带海温距平场以同期相关为最好,而前期热带海温距平场除12月、3月和4月外,其它月份即1月、2月均有很好的相关.通过对热带海温距平场及降水场典型特征向量的分布作分析,太平洋暖池区热带海温与纵向岭谷区5月降水有正相关关系,赤道东太平洋海温与纵向岭谷区5月降水有负相关关系.当太平洋Walker环流增强时,纵向岭谷区5月降水增多;当Walker环流减弱时,纵向岭谷区5月降水减少.     

2003 vs 2002: A large amplitude wintertime temperature anomaly reversion event and its anomalous atmospheric circulation

It is revealed that there happened a large amplitude wintertime temperature anomaly reversion event (LTAR) in Northern Hemisphere high latitude regions and South Australia for the year 2003 versus 2002, with the most notable change in Eurasia, eastern North America, North Pacific, and South Australia. The accompanying atmospheric general circulation anomalies are analyzed and the dominant changes in the circulation are found out. The anomalous cyclonic eddies over the north Pacific and the anomalous anticyclonic eddies over North Europe that cooperate each other are mostly linked with the event. Both anomalous eddy systems are connected with the remote teleconnection patterns respectively. The research also suggests the existence of a cross-equator teleconnection pattern, namely, the Northern Pacific-Western Pacific-Australia teleconnection pattern (NPWPA). It is not only related to LTAR, but also associated with the temperature transition from cold episode to warm episode in the year 2003 versus 2002 during December-January-February.     

Further exploration on causes of temperature anomalies associated with the abnormal northern annular mode

This article concerns the temperature anomalies during the high index phase of the northern annual mode for the wintertime from January to March, The response of the zonal and meridional winds and the temperature advection caused by the anomalous horizontal wind are investigated. The results show that both the zonal and meridional winds experience strong anomalies and the temperature advection induced by both the anomalous zonal and meridional winds is responsible for the temperature anomalies associated with the high index northern annual mode. The temperature advection induced by the anomalous zonal wind contributes dominantly to the cooling in the Atlantic and the Bering Sea while the temperature advection induced by the anomalous merional wind contributes dominantly the warming in the United States of America and the cooling in southern Europe and Canada. The superposed influences caused the obvious warming in north Eurasia.     

热带太平洋海平面年际和年代际变化研究进展

回顾热带太平洋对海平面长期趋势有重要影响的海平面年际和年代际变化的相关研究,总结包括近期提出的中部型厄尔尼诺在内的2种类型厄尔尼诺对热带太平洋海平面年际变化的影响,揭示了热带太平洋海平面年代际变化与信风年代际变化之间的紧密联系。指出赤道信风的增强对近期热带太平洋海平面变化格局的形成有决定性作用,厄尔尼诺强度的减弱对这种格局有贡献,而拉尼娜的影响有待深入研究。研究资料的局限性导致年代际变化的定量研究成果较少,在研究海平面年际和年代际变化时应用的热通量评估模型有待改进。     

Relationship between the tropical cyclone genesis over the Northwest Pacific and the sea surface temperature anomalies

Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.     

Relationship between the tropical cyclone genesis over the Northwest Pacific and the sea surface temperature anomalies

Using the tropical cyclone (TC) data derived from the Joint Typhoon Warning Center (JTWC) and the sea surface temperature data derived from the Joint Environmental Data Analysis Center (JEDAC) at the Scripps Institute of Oceanography from January 1955 to December 2000, we analyzed the relationship between the TC genesis over the Northwest Pacific (NWP) and the sea surface temperature anomalies (SSTA) over the Pacific basin. A long-term trend indicated that the highest frequency of monthly TC genesis appeared earlier and the annual genesis sum increased gradually during the last half century with some oscillations. No significant synchronous correlation was found between the NWP TC events and the SSTA over the Pacific basin, while the annual sum of TC genesis was closely related with the SSTA averaged from the first three months (January, February and March) of the year in the equatorial western and eastern Pacific and over mid-high latitudes of the North Pacific. The results implied that there are an interannual El Nio SSTA mode in the equatorial western and eastern Pacific and an interdecadal SSTA mode in the northern Pacific, which affected the TC genesis. A regression analysis between the first three-month SSTA and the annual TC sum based on two time scales was conducted. The correlation coefficient between simulated and observed TC sums reached a high value of 0.77.     

Effects of zonal perturbations of sea surface temperature on tropical equilibrium states: A cloud-resolving modeling study

The effects of zonal perturbations of sea surface temperature (SST) on tropical equilibrium states are investigated based on a series of two-dimensional cloud-resolving simulations with imposed zero vertical velocity, constant zonal wind, and a zonal model domain of 768 km. Four experiments with zonal SST perturbations of wavenumbers 1 (C1), 2 (C2), 4 (C3), and 8 (C4) are compared to a control experiment with zonally uniform SST (C0). The 40-day integrations show that the temperatures reach quasi-equilibrium states with distinct differences. C1 and C2 produce warmer equilibrium states whereas C3 and C4 generate colder equilibrium states than C0 does. The heat budgets in the five experiments are analyzed. Compared to C0, less IR cooling over smaller clear-sky regions in C1 and more condensational heating in C2 are responsible for warmer equilibrium states. A reduced condensational heating leads to the cold equilibrium state in C3. The interaction between convective systems in C4 causes a decrease of condensational heating, which accounts for the cold equilibrium state.     

Signal propagations and linkages of subsurface temperature anomalies in the tropical Pacific and Indian Ocean

The propagation characteristics of signals along different zonal-time profiles are analyzed using surface and subsurface temperature anomalies over the tropical Pacific and Indian oceans. Analyses show that there are intrinsic relationships between El Nio events in the eastern equatorial Pacific and dipole events in the equatorial Indian Ocean. In the region of tropical North Pacific between the equator and 16°N, there is a circle of propagation of subsurface temperature anomalies. El Nio events only happen when the warm subsurface signals reach the eastern equatorial Pacific. Dipole events are characterized when a warm subsurface signal travels along off-equatorial Indian Ocean to the western boundary. From these analyses, we believe that subsurface temperature anomalies can be considered to be the oceanographic early signal to forecast El Nio events in Pacific Ocean and dipole events in Indian Ocean, respectively.     

热带太平洋和印度洋海温对中国雨带类型的影响

 根据1950~1999年的海温距平和中国夏季(6~8月)雨带分布类型资料,分析了各雨型与前期及同期热带太平洋和印度洋(21°S~21°N,29°E~81°W)海温异常的相关关系.分析表明,不同雨带类型和所对应同期及前期太平洋和印度洋海温有很好的相关关系.     

温度对电极电位精确度影响及其校正

以氯化钠溶液电解中的氯电极为例 ,论述了氯电极的标准电位 φ 怎样随温度变化 ,参比电极和标准氢电极电位又是怎样变化 ,从而引出“等温温度系数”和“温差温度系数”两个基本概念 ,并导出其计算公式     

台风季中国热带气旋降水的典型模态及显著影响因子

本文利用客观分离的热带气旋降水的台站资料,运用经验正交分解法分析了台风季中国热带气旋降水的前两个主要典型模态及其与同期西北太平洋热带气旋源地路径的关系,以及与海表面温度和500 hPa环流场的关系.结果表明:热带气旋降水第1模态表现为以华南西南为正中心而华东为负中心的偶极子振荡型,此模态出现于赤道中东太平洋海表面温度一次冷异常过程的鼎盛时期,对应的西北太平洋500 hPa环流异常主要表现为低纬中西太平洋海域的东风异常以及中国区域北高南低的环流异常,在这样的环流异常配置下,热带气旋源地显著偏西,西行路径显著偏多,而北折路径较为偏少.热带气旋降水第2模态表现为以华东及海南南端区域为正中心的中国大部地区的一致同步型,此模态出现于赤道中东太平洋海表面温度一次冷异常逐渐减弱并向暖异常过渡的相位变化时期,对应的西北太平洋500 hPa环流异常各月差异较大,7、9月份的环流异常配置使热带气旋路径偏南更易侵袭我国海南等南端区域,而8月的环流异常配置导致热带气旋源地偏北,中国东南近海热带气旋生成频数显著偏多,且其路径更易北折影响华东地区.     

南极-艾肯盆地Th异常的富集特征和机理

遥感探测表明月表Th元素分布存在全球不均衡性,形成分别以雨海-风暴洋和南极-艾肯（SPA）盆地为中心的Th异常区.研究认为雨海-风暴洋的Th主要来源于对其下覆KREEP物质的开掘,但对SPA盆地的Th来源有各种不同的认识.本文通过对SPA盆地的地形、盆地构造、撞击坑分布、火山作用和地球化学特征的分析,以及对Th富集机理的探讨,认为SPA盆地内Th更可能来源于撞击作用对富Th下月壳物质的开掘;Th的弧形富集特征与盆地构造有很大相关性,并可能受到Apollo盆地形成的影响.     

高温及冷却方式对花岗岩的影响规律分析

实际干热岩开采时储层花岗岩会经历高温-水冷冲击耦合过程。将花岗岩加热并分别进行室温冷却及水冷处理,并进行超声波测试、单轴抗压、XRD、电镜扫描等试验来探究高温及冷却方式对花岗岩损伤特征的影响。发现高温导致花岗岩体积增大、质量降低、纵波波速降低、弹性模量降低、抗压强度减弱等,500℃-700℃下花岗岩的物理力学性质劣化迅速;微观上高温导致微裂缝的生成,水冷处理促进微裂缝的开裂和传播;宏观上水冷花岗岩的物理力学性能始终较低且塑性及延展性特征明显较高。     

The relationship between sea surface temperature anomaly and wind energy input in the Pacific Ocean

The relationship between sea surface temperature anomaly (SSTA) and wind energy input in the Pacific Ocean over the period of 1949–2003 is studied by using daily-mean NOAA/NCEP wind stress and monthly mean Reynolds SST data. The results indicate the strong negative correlation between SSTA and local wind energy input to surface waves in most of the domain at low and middle latitudes. The SST is low (high) during the years with more (less) wind energy input. The correlation coefficients are high in the central and eastern tropical Pacific and the central midlatitude North Pacific at the decadal scale, and in the central tropical Pacific at the interannual scale. Vertical mixing processes in the upper ocean are closely associated with wind energy input, indicating that wind energy input may play an important role in interannual and decadal variability in the Pacific Ocean via regulating vertical mixing.