夏季副热带西部模态水异常与我国秋、冬季气温年际变化的关系

利用合成、回归等方法分析了夏季副热带西部模态水(简称STMW)异常与我国秋、冬季气温年际变化的联系,发现:1)秋、冬季东亚—太平洋地区的大气环流异常对我国的气温变化起了重要作用,夏季STMW异常通过东亚—太平洋地区的大气环流异常进而与我国秋、冬季的气温变化联系在一起。2)夏季ST-MW正(负)异常时,同年秋季我国西北、东北和江淮地区的气温异常偏低(偏高);冬季时,东北、西北地区气温偏高(低)。3)这种联系主要是通过东亚—太平洋地区大气环流的典型分布实现的:夏季STMW异常偏强(弱)时,同年秋季与黑潮附近的冷(暖)海温相对应,西北太平洋上空大气环流出现负(正)的高度距平,气旋性(反气旋性)环流西侧的偏北(南)气流引导(阻碍)东亚大陆中高纬冷空气南下,同时东欧地区的高压(低压)向东南方向伸展,对我国西北地区秋季冷空气的活动起到了增幅(削弱)作用,我国东北、西北和江淮大部分地区的冷空气活动偏强,气温普遍偏低(高)。黑潮区附近的冷(暖)海温持续热力作用下,海洋不断得到(失去)热量,积累到冬季,促使黑潮区域的海表面温度(SST)逐渐向正(负)异常转变。冬季的大气环流场也对应发生调整:西北太平洋上空出现显著的高压(低压)异常,反气旋(气旋)西侧的偏南(北)气流减弱(加强)了我国东北地区的冷空气强度,气温偏高(低);亚洲中纬度地区受低压(高压)距平控制,我国西北地区的冷空气活动较弱(强),气温偏高。     

Large‐scale climatic influences on precipitation and discharge for a British river basin

This article aims to identify the large‐scale climate variables that yield significant statistical relationships with precipitation and discharge for a British river basin (Dyfi). Ranked correlation analysis was performed between gridded ERA‐40 atmospheric data and Dyfi precipitation and discharge for individual months. Precipitation and discharge demonstrate significant negative correlation with mean sea level pressure (MSLP). Strongest MSLP correlation areas move from north of Britain in winter to central Britain in summer; this shift is associated with a displacement of geopotential (Z) and zonal wind (U). Movement of significant correlation regions (not captured by the North Atlantic Oscillation Index) highlights the dynamic nature of precipitation and river flow generating weather systems throughout the year. Existence of strong significant correlation shows potential for exploiting large‐scale climate variables in forecasting precipitation and river flow in Britain. Copyright © 2010 John Wiley & Sons, Ltd.     

我国东部夏季降水百年雨型的多时间尺度变化特征研究

本文用1900-1950年的我国实测的与内插的降水、气温资料，结合近代先进的统计方法对立了1900-1950年我国东部夏季降水雨型序列，并将其与已有的近48年（1951-1998年）的夏季雨型序列相衔接，进而研究了近百年我国夏季雨带的演变规律及其与ENSO的关系，此外，还研究了百年夏季雨型与大气活动中心在基本态时间尺度上的关系，研究了北太平洋涛动和我国夏季降水的关系。     

Collision tectonics in the New Hebrides arc (Vanuatu)

Abstract The New Hebrides island arc in Vanuatu has been significantly modified by collision with several major submarine ridges and plateaux. Bathymetric sections taken at intervals along the arc, perpendicular to the trench, show that prior to collision at 3 Ma the morphology was typical of modern intraoceanic island arcs. Collision has caused uplift of the trench and forearc (up to 6000 m), subsidence around the arc volcanic edifices (up to 2500 m), forming a large intra-arc basin and uplift of the arc-backarc transition (up to 2000 m). In the transition zone between collisional and non-collisional sections of the arc, subsidence occurs in the forearc and uplift occurs around the arc volcanoes. Many of these characteristics are typical of collisions in other Western Pacific island arcs such as the Tonga–Kermadec and Izu–Bonin arcs. The pattern of uplift and subsidence has important implications for the tectonic history of the New Hebrides system. The morphology of the arc shows that collision of the West Torres Massif probably accounts for at least half the uplift. Arrival at 0.7 Ma of the West Torres Massif in the trench may have caused the slowing of subduction in the entire northern half of the arc and not just in the central segment as previously suggested. Re-equilibration of the arc following collision probably masks any evidence of collision prior to 3 Ma. For example, the Efate re-entrant, a large indentation in the arc immediately to the south of the collision zone, probably originated as a result of erosion during collision followed by subsidence after collision. The Vanuatu collision shows that the subduction of seamounts and ridges in an intraoceanic arc temporarily changes the arc morphology, allowing the development of angular unconformities and changing the pattern of sedimentation. This provides information which can be used to facilitate recognition of these events in ancient arc-related sequences.     

Tephrochronology of the Kamchatka–Kurile and Aleutian arcs: evidence for volcanic episodicity

Volcanic ash layers in North Pacific deep-sea sediment provide a record of episodic explosive volcanism in the Kamchatka–Kurile and Aleutian arcs over the past five million years. We counted 450 ash layers, determined layer thickness and cumulative ash thickness to quantify the flux of ash with time. We use this record to investigate the eruptive history of these arcs, test the reliability of the marine ash record, and inquire into the regional episodicity of North Pacific explosive volcanic history. Episodes of explosive volcanism occurred at approximately 0.2–0.5, 0.7–0.9, 1.5–1.7, and 2.5–2.65 Ma in the Kamchatka arc and 0.15–0.4, 1.7–1.8, 2.55–2.65, and at 3.0–3.1 Ma in the eastern Aleutian arc. These generally coeval eruptive episodes suggest that the pulses in explosive volcanism in the North Pacific enumerated here and recognized by others are regionally episodic over a wide portion of the Pacific rim and not just a response to local volcanogenic processes.     

Property Regime or Development Policy? Explaining Growth in the U.S. Pacific Groundfish Fishery

Researchers often blame problems in fisheries on the property regime under which a fishery is practiced. Depending on their perspective, researchers locate the cause of problems in either common property or open access regimes. However, because these approaches rely on the assumption of the “economically rational individual,” they obfuscate the specific cultural, political, and economic practices that shape resource use. Analysis of the U.S. Pacific groundfish fishery shows that growth and subsequent problems in this fishery are the result of a state‐led fisheries development program implemented through a series of national, regional, and local policies designed to extend sovereign control to include ocean territory. These policies both created a climate of fisheries development and provided the means by which the fishery could grow. This analysis highlights the need to examine historic and geographic specificity to explain resource use, rather than relying upon generalized models that posit a deterministic relationship between property regimes and socioenvironmental outcomes.     

罕见的“强烈震群”活动

本文介绍了全世界范围内的“强烈震群”的地区分布、活动频率和强度等特征，并指出“强烈震群”主要分布在太平洋西半部的岛弧－海沟地带，这些“强烈震群”是依据近百年来的现代地震仪观测数据获得的。     

高原季风的年代际振荡及其原因探讨

一、高原季风的形成演化史高原季风是高原对大气的冷热源作用冬夏相反，从而引起的对流层中、低层冬季为反气旋环流，夏季为气旋性环流的总称。在青藏高原的隆升过程中，到渐新世初（约37Ma．B．P．）其水平尺度开始大于斜压大气地转适应的临界尺度’“，高原季风开始出现“’，全球气候经历了一次大转型，从以纬向分布为特征的准天文气候开始转向季风气候。值得提出的是，在早第三纪（如始新世），陆海分布已基本上是现代格局，海陆季风体系（东南季风、西南季风）应该已经形成，然而东亚、南亚地区非常干燥，为什么当时没有季风雨相伴呢…     

吉林省地体构造的基本特征

吉林省地体构造的一个显著特征是在早古生代以前，伊舒断裂两侧分属两个不同的大地构造单元，西侧的构造环境与华北大陆板块北缘相似，为受古蒙古洋作用的早生代活动陆缘，东侧为长白山一张广才岭地体添加带（也称联合地体（省内包括吉林－延边古生代增生褶皱带及辽吉台块。其中辽吉台块于新元古代到早寒纪位于赤道附的，以后沿巨型拆离面逐渐北移，于二叠纪末沿辉发河－古洞河拼贴带，与吉林一延边古生代陆缘增生褶皱带拼贴到一起。