1997年北半球大气环流特征及其影响

１９９７年北半球主要环流特征为：５００ｈＰａ西太平洋副热带高压盛夏由弱转强、西伸明显、脊线位置偏北;亚洲中纬度经、纬向环流交替出现,纬向环流盛行,春、秋季经向环流加强,冬、夏季冷空气异常偏弱;盛夏南海季风增强,印度季风偏弱;赤道辐合带偏弱。北半球１００ｈＰａ中低纬度位势高度持续偏高,南亚高压东扩明显;热带海洋出现异常,一次新的厄尔尼诺事件发生,强度大、发展快。在ＥＮＳＯ和大气环流的共同影响下我国天     

春季南方涛动和初夏南海高压对长江中下游地区夏涝的影响

该文揭示了春季南方涛动和初夏（４～６月）南海高压与夏季（６～８月）长江中下游地区洪涝的关系．南方涛动指数（ＳＯＩ）异常偏负和南海高压异常偏强是夏季长江中下游地区发生洪涝的前兆强信号,这两个强信号对长江中下游和江南北部地区夏涝的长期预测有指示性．     

厄尔尼诺与行星运动的联系及其预测

计算了１９５０～２０５０年太阳系各大行星运行轨道及冲日时间,将计算结果与厄尔尼诺年进行比较分析,发现厄尔尼诺事件的发生与行星运动有重要的联系：在１９５０～１９８９年期间,所有的厄尔尼诺事件都发生在四大行星（火、木、土、天王星）冲日时日心黄纬的极值年或极值年的下１年,在其它年份则不发生厄尔尼诺现象。大行星在３月冲日和８月冲日,对厄尔尼诺事件的发生非常有利。从这一事实出发,预测了今后５０ａ厄尔尼诺将要发生的年份。     

1976—1977年及1982—1983年厄尔尼诺事件过程差异的年代际背景

本文根据NMC客观分析资料进行诊断分析,揭示了1976－77年及1982－83年这两次ElNino事件海气相互作用过程中的若干特征。结果表明：70年代末赤道西风异常背景场、SST背景场及其准4年周期振荡均存在年代际变化;SST背景场冷（暖）、80°W-0°E赤道区域850hPa纬向风异常西（东）风以及赤道太平洋SSTA准4年周期振荡东传型（西传型）共同决定了这两次事件的强度与类型的差异,即1976／77年事件为较弱的东部型EINino事件,而1982／83年事件表现为很强的西部型EINino事件。     

埃尔－尼诺年西北太平洋的台风活动

文中统计分析了１９４９～１９９１年西北太平洋近赤道地区（０°～１０°Ｎ，１２５°～１８０°Ｅ）和热带地区（１０°～２５°Ｎ，１２５°～１８０°Ｅ）的台风日数。发现埃尔－尼诺年上述两地区的台风日数明显偏多。因此，冬、春各季该地区的台风日数、可作为该年是否可能发生埃尔－尼诺的一个预报指标。     

The evolution of oceanic and atmospheric anomalies in the northeast Pacific during the El Niño and La Niña events of 1995–2001

From late 1995 through early 2001, three major interannual climate events occurred in the tropical Pacific; the 1995–97 La Niña (LN), 1997–98 El Niño (EN), and 1998–2001 LN. We analyze atmospheric and upper oceanic anomalies in the northeast Pacific (NEP) during these events, and compare them to anomalies both elsewhere in the north and tropical Pacific, and to typical EN and LN anomaly patterns. The atmospheric and oceanic anomalies varied strongly on intraseasonal and interannual scales. During the 1995–97 LN and 1997–98 EN, the Northeast Pacific was dominated by negative SLP and cyclonic wind anomalies, and by upper ocean temperature and sea surface height (SSH) anomalies. The latter were positive along the North American west coast and in the NEP thermal anomaly pool (between Hawaii, Vancouver Island, and Baja California), and negative in the central north Pacific. This atmospheric/oceanic anomaly pattern is typical of EN. An eastward shift in the atmospheric teleconnection from east Asia created EN-like anomalies in the NEP during the 1995–97 LN, well before the 1997–98 EN had begun. The persistence of negative sea-level pressure (SLP) and cyclonic wind anomalies in the NEP during the 1997–98 EN intensified pre-existing upper oceanic anomalies. Atmospheric anomalies were shifted eastward during late 1996–early 1998, leading to a similar onshore shift of oceanic anomalies. This produced exceptionally strong positive upper ocean temperature and SSH anomalies along the west coast during the 1997–98 EN, and explains the unusual coastal occurrences of several species of large pelagic warm-water fishes. The growth and eastward shift of these pre-existing anomalies does not appear to have been linked to tropical Pacific EN anomalies until late 1997, when a clear atmospheric teleconnection between the two regions developed. Prior to this, remote atmospheric impacts on the NEP were primarily from east Asia. As the 1998–2001 LN developed, NEP anomalies began reversing toward the typical LN pattern. This led to predominantly negative SLP and cyclonic wind anomalies in the NEP, and upper ocean temperature and SSH anomalies that were mainly negative along the west coast and positive in the central north Pacific. The persistence of these anomalies into mid-2001, and a number of concurrent biological changes in the NEP, suggest that a decadal climate shift may have occurred in late 1998.During 1995–2001, NEP oceanic anomalies tracked the overlying atmospheric anomalies, as indicated by the maintenance of a characteristic spatial relationship between these anomalies. In particular, wind stress curl and SSH anomalies in the NEP maintained an inverse relationship that strengthened and shifted eastward toward the west coast during late 1996–early 1998. This consistent relationship indicates that anomalous Ekman transport driven by regional atmospheric forcing was an important contributor to temperature and SSH anomalies in the NEP and CCS during the 1997–98 EN. Other studies have shown that coastal propagations originating from the tropical Pacific also may have contributed to coastal NEP anomalies during this EN. Our results indicate that at least some of this coastal anomaly signal may have been generated by regional atmospheric forcing within the NEP.     

地球赤道上空地月距离的4.425a周期与厄尔尼诺、地球自转、海面变化及地裂缝的关系

文中论述了在地球赤道上空,地月距离存在4.425a 的变化周期,是由于月近地点在8.85a的周期性运移中,每到黄径0°和180°(赤道线上)在地球自转的背景下使地月距效果相同所致。而每年的地近日点(1月3日或4日)正置圣诞节过后几天,因此,日、月、地相对运动每隔4.425a 在圣诞节前后三者距离总会达到最近。本文计算了1910～1991年圣诞节前后赤道上空地月距离的变化,发现日、月、地最近时与厄尔尼诺、地球自转、海平面变化,地裂缝等自然现象的发生存在着统计上可以认可的相关性。     

The Continuous Plankton Recorder survey and the North Atlantic Oscillation: Interannual- to Multidecadal-scale patterns of phytoplankton variability in the North Atlantic Ocean

At interannual to multidecadal time scales, much of the oceanographic and climatic variability in the North Atlantic Ocean can be associated with the North Atlantic Oscillation (NAO). While evidence suggests that there is a relationship between the NAO and zooplankton dynamics in the North Atlantic Ocean, the phytoplankton response to NAO-induced changes in the environment is less clear. Time series of monthly mean phytoplankton colour values, as compiled by the Continuous Plankton Recorder (CPR) survey, are analysed to infer relationships between the NAO and phytoplankton dynamics throughout the North Atlantic Ocean. While a few areas display highly significant (p < 0.05) trends in the CPR colour time series during the period 1948–2000, nominally significant (p < 0.20) positive trends are widespread across the basin, particularly on the continental shelves and in a transition zone stretching across the Central North Atlantic. When long-term trends are removed from both the NAO index and CPR colour time series, the correlation between them ceases to be significant. Several hypotheses are proposed to explain the observed variability in the CPR colour and its relationship with climate in the North Atlantic.     

Upper-ocean thermal structure and heat content off the US West Coast during the 1997-1998 El Niño event based on AXBT and satellite altimetry data

During the 1997/1998 El Niño event, extensive oceanic temperature profiles were taken off the coast of California in January and February 1998 using Airborne Expendable Bathythermographs (AXBTs). These AXBT measurements are compared with altimetry-based upper-ocean temperature estimates using TOPEX and ERS satellite altimetry data. The altimetry-based temperature estimates are well correlated with the AXBT data, in particular when combining the two satellite data sets together to form a blended altimeter temperature estimate. Both the AXBT and altimetry data show that the nearshore coastal El Niño signal differed from that further offshore. The AXBT data show that near shore, the warm anomalies extended to much greater depths and had greater amplitude. A time series of the satellite-derived layer-averaged temperatures, averaged separately over the nearshore and offshore halves of the AXBT analysis domain, also shows a larger El Niño signal in the nearshore half. The role of local atmospheric forcing of the coastal oceanic temperature anomalies is analyzed using NCEP reanalysis and coastal upwelling data sets. The forcing terms include Ekman pumping, radiation, surface heat fluxes, precipitation, and alongshore wind stresses that drive coastal upwelling (expressed as a coastal downwelling index, CDI). The temperature forcing from all of the terms except the CDI anomalies are small. The CDI anomalies can explain most of the slowly varying temperature changes that occur near the coast during a two-year period spanning the El Niño event, as well as some of the larger amplitude, rapid (monthly) warming episodes that appear to be part of the El Niño signal. Several distinct rapid warming episodes, however, are not correlated with the CDI anomalies, and therefore we conclude that the nearshore El Niño signal originates from a combination of both a remote oceanic pathway and local atmospheric forcing.