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71.
In the context of a model of tropical cyclone intensity based on an improved meso-scaleatmospheric model, numerical simulation is performed of the track and intensity variation oftropical cyclones (TC) arising from sea surface temperature (SST) variation over a specified searegion. Evidence suggests that the model is capable of modeling quite welt the track and intensityof TC: SST variation leads to an abrupt change in the cyclone intensity: the response of thecyclone to the abrupt SST change lasts 8—12 h. 相似文献
72.
NUMERICAL EXPERIMENT OF IMPACT OF SEA SURFACE TEMPERATURE IN SOUTH CHINA SEA AND WARM POOL/WEST PACIFIC ON EAST ASIAN SUMMER MONSOON 总被引:1,自引:0,他引:1
By using the NCAR CCM1 model, we have designed six sensitive experiments, which areincreased and decreased SST (sea surface temperature) by 1℃ each in the SCS (South China Sea)and in the West Pacific warm pool, increased and decreased SST by 1℃ in the warm pool withincreased SST by 1℃ in the SCS. All experiments are integrated from April to July. Comparingwith the control experiment, we have analyzed the anomalies of the wind field at the upper andlower layers, the anomalies of the seasonal variability of the monsoon and precipitation for eachexperiment. In the result, we have found that the SST anomaly (SSTA) in the SCS greatly affectsthe seasonal variability of the SCS monsoon and precipitation in China, especially during the coldperiod of SST in the SCS. The impact of SSTA in the warm pool on SCS monsoon is also found.but is weak as compared to the effect of SST anomaly in the SCS. Besides, its impact on rainfall inChina is uncertain. 相似文献
73.
对长江坝区汛期降水的气候背景进行了分析后指出:坝区汛期降水异常与EAA相关链,特别是东亚这一段遥相关型有明显联系,进而探讨了它与前期北太平洋海水温度的关系。 相似文献
74.
75.
It is well established that sea surface temperature (SST) plays a significant role in the hydrologic cycle in which precipitation is the most important part. In this study, the influence of SST on Indian subdivisional monthly rainfall is investigated. Both spatial and temporal influences are investigated. The most influencing regions of sea surface are identified for different subdivisions and for different overlapping seasons in the year. The relative importance of SST, land surface temperature (LST) and ocean–land temperature contrast (OLTC) and their variation from subdivision to subdivision and from season to season are also studied. It is observed that LST does not show much similarity with rainfall series, but, in general, OLTC shows relatively higher influence in the pre‐monsoon and early monsoon periods, whereas SST plays a more important role in late‐ and post‐monsoon periods. The influence of OLTC is seen to be mostly confined to the Indian Ocean region, whereas the effect of SST indicates the climatic teleconnection between Indian regional rainfall and climate indices in Pacific and Atlantic Oceans. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
76.
77.
The effect of the wave-induced mixing on the upper ocean temperature in a climate model 总被引:3,自引:1,他引:2
The significant underestimation of sea surface temperature (SST) and the temperature in the upper ocean is one of common problems in present climate models. The influence of the wave-induced mixing on SST and the temperature in the upper ocean was examined based on a global climate model. The results from the model coupled with wave-induced mixing showed a significant improvement in the simulation of SST and the temperature in the upper ocean compared with those of the original model without wave effects. Although there has still a cold bias, the new simulation is much closer to the climatology, especially in the northern ocean and tropical ocean. This study indicates that some important physical processes in the accurate simulation of the ocean may be ignored in present climate models, and the wave-induced mixing is one of those factors. Thus, the wave-induced mixing ( or the effect of surface waves) should be incorporated properly into climate models in order to simulate or forecast the ocean, then climate system, more accurately. 相似文献
78.
海表水温变动对东、黄海鲐鱼栖息地分布的影响 总被引:6,自引:2,他引:4
海表水温(SST)通常是表征鱼类栖息地分布的主要指标。本文根据1999—2007年我国大型灯光围网的鲐鱼生产统计数据,结合海洋遥感获得的SST,分析了渔汛期间鲐鱼栖息地的适宜SST范围,探讨了SST变动情况下鲐鱼栖息地的变化趋势。研究结果表明,东、黄海鲐鱼7—12月的适宜SST范围为15~30℃。根据政府气候变化专门委员会(IPCC)第四份评估报告,本文拟定4种SST上升的情况,即(1)每月平均SST+0.5℃;(2)每月平均SST+1℃;(3)每月平均SST+2℃;(4)每月平均SST+4℃。结果显示,东、黄海鲐鱼的潜在栖息有明显向北移动的趋势,并且栖息地面积逐渐减小。研究认为,全球气候变化引起的SST上升,可能会对近海鲐鱼栖息地造成严重的影响。 相似文献
79.
利用NCEP/NCAR再分析资料和NOAA海温资料,用EOF、相关分析等方法,分析了1960—2010年500 hPa和100 hPa等压面上北半球后冬(2月)极涡面积和前春(4月)北太平洋(20~60 °N,120 °E~120 °W)海表温度(SST)的变化特征,揭示了二者的时空联系。结果表明:近50 a来,(1)冬季北半球500 hPa和100 hPa极涡面积整体经历了先扩张后收缩的变化。春季北太平洋SST经历了先降低后升高的变化。其突变时间与500 hPa极涡面积的突变时间相近,均出现在1987年,且与后冬500 hPa大西洋欧洲大陆区(Ⅳ区)极涡面积相关更好。(2)春季北太平洋SST的EOF第一模态空间型表现为PDO,第二模态表现为三极子型,突变分别出现在1980s初期和中期。(3)北太平洋SST与500 hPa Ⅳ区极涡面积相关的空间分布表现为:当前期春季北太平洋中部海温异常偏高(低),南部和北部海温异常偏低(高),使得下一个冬季500 hPa Ⅳ区极涡面积的扩大(缩小),这种空间遥相关型对应着海温的第二模态。北太平洋海温异常以第一模态空间型居多,但是对后冬北半球极涡面积影响大的却是第二模态。(4)当前春北太平洋SST呈第二模态时,对应次年冬季中高纬度对流层温度"上冷下暖",极地东风和绕极西风环流加强,极涡面积偏大。 相似文献
80.
利用观测海温资料和CMIP5模式模拟结果分析西北太平洋(120°E~120°W,20~60°N)海表温度的气候态和年代际变化特征。结果表明,所选22个模式可以较好地模拟出西北太平洋海表温度的气候特征及其年际、年代际变化特征;模式模拟的海表温度总体标准偏差在黑潮延伸体区域最大;绝大多数模式能模拟出海表温度的第一EOF模态;西北太平洋海表温度具有较明显的年代际振荡现象,13/22的模式模拟的海表温度存在明显的年代际振荡,同时海表温度气候态的模拟偏差对其周期振荡模拟的影响较大,尤其在黑潮延伸体区域。 相似文献