北半球平流层爆发性增温的持续时间与太平洋海温异常的联系

发布时间：2018-04-13 19:15

本文选题：平流层爆发性增温 + 厄尔尼诺　；参考：《兰州大学》2017年博士论文

【摘要】：本文利用NCEP-NCAR再分析资料,ERA-Interim再分析资料,HadISST海温资料,NOAA的大气顶射出长波辐射(OLR)资料,结合WACCM3模式,分析了北半球平流层爆发性增温的持续时间和太平洋海温异常之间的联系。首先分析了平流层爆发性增温出现的前兆。进而分析了热带太平洋海温对平流层爆发性增温的影响。然后分析了热带外海温对平流层爆发性增温的影响。论文还深入探讨了海温通过大气遥相关影响中高纬度大气环流和行星波进而影响平流层爆发性增温的特征和机理。1.首先利用NCEP-NCAR以及ERA-Interim再分析资料,诊断分析了平流层爆发性增温出现前对流层环流的差异,以及不同持续时间的爆发性增温出现后对流层环流的差异。结果表明,平流层爆发性强增温和弱增温的强度和持续时间具有正比关系,但是强增温的强度和持续时间之间的线性关系很强,而弱增温的强度和持续时间的线性关系相对较弱。研究表明弱增温出现前上对流层的位势高度异常类似于正相位的太平洋北美遥相关型,而强增温出现前上对流层的位势高度异常类似于正相位的西太平洋遥相关型;此外,强增温爆发前,行星1波和行星2波的强度都有所增强,而弱增温爆发前,只有行星1波的强度有所增强。持续时间长的平流层爆发性增温出现前伴随着更多正相位的太平洋北美遥相关和西太平洋遥相关。相比持续时间短的强增温,持续时间长的强增温的风速、温度和北半球环状模异常信号下传的高度更低,在下平流层维持的时间更长。2.利用NCEP-NCAR再分析资料,HadISST海温资料,OLR资料,结合WACCM3模式分析了东太平洋厄尔尼诺和中太平洋厄尔尼诺相关的热带太平洋海温变化对北半球冬季平流层爆发性增温持续时间的影响。研究表明,中太平洋厄尔尼诺期间强增温和弱增温的持续时间都要小于东太平洋厄尔尼诺期间强增温和弱增温的持续时间,但是中太平洋厄尔尼诺期间强增温和弱增温的出现频率与东太平洋厄尔尼诺期间强增温和弱增温的频率相比并没有显著差异。分析发现,在东太平洋厄尔尼诺期间高纬度的位势高度常常表现出正相位的太平洋北美遥相关和西太平洋遥相关的特征,但是中太平洋厄尔尼诺期间中高纬度的位势高度表现出负相位的西太平洋遥相关的特征。高纬度上传的行星1波在东太平洋厄尔尼诺期间有所加强而在中太平洋厄尔尼诺期间有所减弱,高纬度上传的行星波通量的增强又进一步导致极涡的减弱,故东太平洋厄尔尼诺期间平流层爆发性增温的持续时间长于中太平洋厄尔尼诺。3.除了研究热带海温对平流层爆发性增温的影响,论文还使用HadISST数据以及NCEP-NCAR再分析资料,结合WACCM3模式,探讨了热带外太平洋海表面温度与冬季北半球平流层爆发性增温之间的联系。研究发现,冬季北太平洋海表面温度的第二主分量(PC2)和平流层爆发性增温的持续时间的相关系数接近于厄尔尼诺和平流层爆发性增温持续时间的相关系数,并且PC2和爆发性增温持续时间的相关系数大于冬季北太平洋海表面温度的第一主分量(PC1)和爆发性增温持续时间的相关系数。本文研究还发现1980年之后,平流层爆发性增温的持续时间的时间序列和PC2的时间序列中存在周期为10-20年的振荡,而且平流层爆发性增温持续时间的年代际振荡和PC2的年代际振荡相一致。当PC2处于正相位时,冬季平流层爆发性增温持续时间更长。当PC2处于负相位时,冬季平流层爆发性增温持续时间更短。虽然PC2海温异常作为热带外海温的异常,主要受到热带外大气环流的驱动,但是WACCM3模式结果表明,PC2海温异常,特别是在副热带西太平洋边界区域的海温异常,对大气具有一定的反馈作用,副热带西太平洋临近区域的海温正异常可以产生更多的对流活动,进而通过遥相关影响中高纬度的环流及行星波,最终对平流层爆发性增温产生一定的影响。4.采用NCEP-NCAR再分析资料和HadISST海温数据研究了太平洋北美遥相关和西太平洋遥相关不同的组合对平流层爆发性增温的持续时间的影响。结果表明当冬季西太平洋遥相关和太平洋北美遥相关都处于正相位时,平流层爆发性增温的持续时间最长,而当西太平洋遥相关和太平洋北美遥相关都处于负相位时,平流层爆发性增温的持续时间最短。另外,这两种组合与热带海温异常与西太平洋海温异常具有密切的联系。本文的创新之处在于,发现了虽然热带外海温变率的第一模态的解释方差较大,但是热带外海温的第二模态对平流层爆发性增温的影响大于第一模态的影响。
[Abstract]:Using the NCEP-NCAR reanalysis data, ERA-Interim reanalysis data and HadISST SST data, NOAA the top of the atmosphere of outgoing longwave radiation (OLR) data, the WACCM3 model, analyzes the relationship between duration of explosive stratosphere of the northern hemisphere warming and SST anomalies in the Pacific Ocean. First analysis of the stratospheric sudden temperature appears. Then by precursor analysis the influence of SST in the tropical Pacific Ocean of stratospheric sudden warming. Then it analyzes the impact of tropical sea temperature of stratospheric sudden warming. The paper also discusses the characteristics and mechanism of.1. SST through influencing atmospheric remote in High Latitude Atmospheric Circulation and planetary waves affect the SSW first by NCEP-NCAR and ERA-Interim reanalysis data diagnosis, analysis of the SSW difference before the tropospheric circulation, and different duration of the explosion The difference after the tropospheric circulation of increasing temperature. The results show that the stratospheric sudden warming and strong weak warming intensity and duration is a direct relationship, but the linear relationship between the high temperature increase the intensity and duration of the strong linear relationship and weak temperature increasing the intensity and duration of the study is relatively weak. Weak increasing Pacific North American teleconnection temperature geopotential height anomalies before the upper troposphere is similar to the Yu Zheng phase, and the strong Western Pacific teleconnection pattern temperature potential before the upper troposphere height anomalies similar to the Yu Zheng phase; in addition, the high temperature increase before the outbreak of the planetary wave 1 and wave intensity have 2 planets enhanced, and weak warming before the outbreak, only the strength of the planetary wave 1 has been enhanced. The long duration of the stratospheric sudden warming appeared with more positive phase of the Pacific North American teleconnection and the Western Pacific. Related. Than the short duration of strong warming, wind speed and long duration of high temperature increase, the lower the temperature and the height of the Northern Hemisphere annular anomaly mode of signal transmission, reanalysis data in the lower stratosphere maintained longer by.2. NCEP-NCAR, HadISST SST, OLR data, analysis of the tropical Pacific SST Variations in East Pacific and El Nino in the Pacific El Nino warming duration of winter in the northern hemisphere stratospheric sudden combined with WACCM3 model. The results show that in the Pacific during El Nino strongly increasing duration of moderate weak warming are less than the eastern Pacific during El Nino strongly increasing duration of moderate weak warming, but in the Pacific during El Nino warming and strong weak growth the temperature and frequency of the East Pacific Ocean during El Nino warming and strong weak warming and no significant difference compared with the frequency analysis showed that in the East The Pacific Ocean during El Nino potential high latitude height is often characterized by the positive phase of the Pacific teleconnection North American teleconnection and the Western Pacific, but the potential of high latitude in the Pacific during El Nino in height shows the characteristics of teleconnections negative phase of the Western Pacific. The high latitude planetary wave 1 upload strengthened during the East Pacific Ocean and in the Pacific during El Nino El Nino has weakened, improve the planetary wave flux of high latitude upload further leads to a weakening of the polar vortex, the duration of the eastern Pacific during El Nino SSW longer than in the Pacific El.3. in addition to studying the impact of tropical SST of stratospheric sudden warming, the paper uses the data of HadISST and NCEP-NCAR analysis of the data, the WACCM3 model, discusses the tropical Pacific sea surface temperature in winter and North Hemisphere stratospheric sudden warming ties between the study found that the second principal component of North Pacific sea surface temperature (PC2) correlation coefficient of duration of stratospheric sudden warming of the stratosphere is close to the El Nino correlation coefficient of the duration of the explosive temperature increase, the first principal component and correlation coefficient of PC2 and explosive increase duration the temperature is greater than the winter North Pacific sea surface temperature (PC1) and the correlation coefficient of the duration of the explosive increase of temperature. The study also found that in 1980, the duration of time series of SSW of the time series and PC2 exist in the period of oscillation of 10-20 years, consistent with the decadal oscillation and stratospheric sudden warming the duration of the decadal oscillation and PC2. When the PC2 is in a positive phase, stratospheric sudden warming in winter for a longer period of time. When the PC2 is in a negative position, Stratospheric sudden warming in winter shorter duration. Although the PC2 SST anomaly as abnormal extratropical SST, driven mainly by the atmospheric circulation in the tropical, but the WACCM3 model results show that the PC2 SST anomalies, especially in the boundary region of the subtropical Western Pacific SST anomaly has certain feedback effect on the atmosphere, the SST in subtropical the Pacific Ocean near the positive anomaly can produce convective activity more, and then through the circulation and the planetary wave high latitude teleconnction influence, the stratospheric sudden warming affect the effect of.4. by using NCEP-NCAR reanalysis data and HadISST SST data on the duration of the Pacific North American teleconnection and Western Pacific teleconnection different combinations of Stratospheric Sudden Warming. The results show that when the winter Western Pacific teleconnection and Pacific North American teleconnection are positive Phase, duration of SSW was the longest, and when the Western Pacific teleconnection and Pacific North American teleconnection are in negative phase, the duration of SSW is the shortest. In addition, the two combination with tropical SSTA and the Western Pacific sea temperature anomaly is closely related to this paper. Innovation is that although the first mode of the tropical sea temperature variability in the interpretation of the variance is larger, but the effect of the second mode the extra tropical SST of stratospheric sudden warming effect is greater than the first mode.

【学位授予单位】：兰州大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：P732.6;P461.2

【参考文献】