Comparison of Solar and Geomagnetic Activity Effects on the Northern Hemisphere Weather Changes

The changes of pressure and temperature fields in the winter lower troposphere observed in association with changes in solar and/or geomagnetic activity are compared. It is shown that the fact whether it was solar or geomagnetic activity was not so important as whether the levels of the two activities were high or low. The differences between the effects of solar/geomagnetic activity, however, are revealed, the pressure and temperature data being stratified according to the QBO phase. The relationship obtained are discussed from the viewpoint of mechanisms resting upon both the planetary wave propagation and the changes of atmospheric air currents in the global electric circuit.     

60～70oS臭氧总量的QBO和ENSO信号

本文利用Ｎｉｍｂｕｓ－７上搭载的臭氧总量观测光谱仪（ＴＯＭＳ）得到的６０～７０ｏＳ纬圈中臭氧总量资料,分析研究了该地区臭氧总量准两年振荡（ＱＢＯ）和ＥＮＳＯ信号的纬向分布,指出在该纬圈臭氧总量的长期变化中包含着的ＱＢＯ和ＥＮＳＯ信号。同时,本文还分析研究了沿纬圈分布的大气臭氧总量季节变化和长期变化趋势,指出在该纬圈各个季节中臭氧总量呈下降趋势,以６０～１００ｏＷ十月份的下降最大,达到－９．３ＤＵ／ａ。研究同时表明：臭氧总量季节变化、长期变化趋势、以及ＱＢＯ信号的纬向分布都在西南极上空出现异常。本文对此进行了讨论,认为这是西南极海陆分布调整大气环流及大气波动造成对臭氧总量分布和变化的影响     

INTERRELATION BETWEEN EAST-ASIAN WINTER MONSOON AND INDIAN/PACIFIC SST WITH THE INTERDECADAL VARIATION

Investigated statistically is the interrelation between East Asian winter monsoon(EAWM)and SST over sensitive areas of the Indian and Pacific Oceans.with focus on the relation of EAWMto strong ENSO signal area.i.e.,the equatorial eastern Pacific(EEP)SST.Evidence suggeststhat the EAWM variation is intimately associated not only with the EEP SST but with theequatorial western Pacific“warm pool”and equatorial Indian/northwestern Pacific Kuroshio SSTas well:the EAWM and ENSO interact strongly with each other on the interannual time scales,exhibiting pronounced interdecadal variation mainly under the joint effect of the monsoon QBO andthe monsoon/SST background field features on an interdecadal basis—when both fields are in thesame phase(anti-phase).strong EAWM contributes to EEP SST rise(drop)in the followingwinter,corresponding to a warm(cold)ENSO cycle;the EAWM QBO causes ENSO cycle to bestrong phase-locked with seasonal variation,making the EEP SST rise lasting from April—May toMay—June of the next year,which plays an important role in maintaining a warm ENSO phase.     

Interannual variability of the winter stratospheric polar vortex in the Northern Hemisphere and their relations to QBO and ENSO

We investigated the interannual variations of the winter stratospheric polar vortex in this paper. EOF analysis shows that two modes of variability dominate the stratospheric polar vortex on interannual timescales. The leading mode (EOF1) reflects the intensity variation of the polar vortex and is characterized by a geopotential height seesaw between the polar region and the mid-latitudes. The second one (EOF2) exhibits variation in the zonal asymmetric part of the polar vortex, which mainly describes the stationary planetary wave activity. As the strongest interannual variation signal in the atmosphere, the QBO has been shown to influence mainly the strength of the polar vortex. On the other hand, the ENSO cycle, as the strongest interannual variation signal in the ocean, has been shown to be mainly associated with the variation of stationary planetary wave activity in the stratosphere. Possible influences of the stratospheric polar vortex on the tropospheric circulation are also discussed in this paper.     

Interrelation between QBO and 11-year solar cycle effects in total column ozone over Europe

On the basis of total column ozone (TO) data obtained in the period of 1957–2007 at 10 ground-based European stations, characterized by long and highly reliable measurements, the effects of the quasi-biennial oscillation (QBO) and 11-year solar cycle (11-year SC), manifesting in TO are investigated. The results of comparative analysis of seasonal differences between different QBO/solar extremes convincingly demonstrate interrelation between the QBO and 11-year SC effects. It is shown that solar activity modulates the phase of the QBO effect so that the quasi-biennial TO signals during solar maximum and solar minimum are nearly in opposite phase. It is also demonstrated that isolated under permanent conditions of solar minimum or solar maximum the QBO effects in TO have the time scale of about 20 months. Solar modulation of the QBO effect makes the QBO a conductor of the solar cycle impact on TO over Europe. The mechanism of influence of the 11-year SC on the QBO and probably includes its impact on the QBO amplitude in the equatorial lower stratosphere, mainly through weakening of the equatorial easterlies during solar maximum.     

Influence of the 11-year solar cycle on the effects of the equatorial quasi-biennial oscillation, manifesting in the extratropical northern atmosphere

Using the longest and most reliable ozonesonde data sets grouped for four regions (Japan, Europe, as well as temperate and polar latitudes of Canada) the comparative analysis of regional responses of ozone, temperature, horizontal wind, tropopause and surface pressure on the equatorial quasi-biennial oscillation (QBO effects), manifesting in opposite phases of the 11-year solar cycle (11-yr SC) was carried out. The impact of solar cycle is found to be the strongest at the Canadian Arctic, near one of two climatological centres of polar vortex, where in solar maximum conditions the QBO signals in ozone and temperature have much larger amplitudes, embrace greater range of heights, and are maximized much higher than those in solar minimum conditions. The strengthening of the temperature QBO effect during solar maxima can explain why correlation between the 11-yr SC and polar winter stratospheric temperature is reversed in the opposite QBO phases. At the border of polar vortex the 11-yr SC also modulates the QBO effect in zonal wind, strengthening the quasi-biennial modulation of polar vortex during solar maxima that is associated with strong negative correlation between stratospheric QBO signals in zonal wind and temperature. Above Japan the QBO effects of ozone, temperature, and zonal wind, manifesting in solar maxima reveal the downward phase dynamics, reminding similar feature of the zonal wind in the equatorial stratosphere. Above Europe, the QBO effects in solar maxima reveal more similarity with those above Japan, while in solar minima with the effects obtained at the Canadian middle-latitude stations. It is revealed that the 11-yr SC influences regional QBO effects in tropopause height, tropopause temperature and surface pressure. The influence most distinctly manifest itself in tropopause characteristics above Japan. The results of the accompanying analysis of the QBO reference time series testify that in the period of 1965–2006 above 50-hPa level the duration of the QBO cycle in solar maxima is 1–3 months longer than in solar minima. The differences are more distinct at higher levels, but they are diminished with lengthening of the period.     

副热带急流强度和赤道QBO对平流层突然增温的影响

使用一个全球原始方程半谱模式模拟了副热带急流强度和赤道准两年振荡（ＱＢＯ）对平流层突然增温（ＳＳＷ）的影响．结果指出：副热带急流强度对ＳＳＷ有明显影响，副热带急流越强，ＳＳＷ发展越快，极区最大增温区的高度越低；赤道ＱＢＯ不同相位零风线的南北位移对ＳＳＷ没有明显影响；ＱＢＯ东风相位时副热带急流更强，而ＱＢＯ西风相位时副热带急流较弱的观测事实，可能是大的中冬ＳＳＷ更容易发生在ＱＢＯ东风相位的主要原因．     

QUASI-BIENNIAL OSCILLATION IN RAINFALL OVER CHINA*

Based on monthly rainfall data from 80 stations of China for the period of January 1951—February 1985 analysed in terms of the maximum entropy spectrum and EEOF(extended empirical orthogonal function) techniques,the spatial and temporal features of quasi-biennial oscillation(QBO)in the rainfall are investigated in a detailed manner,with some results of interest acquired.Highly evident is the QBO in rainfall over China,especially the mid and lower reaches of the Changjiang River,the NE side of the Qinghai-Xizang Plateau,North China,the southern part of NE China,areas south of the Changjiang River and of the Nanling mountain region,and most of Xinjiang.The spatial wave described by the first and second eigenvectors of EEOF for eastern China is a type of wavetravelling from NE to SW,indicating the cycle of patterns(in the south to north direction):dryness(D)-wetness(W)-dryness(D)→southern W-northern slight D→W-D-W→southern D-northern slight W→D-W-D again,with the flooded region between the Changjiang and Huanghe Rivers for the D-W-D occurrence and with the Changjiang River as the division for the southern W-northern slight D happening.The third and fourth eigenvectors show a standing wave-like feature for the same eastern part,indicating the cycle of D-W-D→transition→W-D-W→transition→D-W-D,again,where the transition means the general weakening of drought and flooding and their subsequent reversal development.The amplitudes of the time coefficients of the first two eigenvectors are opposite in the trend of their changes to those of the next two and show a period of 10—14 years.     

大气准两年振荡的电离层效应

本文研究赤道异常逐日起伏程度的年变化规律,发现它与太阳活动及地磁活动呈微弱的负相关,但却受到QBO的明显调制,QBO东风相起伏加大,QBO西风相起伏减小.这一事实似乎表明,太阳爆发或磁暴不是产生赤道异常逐日起伏的主要原因;而上行行星波的扰动有可能是引起赤道异常逐日起伏的主要原因.