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1.
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. 相似文献
2.
Tropospheric temperature and pressure fields on the Northern Hemisphere in the winter periods 1952–1996 were investigated. Composite maps of those fields, created for the high and low geomagnetic activity and individual quasi-biennial oscillation (QBO), phases show clear differences not only between different levels of geomagnetic activity, but also between the two phases of QBO. Special attention was given to the behaviour of the lower troposphere in January and February 1982. 相似文献
3.
The effect of solar/geomagnetic activity and QBO phase on the distribution of winds prevailing in the winter periods (January–March)
in the Northern Hemisphere at the altitude of 850 mb was studied. Analysis has shown that the zonal flow over the North Atlantic
under high geomagnetic activity intensifies and under low solar/geomagnetic activity weakens. Flow deviations, associated
with geomagnetic activity, are more marked under the QBO-east phase, and flow deviations, associated with solar activity,
are more marked under the QBO-west phase. The results reported by Venne and Dartt (1990) concerning the wind distribution
in the winter (February–March) Northern Hemisphere under high and low solar activity and a QBO-west phase, have been confirmed,
and supplemented with wind distributions under high and low geomagnetic activity. 相似文献
4.
All existing data (6 years) on gravity wave activity, inferred from the nighttime A3 (oblique incidence on the ionosphere) radio wave absorption measurements in the lower ionosphere on 270 kHz at Prhonice in Central Europe, have been exploited to get information on the effects of QBO phases and the Mt. Pinatubo volcanic eruption on the gravity wave activity in the winter half of the year. There appears to be an enhancement of gravity wave activity in the two winters just after the strong volcanic eruption of Mt. Pinatubo. This enhancement is remarkable for long-period waves (T=2–3 hours). No clear effect of the phase of QBO on the level of gravity wave activity has been found; a possible effect of QBO on the correlations between gravity wave activities in individual period bands is indicated. The results are limited by a relatively short data series; however, no more data will he available. 相似文献
5.
Radan Huth Lucie Pokorn Josef Bochní
ek Pavel Hejda 《Journal of Atmospheric and Solar》2009,71(13):1471-1483
We examine joint effects of the solar activity and phase of the quasi-biennial oscillation (QBO) on modes of low-frequency variability of tropospheric circulation in the Northern Hemisphere in winter. The winter months (December–March) are stratified by the solar activity into two (below/above median) classes, and each of these classes is subdivided by the QBO phase (west or east). The variability modes are determined by rotated principal component analysis of 500 hPa heights separately in each class of solar activity and QBO phase. Detected are all the modes known to exist in the Northern Hemisphere. The solar activity and QBO jointly affect the shapes, spatial extent, and intensity of the modes; the QBO effects are, however, generally weaker than those of solar activity. For both solar maxima and minima, there is a tendency to the east/west phase of QBO to be accompanied by a lower/higher activity of zonally oriented modes and increased meridionality/zonality of circulation. This means that typical characteristics of circulation under solar minima, including a more meridional appearance of the modes and less activity of zonal modes, are strengthened during QBO-E; on the other hand, circulation characteristics typical of solar maxima, such as enhanced zonality of the modes and more active zonal modes, are more pronounced during QBO-W. Furthermore, the zonal modes in the Euro-Atlantic and Asian sectors (North Atlantic Oscillation, East Atlantic pattern, and North Asian pattern) shift southwards in QBO-E, the shift being stronger in solar maxima. 相似文献
6.
《Journal of Atmospheric and Solar》2008,70(5):764-773
Quasi-biennial oscillation (QBO) is a predominant phenomenon in the tropical stratosphere and troposphere. The possible interactions between the stratospheric QBO and tropospheric biennial oscillation (TBO) over the Indian monsoon region as well as the equatorial region is investigated using the zonal wind data of 23 vertical levels (1000–1 hpa) from 1960–2002. The structure of lower stratosphere and troposphere are entirely different over the equator and India. In biennial scales, both the stratosphere and troposphere over the Indian region are closely related and winter season QBO is a good predictor of Indian summer monsoon rainfall. 相似文献
7.
R. P. Kane 《Annales Geophysicae》1995,13(2):211-216
Stratospheric temperatures show distinct trends, not necessarily monotonically upward or downward. At the North Pole, trends were large only during winter and spring and were different for different months; downward for November, December, mixed for January and upward for February, March and April. For the 10°-90°N belt, the trends were variable, viz., downward during 1971-1975, upward during 1975–1978 and downward again from 1978 onwards up to date, opposite to the upward trend of ground temperature in the Northern hemisphere in recent years. Twelve-monthly running averages revealed strong QBO (quasi-biennial oscillation). For the North Pole, the QBO showed colder (lower) temperatures during 50-mb wind QBO westerly phase maxima. For the 10°-90°N belt, the QBO was similar for 30 mb and 50 mb but the QBO phases did not match well with 50-mb wind QBO phases. 相似文献
8.
Two different equatorial quasi-biennial oscillation (QBO) indices, two reanalyses and radiosonde observations are used to analyze the Arctic stratospheric temperature and height. This analysis was used to assess the uncertainties in the connection of solar forcing, QBO and the Arctic variability. The results show that (1) the frequency of the westerly/easterly phases of the QBO over the stratospheric equator has a significant multiple peak seasonal variation. The primary seasonal peaks occur in February, March and April for the westerly phase of the QBO and the easterly phase peaks in June, July and August. (2) The correlation of stratospheric Arctic temperature and height with the solar radio flux shows statistical significance in February or July/August even if there is no stratified phase of QBO (easterly and westerly phases) involved. However, when the correlation was computed according to the stratified phase of QBO, the solar signals in both temperature and height fields are remarkably amplified in February and November under the westerly phase, but the signal in the height field is most significant only in August under the easterly phase. (3) The impact of the QBO and solar forcing on the stratospheric temperature and heights in the Arctic varies depending on the season. The impacts are also sensitive to the specific height of the QBO-defined level that is used, the specific period of the analysis and the dataset used. 相似文献
9.
Dynamical mechanism of the stratospheric quasibiennial oscillation impact on the South China Sea Summer Monsoon 总被引：1，自引：0，他引：1
The National Center for the Atmospheric Research (NCAR) middle atmospheric model is used to study the effects of the quasi-biennial oscillation in the stratosphere (QBO) on the tropopause and uppe troposphere, and the relationship between the QBO and South China Sea Summer Monsoon (SCSSM is explored through NCEP (the National Centers for Environmental Prediction)/NCAR, ECMWF (Euro pean Centre for Medium-Range Weather Forecasts) monthly mean wind data and in situ sounding data The simulations show that the QBO-induced residual circulations propagate downwards, and affect the tropopause and upper troposphere during the periods of mid-late QBO phase and phase transition Meanwhile, diagnostic analyses indicate that anomalous circulation similar to SCSSM circulation is generated to strengthen the SCSSM during the easterly phase and anomalous Hadley-like circulation weakens the SCSSM during the westerly. Though the QBO has effects on the SCSSM by meridiona circulation, it is not a sole mechanism on the SCSSM TBO mode. 相似文献
10.
R. P. Kane 《Pure and Applied Geophysics》1996,147(3):567-583
A spectral analysis of the 12-month running averages of several atmospheric parameters for 40 years (1951–1990) indicated prominent QBO (Quasi-Biennial Oscillations) and QTO (Quasi-Triennial Oscillations). The 50 mb tropical wind has a very prominent QBO peak atT=2.33 years, which was well reflected in N. Pole 30 mb temperature but not in average surface air temperatures of Northern and Southern Hemispheres. The 50 mb wind had no prominent QTO; but sea-surface temperatures showed prominent QTO at 3.6 years as well as peaks at 4.8 years (also shown by N. Pole 30 mb temperature) which matched very well with similar peaks in the Pacific SST and SO (Southern Oscillation) index. Specific humidity in the lower troposphere (1000 and 700 mb) and temperature at 300 mb obtained by radiosondes in the western Pacific for 15 years (1974–1988) showed mainly a biennial oscillation. 相似文献
11.
Evgeny A. Jadin Ke Wei Yulia A. Zyulyaeva Wen Chen Lin Wang 《Journal of Atmospheric and Solar》2010,72(16):1163-1170
Using the monthly mean NCEP/NCAR reanalysis and NOAA Extended Reconstructed sea surface temperature (SST) datasets, strong correlations between the SST anomalies in the North Pacific and calculated three-dimensional Eliassen–Palm vertical fluxes are indicated in December 1958–1976 and 1992–2006. These correlations between the interannual variations of the SST anomalies and the penetration of planetary waves into the stratosphere are much less during the decadal sub-period 1976–1992 in the positive phase of the Pacific Decadal Oscillation (PDO) and the decadal cold SST anomalies in the North Pacific. Interannual variations of the polar jet in the lower stratosphere in January are strongly associated with SST anomalies in the Aleutian Low region in December for the years with positive PDO index. This sub-period corresponds well with that of the violation of the Holton–Tan relationship between the equatorial Quasi-Beinnial Oscillation (QBO) and the stratospheric circulation in the extra-tropics. It is shown that interannual and interdecadal variations of stratospheric dynamics, including stratospheric warming occurrences in January, depend strongly on changes of the upward propagation of planetary waves from the troposphere to the stratosphere over North Eurasia in preceding December. These findings give evidences of a large impact of the decadal SST variations in the North Pacific on wave activity in early winter due to changes of thermal excitation of planetary waves during distinct decadal periods. Possible causes of the decadal violation of the Holton–Tan relationship, its relation to the PDO and an influence of the 11-year solar cycle on the stratosphere are discussed. 相似文献
12.
文中利用逐次滤波法滤除北半球平流层70 hPa约15~22 km高空大气温度异常变化中太阳活动的影响之后,进一步分析了火山活动的气候效应,分析结果表明,火山活动能引起平流层较大幅度增温,对于北半球70hPa高空气候异常变化的影响超过了总方差的30%;火山活动影响最显著的高度是平流层70 hPa约15~22 km高空,由此高度向上或向下,火山活动的影响都逐渐减小;火山活动引起平流层大气升温的同时还将引起对流层大气降温,其分界线大致位于对流层顶300 hPa附近;强火山爆发如皮纳图博火山爆发、阿贡火山爆发和堪察加北楮缅奴等火山爆发是引起未来两年左右平流层中下层温度异常变化最重要的因素,其方差贡献率超过百分之五十三！;火山喷发高度越高,引起平流层增温效应的层次也越高;北半球大气温度异常变化对南半球火山活动响应的滞后时间比北半球火山活动长. 平流层高空气候异常变化还具有显著的22年变化周期,分析认为是大气温度场对太阳磁场磁性周期22年异常变化的响应,其方差贡献率超过9%. 相似文献
13.
Spatiotemporal variations of the quasi-biennial oscillation (QBO) in temperature and ozone over the tropical–subtropical belts (40°N–40°S) have been studied using Microwave Limb Sounder data for the period 1992–1999. Wavelet analysis has been performed to study inter-annual variations in amplitude and phases of the QBO. Latitude-height cross-sections of the amplitudes of temperature and ozone QBO exhibit a double-peak structure near the equator. Phase structure reveals that the temperature QBO descended faster than the ozone QBO. Cross-wavelet analysis shows an anti-phase relation between the amplitudes of the temperature and ozone QBO in the upper stratospheric region, whereas in-phase relation exists in the middle stratospheric region. 相似文献
14.
Peng K. Hong Hiroko Miyahara Yusuke Yokoyama Yukihiro Takahashi Mitsuteru Sato 《Journal of Atmospheric and Solar》2011,73(5-6):587-591
We examined the effect of the 11-year solar cycle and quasi-biennial oscillation (QBO) on the ～27-day solar rotational period detected in tropical convective cloud activity. We analyzed the data of outgoing longwave radiation (OLR) for AD1979–2004, dividing into four different cases by the combination of high and low solar activities in terms of the 11-year variation, and easterly and westerly stratospheric winds associated with QBO. As a result, ～27-day variation has been most significantly detected in high solar activity period around the Indo-Pacific Warm Pool. Based on correlation analysis, we find that solar rotation signal can explain 10–20% of OLR variability around the tropical warm pool region during the high solar activity period. The spatial distribution has been, however, apparently different according to the phases of QBO. It is suggested that the 11-year solar cycle and stratospheric QBO have a possibility to cause large-scale oceanic dipole phenomena. 相似文献
15.
B. Soukharev 《Annales Geophysicae》1997,15(12):1595-1603
The interaction between the factors of the quasi-biennial oscillation (QBO) and the 11-year solar cycle is considered as an separate factor influencing the interannual January–March variations of total ozone over Northeastern Europe. Linear correlation analysis and the running correlation method are used to examine possible connections between ozone and solar activity at simultaneous moment the QBO phase. Statistically significant correlations between the variations of total ozone in February and, partially, in March, and the sunspot numbers during the different phases of QBO are found. The running correlation method between the ozone and the equatorial zonal wind demonstrates a clear modulation of 11-y solar signal for February and March. Modulation is clearer if the QBO phases are defined at the level of 50 hPa rather than at 30 hPa. The same statistical analyses are conducted also for possible connections between the index of stratospheric circulation C1 and sunspot numbers considering the QBO phase. Statistically significant connections are found for February. The running correlations between the index C1 and the equatorial zonal wind show the clear modulation of 11-y solar signal for February and March. Based on the obtained correlations between the interannual variations of ozone and index C1, it may be concluded that a connection between solar cycle – QBO – ozone occurs through the dynamics of stratospheric circulation. 相似文献
16.
利用气象场的再分析资料和太阳辐射活动资料,对太阳11年周期活动影响北半球冬季(11月~3月)大气环流的过程进行了统计分析和动力学诊断.根据赤道平流层纬向风准两年振荡(QBO)的东、西风状态对太阳活动效应进行了分类讨论,结果表明：东风态QBO时,太阳活动效应主要集中在赤道平流层中、高层和南半球平流层,强太阳活动时增强的紫外辐射加热了赤道地区的臭氧层,造成平流层低纬明显增温,同时加强了南半球的Brewer-Dobson(B-D)环流,引起南极高纬平流层温度增加;而北半球中高纬的环流主要受行星波的影响,太阳活动影响很小.西风态QBO时,太阳活动效应在北半球更为重要,初冬时强太阳活动除了加热赤道地区臭氧层外,还抑制了北半球的B-D环流,造成赤道平流层温度增加和纬向风梯度在垂直方向的变化,从而改变了对流层两支行星波波导的强度;冬末时在太阳活动调制下,行星波向极波导增强,B-D环流逐渐恢复,造成北半球极地平流层明显增温,同时伴随着赤道区域温度的下降. 相似文献
17.
分析了1993年到2002年10年间HALOE卫星资料的热带平流层水汽年际变率,结果表明：热带平流层水汽混合比在2~5 hPa、10~30 hPa、30~100 hPa有三组显著的准两年周期振荡（QBO）现象;其中2~5 hPa和10~30 hPa水汽QBO呈反位相循环;30~100 hPa水汽QBO有显著上传特性.SOCRATES3模式模拟和诊断结果表明,热带平流层水汽QBO是在纬向风QBO强迫下产生的次级动力、热力因子和化学作用耦合后的结果：上层主要是环流输送引起,中层是环流输送和温度扰动驱动下的化学作用引起,下层是对流层顶水汽冻结层的温度扰动和环流输送引起. 相似文献
18.
The spectral structure of stratospheric fields (temperature and geopotential) is analyzed in terms of spherical harmonics in an effort to study the long-term behaviour of large-scale circulation patterns, as well as their connections to some extra-terrestrial effects. The daily meteorological data from the Free University Berlin (FUB) cover more or less the period 1976–1996 and are available for stratospheric levels of 50, 30 and 10 hPa. The analysis of the annual cycle of spherical harmonics is introduced, and changes of the principal wave components are compared with the changes in different sets of solar, geomagnetic and global circulation indices. This paper also deals with interannual variability with special emphasis on quasibiennial oscillations (QBO) and El Nino and Southern Oscillations (ENSO).
Although this is a rather preliminary study, the decomposition of the stratospheric field into complex spherical harmonics seems to be a powerful technique in investigating and qualifying the response of the global atmospheric system to the changes in solar and geomagnetic activity, and in qualifying the relationships between large-scale circulation patterns and various oscillations such as QBO or ENSO, Using this technique, reasonable strong connections were found between wave numbers and interannual factors, and these connections were tentatively interpreted in terms of statistics. A very high degree of correlation was found for the four-trough shape of the polar vortex. 相似文献
19.
We present results from the Numerical Spectral Model (NSM), which focus on the temperature environment of the mesopause region where polar mesospheric clouds (PMC) form. The PMC occur in summer and are observed varying on time scales from months to years, and the NSM describes the dynamical processes that can generate the temperature variations involved. The NSM simulates the quasi-biennial oscillation (QBO), which dominates the zonal circulation of the lower stratosphere at equatorial latitudes. The modeled QBO extends into the upper mesosphere, due to gravity wave (GW) filtering, consistent with UARS zonal wind and TIMED temperature measurements. While the QBO zonal winds are confined to equatorial latitudes, the associated temperature variations extend to high latitudes. The meridional circulation redistributes the QBO energy—and the resulting temperature oscillations away from the equator produce inter-annual variations that can exceed 5 K in the polar mesopause region, with considerable differences between the two hemispheres. The NSM shows that the 30-month QBO produces a 5-year or semi-decadal (SD) oscillation, and stratospheric NCEP data provide observational evidence for that. This SD oscillation extends in the temperature to the upper mesosphere, where it could contribute to the long-term variations of the region. 相似文献
20.
—The 4-season (12-month) running means of temperatures at five atmospheric levels (surface, 850–300 mb, 300–100 mb, 100–50 mb, 100–30 mb) and seven climatic zones (60°N–90°N, 30°N–60°N, 10°N–30°N, 10°N–10°S, 10°S–30°S, 30°S–60°S, 60°S–90°S) showed QBO (Quasi-biennial Oscillation), QTO (Quasi-triennial Oscillation) and larger periodicities. For stratosphere and tropopause, the temperature variations near the equator and North Pole somewhat resembled the 50mb low latitude zonal winds, mainly due to prominent QBO. For troposphere and surface, the temperature variations, especially those near the equator, resemble those of eastern equatorial Pacific sea-surface temperatures, mainly due to prominent QTO. In general, the temperature trends in the last 35 years show stratospheric cooling and tropospheric warming. But the trends are not monotonic. For example, the surface trends were downward during 1960–70, upward during 1970–82, downward during 1982–85 and upward thereafter. Models of green-house warming should take these non-uniformities into account. 相似文献