HCl Quasi-Biennial Oscillation in the Stratosphere and a Comparison with Ozone QBO

HALOE data from 1992 to 2003 are used to analyze the interannual variation of the HCl volume mixing ratio and its quasi-biennial oscillation （QBO） in the stratosphere, and the results are compared with the ozone QBO. Then, the NCAR two-dimensional interactive chemical, dynamical and radiative model is used to study the effects of the wind QBO on the distribution and variation of HCl in the stratosphere. The results show that the QBO signals in the HCl mixing ratio are mainly at altitudes from 50 hPa to 5 hPa; the larger amplitudes are located between 30 hPa and 10 hPa; a higher HCl mixing ratio usually corresponds to the westerly phase of the wind QBO and a lower HCl mixing ratio usually corresponds to the easterly phase of the wind QBO in a level near 20 hPa and below. In the layer near 10 hPa-5 hPa, the phase of the HCl QBO reverses earlier than the phase of the wind QBO; the QBO signals for HCl in the extratropics are also clear, but with reversed phase compared with those over the Tropics. The HCl QBO signals at 30°N are clearer than those at 30°S; the QBOs for HCl and ozone have a similar phase at the 50 hPa-20 hPa level while they are out of phase near 10 hPa; the simulated structures of the HCl QBO agree well with observations. The mechanism for the formation of the HCl QBO and the reason for differences in the vertical structure of the HCl and ozone QBO are attributed to the transport of HCl and ozone by the wind QBO-induced meridional circulation.

Teleconnections of Inter-Annual Streamflow Fluctuation in Slovakia with Arctic Oscillation,North Atlantic Oscillation,Southern Oscillation,and Quasi-Biennial Oscillation Phenomena

The aim of the paper is to analyze a possible teleconnection of Quasi-Biennial Oscillation （QBO）, Southern Oscillation （SO）, North Atlantic Oscillation （NAO）, and Arctic Oscillation （AO） phenomena with longterm streamflow fluctuation of the Bela River （1895-2004） and Cierny Hron River （1931-2004） （central Slovakia）. Homogeneity, long-term trends, as well as inter-annual dry and wet cycles were analyzed for the entire 1895-2004 time series of the Bela River and for the 1931-2004 time series of the Cierny Hron River. Inter-annual fluctuation of the wet and dry periods was identified using spectral analysis. The most significant period is that of 3.6 years. Other significant periods are those of 2.35 years, 13.5 years, and 21 years. Since these periods were found in other rivers of the world, as well as in SO, NAO, and AO phenomena, they can be considered as relating to the general regularity of the Earth.

The Features of Ozone Quasi-Biennial Oscillation in Tropical Stratosphere and Its Numerical Simulation

The inlcrunnual variation of the vertical distribution of ozone in the tropical stratosphere and its quasi—biennial oscillation (QBO) is analyzed using HALOE data. The results are compared with the wind QBO. A numerical experiment is carried out to study the effects of wind QBO on the distribution, and variation of ozone in the stratosphere by using (he NCAR interactive chemical, dynamical, and radiative two—dimensional model (SOCRATES). Data analysis shows that the location of the maximum ozone mixing ratio in the stratosphere changes in the meridional and vertical directions, and assumes a quasi—biennial period. The meridional and vertical motion of the maximum mixing ratio leads to a QBO of column ozone and its hemispheric asymmetry. The QBO of the location of the maximum is closely connected with the zonal wind QBO. The data analysis also shows that in the tropical region, the phase of the QBO for ozone density changes many times with height. Numerical simulation shows that the meridional circulation induced by the wind QBO includes three pairs of cells in the stratosphere, which have hemispheric symmetry. The transport of ozone by the induced meridional circulation in various latitudes and heights is the main dynamic cause for the ozone QBO. Cells of the induced circulation in the middle stratosphere (25-35 km) play an important role in producing the ozone QBO.

ON THE INTERACTIONS BETWEEN ENSO AND THE ASIAN MONSOON ON THE SCALE OF QUASI-BIENNIAL OSCILLATION

A diagnostic analysis is performed of the quasi-biennial oscillations during the ENSO cycle and the results are based to study the interactions between ENSO and the Asian monsoons. It shows that the Asian monsoons have significant influence on the ENSO cycle on the quasi-biennial scale. Materialized through the onset and southward progression of the winter monsoon, the influence appears in the tropical western Pacific to excite severe convection and to further affect the ENSO cycle. The phenomenon is not only reflected in the quasi-biennial mode but the annual variation of the Asian winter monsoon in reality.

Quasi-biennial oscillation signal detected in the stratospheric zonal wind at 55–65°N

To investigate the impacts of the quasi-biennial oscillation （QBO） on high-latitude circulation and the Arctic vortex, stratospheric zonal wind at 55-65°N is analyzed. The seasonal cycle, solar cycle, and linear trend in the zonal wind at these latitudes are analyzed and removed, and the QBO signal is retrieved from the monthly zonal wind for the period 1979-2014. The zonal wind has a strong decreasing trend in winter, with a maximum decrease （less than -0.35 m s-1 yr-1） occurring within 70-100°E. The zonal wind has an in-phase response of 1.6 m s-1 to the solar cycle, with a maximum within 100-140°E. A clear QBO signal is detected in the zonal wind during the period 1979-2014, with an amplitude of 2.5 m s-1 and a period of 30 months. The latitudinal distribution of the QBO signal is inhomogeneous, with a maximum within 120-180°E and a minimum within 25-45°E.

Chinese sunspot drawings and their digitization–(Ⅲ)quasi-biennial oscillation of the hand-drawn sunspot records

Quasi-biennial Oscillations(QBOs)of the Sun have a significant meaning as a benchmark of solar cycle,not only for understanding the dynamo action but also in terms of space weather prediction.In this paper,the hand-drawn sunspot images recorded from the Purple Mountain Observatory are used to investigate the solar QBOs and the Gnevyshev gap of the sunspot relative numbers(Rs)and group sunspot numbers(Rg)during the period 1954–2011.The main results are as follows:(1)both the Rs and Rg exhibit similar periods including the 22-year magnetic cycle,the 11-year Schwabe cycle,and the QBOs modes;(2)the reconstructed QBOs of both data sets exhibit coherent behavior and tend to have a high amplitude during the maximum phase of each solar cycle;(3)the Gnevyshev gap is produced by the superposition of the QBOs and the 11-year Schwabe cycle,and the Rs is better to study the variation of the Gnevyshev gap rather than the Rg.

On Quasi-Biennial Oscillation in Air-Sea System

From the COADS (Comprehensive Ocean-Atmosphere Data Set) I and the COADS II, we got a monthly data set of sea surface temperature (SST), zonal and meridional wind components at sea level (U,V) and sea level pressure (SLP) with 4°× 4° grid system covering the period from Jan. 1950 to Dec. 1987 to study the evolutional features of the quasi-biennial oscillation (QBO) in the air-sea system. The analytic method of complex empirical orthogonal function (CEOF) is used to obtain the composite temporal sequences of amplitude (six phases for half a period) for the first and the second main components of SST, U, V and SLP. It is shown from the results that the main characteristics for different phases of the sea surface temperature anomaly's (SSTA) QBO are warm water / cold water in the equator of the eastern Pacific (EEP). There are two warm or cold water centers of the SSTA in the EEP, which are located in the equator of the central Pacific (ECP) and the east part of the EEP. The features of the source propagation and the influence of these two centers on atmospheric circulation are discussed and it can be seen that in the formation of these two centers, there are different features in oceanic and atmospheric circulations and air-sea coupled process.

Quasi-Biennial Oscillations in Atmospheric Ozone from the Chemistry-Climate Model and Ozone Reanalysis

The quasi-biennial oscillation is the primary mode of variability of the equatorial mean zonal wind in the lower stratosphere, which is characterized by downward propagating easterly and westerly wind regimes from 10 hPa level with a period approximately 28 months. The effects of the stratospheric quasi-biennial oscillation in zonal winds (SQBO) are not only confined to atmospheric dynamics but also seen in the chemical constituent (trace gases) anomalies such as ozone, water vapor, carbon monoxide and methane in the lower stratosphere. In this study, we examined the SQBO and associated ozone quasi-biennial oscillation (OQBO) using the chemistry-climate model CHASER (MIROC-ESM) simulations and ECMWF ERA-Interim ozone reanalysis for the period 2000-2015. We used lower stratospheric zonal wind from the radiosonde observations and total column ozone (TCO) from Aura Satellite (OMI Instruments) over Singapore to compare the SQBO and OQBO phases with model and reanalysis. The SQBO shows large variations in magnitude and periodicity during the period of study and the amplitude of OQBO also changes in accordance with the westerly (+ve ozone anomaly) and easterly (-ve ozone anomaly) phases of SQBO. During the Westerly phase of Ozone QBO (WQBO) corresponds to average positive total ozone anomaly of ~10 DU and in the Easterly phase of Ozone QBO (EQBO) corresponds to an average negative total ozone anomaly ~−10 DU in the tropical lower stratosphere. Since the SQBO phases were explained by the vertical propagations of Mixed-Ross by Gravity (MRG) waves and Kelvin waves, the correlation of ozone volume mixing ratio with zonal and vertical velocities gives quasi-biennial signals, which indicate the OQBO mechanism more related to dynamical transport than the stratospheric photochemical variations. Since the average amplitude of OQBO phases gives ~+/−10 DU from the observations during easterly and westerly phases SQBO, we need more research focused on the dynamical transport than the photochemical changes to understand the tropical ozone variability due to the ozone quasi-biennial oscillations.

QBO-like Oscillations Induced by Local Thermal Forcing

A zonalwetiCal two-dimensional equatorial model is used to study the PO￣ty that the long Period oSCillation of the zonal mean now occurring in the lower equatorial stratosphere(QBO) is cause by local thermal activihes at the tropiCal tropopause.The model sumesfully reproduces Q￣like o￣tions of the zonal mean now,suggeshng that the lOCal heating or cooling at the trOPical trOPOpose is Probably the main ￣n of QBO,s generahon. The analysis of the dependence of the oedllahon on the wave foeing iudicatw that the o￣hon is not areaible to the forCing scale.The model can reproduce QBO--like oscillahons with any forCing￣if the forcing Period and amplitude take appropriate valuex, proving that the inaneal cavity waves ge￣od by lOCal thermal sough take much important roles in QBO.

ADVANCE IN STUDIES OF TROPOSPHERIC BIENNIAL OSCILLATION

There are obvious biennial phenomena of circulation, meteorological and climatic elements in the troposphere, named as Tropospheric (Quasi-) Biennial Oscillation (TBO). Many phenomena of TBO are discovered, such as variations of TBO in tropospheric temperature, pressure, winds field, monsoon and subtropical high etc. The mechanism of TBO is explored and the results demonstrate that tropical ocean (the Indian Ocean and the Pacific Ocean, mainly) and Stratospheric QBO play important roles in the TBO. In addition, Eurasian snow cover and solar activity of 11yr period can affect TBO very possibly.

The Characteristics of 30-60 Day Oscillation and Its Relations to the Interannual Oscillations

The characteristics of 30-60 day oscillation (hereafter called LFO ) of the outgoing longwave radiation data (OLR) and its relations to the interannual oscillations of the sea surface temperature (SST) are investigated by using the daily OLR data for the period from January, 1979 to December, 1987 and the corresponding monthly SST data. It is found that the LFO the band the interannual oscillations of the SST monthly anomaly (SSTA) interact each other and they all relate to the occurrence and development of El Nino events closely. Before El Nino event happens, it contributes to the SST's wanning up and to the SST's quasi-biennial oscillation (called QBO for brevity) and three and half years oscillation (called SO for short) being in warm water phase in the equatorial central and eastern Pacific (ECP and EEP) that the LFO in the equatorial western Pacific (EWP) enhances and propagates eastward; When El Nino event takes place, the LFO, SSTA and SSTA's QBO and SO in the EEP interact and strengthen each other; But the warmer SST and the SSTA's QBO and SO in the warm water phase in the EEP contribute to the LFO's weakening in the equatorial Pacific. Moreover, these contribute to the SST in the EEP becoming cold and the SSTA's QBO and SO in the EWP being in cold water phase and then impel the El Nino event to end.

赤道平流层QBO与我国7月雨型的关联

根据１９５３～１９９１年赤道平流层纬向风资料分析，得出我国东部地区７月份主要雨带位置与赤道平流层３０～５０ｈＰａ平均纬向风准两年振荡（以下简称赤道平流层ＱＢＯ）有较好的关联．在西风位相条件下，我国７月主要雨带位置较偏北；在东风位相条件下，我国７月主要雨带位置易偏南．它们之间的关系主要是通过对对流层环流的影响相联系的．利用赤道平流层纬向风的变化规律并结合冬季北太平洋对流层环流特征，对我国７月主要雨带类型的预报，有一定实用意义．

近10年我国降水的QBO分析

近１０年来我国东部地区降水分布趋势的年际变化具有ＱＢＯ特征，双年的降水为中部地区少南北多，单年的降水为中部多南北少，其中江淮流域的降水变化最明显．分析表明，降水ＱＢＯ的特征与西太平洋副高和冷空气活动有关，一般双年副高偏北、亚洲纬向环流发展，雨带偏北；单年相反，副高偏南、亚洲经向环流发展，雨带偏南，江淮流域降水较多．

西太平洋副高活动与平流层QBO关系的研究

资料分析表明，西太平洋副高活动有准两年振荡特征，副高的相对强度和副高脊线的纬度位置都清楚地表现出这种振荡。而且分析还表明，平流层低层纬向风的垂直切变同西太平洋副高活动有关，东（西）风切变对应着脊线位置偏北的较强（弱）副高形势。平流层低层东（西）垂直切变在赤道对流层上部所引起的异常上升（下沉）运动，导致Ｈａｄｌｅｙ环流的异常加强（减弱）可能是平流层ＱＢＯ影响西太平洋副高准两年振荡的重要机制。用ＩＡＰ－ＧＣＭ所作的数值模拟试验得到了同观测资料分析相一致的结果。

太阳黑子、QBO对杭州地区梅雨的影响

分析了1953～2001年杭州梅雨量的周期性振荡特征度其与赤道平流层纬向风之间的关系．结果表明，杭州梅雨量的变化存在着22年左右和准两年左右的周期振荡，雨量和赤道平流层纬向风的准二年振荡（QBO）之间具有相关关系，其相关关系受到太阳活动的调控．在厄尔尼诺年的同期或者后期，QBO和梅雨之间的关系往往会出现异常．

Conceptual model about the interaction between El Nio/ Southern Oscillation and Quasi-Biennial Oscillation in far west equatorial Pacific

Interaction between the Quasi-Biennial Oscillation in far west equatorialPacific (QBOWP) and the El Nino/Southern Oscillation (ENSO) is studied using a new conceptual model.In this conceptual model, the QBOWP effects on ENSO are achieved through two ways: (1) the oceanicKelvin wave along equatorial Pacific, and (2) the Atmospheric Walker Circulation anomaly, while ENSOeffects on QBOWP can be accomplished by the atmospheric Walker Circulation anomaly. Diagnosisanalysis of the model results shows that the Atmospheric bridge (Walker circulation) plays a moreimportant role in interaction between the ENSO and QBOWP than the oceanic bridge (oceanic Kelvinwave along equatorial Pacific); It is found that by the interaction of the ENSO and QBOWP, a freeENSO oscillation with 3-5 years period could be substituted by a oscillation with the quasi-biennialperiod, and the dominant period of SST anomaly and wind anomaly in the far west equatorial Pacifictends to be prolonged with enhanced ENSO forcing. Generally, the multi-period variability in thecoupled Atmosphere-Ocean System in the Tropical Pacific can be achieved through the interactionbetween ENSO and QBOWP.

Evaluating the Brewer–Dobson circulation and its responses to ENSO,QBO,and the solar cycle in different reanalyses

This study compares the climatology and long-term trend of northern winter stratospheric residual mean meridional circulation(RMMC), as well as its responses to El Ni?o-Southern Oscillation(ENSO), stratospheric Quasi Biennial Oscillation(QBO), and solar cycle in ten reanalyses and a stratosphere-resolving model, CESM1-WACCM. The RMMC is a large-scale meridional circulation cell in the stratosphere, usually referred to as the estimate of the Brewer Dobson circulation(BDC). The distribution of the BDC is generally consistent among multiple reanalyses except that the NOAA twentieth century reanalysis(20RC) largely underestimates it. Most reanalyses(except ERA40 and ERA-Interim) show a strengthening trend for the BDC during 1979–2010. All reanalyses and CESM1-WACCM consistently reveal that the deep branch of the BDC is significantly enhanced in El Ni?o winters as more waves from the troposphere dissipate in the stratospheric polar vortex region. A secondary circulation cell is coupled to the temperature anomalies below the QBO easterly center at 50 hPa with tropical upwelling/cooling and midlatitude downwelling/warming, and similar secondary circulation cells also appear between 50–10 hPa and above 10 hPa to balance the temperature anomalies. The direct BDC response to QBO in the upper stratosphere creates a barrier near 30°N to prevent waves from propagating to midlatitudes, contributing to the weakening of the polar vortex. The shallow branch of the BDC in the lower stratosphere is intensified during solar minima, and the downwelling warms the Arctic lower stratosphere. The stratospheric responses to QBO and solar cycle in most reanalyses are generally consistent except in the two 20 CRs.

QBO Features of Tropical Pacific wind Stress Field with the Relation to El Nino

Analysis has been implemented of 1970-1992 tropical Pacific wind stress anomaly and sea surface temperature anomaly (SSTA) datasets, indicating that quasi-biennial oscillation (QBO) of the tropical Pacific WS and SSTA is featured both by a standing and a progressive form, the former emerging in the most intense centers of action and the latter travelling east- or west-ward out of the SSTA sources. Results show that the SSTA is in the warm (cold) phase as zonal component of euqatorial wind stress anomaly gets weakened (reinforced) and the QBO of wind stress anomaly is well related to the El Nino cycle.

Simulation of the equatorial quasi-biennial oscillation based on the parameterization of continuously spectral gravity waves

On the basis of previous parameterization schemes, considering both the wave breaking and absorbed at critical level, a parameterization with a continuous spectrum of gravity waves is realized by introducing a momentum flux density function for the wave spectrum, and then the parameterization scheme of the gravity waves is improved. Choosing parameter values of the background atmosphere and waves based on the observations, a more realistic equatorial quasi-biennial oscillation (QBO) driven by the incorporated drag from the planetary and gravity waves can be simulated. The numerical results indicate that the forcing magnitude of the planetary and gravity waves varies with the wind field, and in some phases of the QBO, the contribution of the gravity waves is comparable with that of the planetary waves. After the QBO is steadily formed, its amplitude and period and wind configuration are relevant to the effect of vertical diffusion and the momentum flux distribution with spectrum, however, independent of the initial background wind field. Moreover, for any given nonzero initial background wind, a steady QBO can be finally generated due to the incorporated drag from the planetary and gravity waves.

ENSO与中国夏季降水的联系:冬季QBO的调制作用

使用NCEP/NCAR再分析资料、中国气象局台站降水资料和GPCC降水资料,系统研究了在冬季平流层准两年振荡(Quasi-Biennial Oscillation, QBO)调制下,厄尔尼诺-南方涛动(El Ni■o-Southern Oscillation,ENSO)不同阶段与中国夏季降水的可能联系。根据两者的位相和强度,可将它们的配置分为QBO西风/El Ni■o、QBO西风/La Ni■a、QBO东风/El Ni■o、QBO东风/La Ni■a。研究结果表明,在年际时间尺度上,ENSO和QBO无显著相关关系。冬季QBO西风位相时,El Ni■o发展年夏季,我国整体偏旱,而华南偏涝;衰减年夏季,华南、华东北部偏旱,东北、长江流域偏涝。La Ni■a发展年夏季,我国东部降水异常呈负-正-负的三极分布;衰减年夏季,东南沿海偏涝。冬季QBO东风位相时,El Ni■o发展年夏季,长江以北偏旱;衰减年夏季,我国东部降水异常呈负-正-负的三极分布。La Ni■a发展年夏季,江淮和华南南部偏旱;衰减年夏季,我国东部沿海偏涝。ENSO是影响我国夏季降水异常的重要因子,而QBO的调制作用在ENSO衰减年夏季更为显著。相比冬季QBO东(西)风位相,QBO西(东)风位相时El Ni■o (La Ni■a)期间赤道西太平洋负(正)海温异常更强,衰减年夏季位于西太平洋的异常下沉(上升)运动和印度洋的异常上升(下沉)运动更强更深厚,西太平洋副热带高压范围更大(小),南亚高压更偏东(西)。