Future Changes in the Ozone Quasi-Biennial Oscillation with Increasing GHGs and Ozone Recovery in CCMI Simulations

The future quasi-biennial oscillation (QBO) in ozone in the equatorial stratosphere is examined by analyzing transient climate simulations due to increasing greenhouse gases (GHGs) and decreasing ozone-depleting substances under the auspices of the Chemistry–Climate Model Initiative. The future (1960–2100) and historical (1979–2010) simulations are conducted with the Meteorological Research Institute Earth System Model. Three climate periods, 1960–85 (past), 1990–2020 (present), and 2040–70 (future) are selected, corresponding to the periods before, during, and after ozone depletion. The future ozone QBO is characterized by increases in amplitude by 15%–30% at 5–10 hPa and decreases by 20%–30% at 40 hPa, compared with the past and present climates; the future and present ozone QBOs increase in amplitude by up to 60% at 70 hPa, compared with the past climate. The increased amplitude at 5–10 hPa suggests that the temperature-dependent photochemistry plays an important role in the enhanced future ozone QBO. The weakening of vertical shear in the zonal wind QBO is responsible for the decreased amplitude at 40 hPa in the future ozone QBO. An interesting finding is that the weakened zonal wind QBO in the lowermost tropical stratosphere is accompanied by amplified QBOs in ozone, vertical velocity, and temperature. Further study is needed to elucidate the causality of amplification about the ozone and temperature QBOs under climate change in conditions of zonal wind QBO weakening.

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The Influence of the Quasi-Biennial Oscillation on the Troposphere in Winter in a Hierarchy of Models. Part I: Simplified Dry GCMs

Journal of the Atmospheric Sciences ◽

10.1175/2011jas3665.1 ◽

2011 ◽

Vol 68 (6) ◽

pp. 1273-1289 ◽

Cited By ~ 50

Author(s):

Chaim I. Garfinkel ◽

Dennis L. Hartmann

Keyword(s):

Zonal Wind ◽

Climate Model ◽

Polar Vortex ◽

Equation Model ◽

Quasi Biennial Oscillation ◽

Stratospheric Polar Vortex ◽

The North ◽

Subtropical Jet ◽

Long Time ◽

Biennial Oscillation

Abstract A dry primitive equation model is used to explain how the quasi-biennial oscillation (QBO) of the tropical stratosphere can influence the troposphere, even in the absence of tropical convection anomalies and a variable stratospheric polar vortex. QBO momentum anomalies induce a meridional circulation to maintain thermal wind balance. This circulation includes zonal wind anomalies that extend from the equatorial stratosphere into the subtropical troposphere. In the presence of extratropical eddies, the zonal wind anomalies are intensified and extend downward to the surface. The tropospheric response differs qualitatively between integrations in which the subtropical jet is strong and integrations in which the subtropical jet is weak. While fluctuation–dissipation theory provides a guide to predicting the response in some cases, significant nonlinearity in others, particularly those designed to model the midwinter subtropical jet of the North Pacific, prevents its universal application. When the extratropical circulation is made zonally asymmetric, the response to the QBO is greatest in the exit region of the subtropical jet. The dry model is able to simulate much of the Northern Hemisphere wintertime tropospheric response to the QBO observed in reanalysis datasets and in long time integrations of the Whole Atmosphere Community Climate Model (WACCM).

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The Effects of Changes in Sea Surface Temperature and CO2 Concentration on the Quasi-Biennial Oscillation

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-11-0265.1 ◽

2012 ◽

Vol 69 (5) ◽

pp. 1734-1749 ◽

Cited By ~ 10

Author(s):

Yoshio Kawatani ◽

Kevin Hamilton ◽

Akira Noda

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Lower Stratosphere ◽

Climate Model ◽

Equatorial Region ◽

Sea Surface ◽

Quasi Biennial Oscillation ◽

Wave Forcing ◽

The Future ◽

Biennial Oscillation

Abstract The effects of sea surface temperature (SST) and CO2 on future changes in the quasi-biennial oscillation (QBO) are investigated using a climate model that simulates the QBO without parameterized nonstationary gravity wave forcing. Idealized model experiments using the future SST with the present CO2 (FS run) and the present SST with the future CO2 (FC run) are conducted, as are experiments using the present SST with the present CO2 (present run) and the future SST with the future CO2 (future run). When compared with the present run, precipitation increases around the equatorial region in the FS run and decreases in the FC run, resulting in increased and decreased wave momentum fluxes, respectively. In the midlatitude lower stratosphere, westward (eastward) wave-forcing anomalies form in the FS (FC) run. In the middle stratosphere off the equator, westward wave-forcing anomalies form in both the FS and FC runs. Corresponding to these wave-forcing anomalies, the residual vertical velocity significantly increases in the lower stratosphere in the FS run but decreases to below 70 hPa in the FC run, whereas residual upward circulation anomalies form in both the FS and FC runs in the middle equatorial stratosphere. Consequently, the amplitude of the QBO becomes smaller in the lower stratosphere, and the period of the QBO becomes longer by about 1–3 months in the FS run. On the other hand, in the FC run, the QBO extends farther downward into the lowermost stratosphere, and the period becomes longer by 1 month.

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On the Momentum Budget of the Quasi-Biennial Oscillation in the Whole Atmosphere Community Climate Model

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-18-0088.1 ◽

2018 ◽

Vol 76 (1) ◽

pp. 69-87 ◽

Cited By ~ 24

Author(s):

Rolando R. Garcia ◽

Jadwiga H. Richter

Keyword(s):

Gravity Waves ◽

Climate Model ◽

Equatorial Waves ◽

Quasi Biennial Oscillation ◽

Community Climate Model ◽

Westerly Jet ◽

Momentum Budget ◽

Zonal Wavenumber ◽

Biennial Oscillation ◽

Community Climate

Abstract This study documents the contribution of equatorial waves and mesoscale gravity waves to the momentum budget of the quasi-biennial oscillation (QBO) in a 110-level version of the Whole Atmosphere Community Climate Model. The model has high vertical resolution, 500 m, above the boundary layer and through the lower and middle stratosphere, decreasing gradually to about 1.5 km near the stratopause. Parameterized mesoscale gravity waves and resolved equatorial waves contribute comparable easterly and westerly accelerations near the equator. Westerly acceleration by resolved waves is due mainly to Kelvin waves of zonal wavenumber in the range k = 1–15 and is broadly distributed about the equator. Easterly acceleration near the equator is due mainly to Rossby–gravity (RG) waves with zonal wavenumbers in the range k = 4–12. These RG waves appear to be generated in situ during both the easterly and westerly phases of the QBO, wherever the meridional curvature of the equatorial westerly jet is large enough to produce reversals of the zonal-mean barotropic vorticity gradient, suggesting that they are excited by the instability of the jet. The RG waves produce a characteristic pattern of Eliassen–Palm flux divergence that includes strong easterly acceleration close to the equator and westerly acceleration farther from the equator, suggesting that the role of the RG waves is to redistribute zonal-mean vorticity such as to neutralize the instability of the westerly jet. Insofar as unstable RG waves might be present in the real atmosphere, mixing due to these waves could have important implications for transport in the tropical stratosphere.

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Quasi-Biennial Oscillation in Stratospheric Zonal Wind and Indian Summer Monsoon

Monthly Weather Review ◽

10.1175/1520-0493(1985)113<1421:qboisz>2.0.co;2 ◽

1985 ◽

Vol 113 (8) ◽

pp. 1421-1424 ◽

Cited By ~ 32

Author(s):

B. K. Mukherjee ◽

K. Indira ◽

R. S. Reddy ◽

Bh V. Ramana Murty

Keyword(s):

Summer Monsoon ◽

Indian Summer Monsoon ◽

Zonal Wind ◽

Quasi Biennial Oscillation ◽

Biennial Oscillation

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Analysis of Arctic Spring Ozone Anomaly in the Phases of QBO and 11-year Solar Cycle for 1979–2011

10.20944/preprints202104.0057.v1 ◽

2021 ◽

Author(s):

Yousuke Yamashita ◽

Hideharu Akiyoshi ◽

Masaaki Takahashi

Keyword(s):

Solar Cycle ◽

Climate Model ◽

Polar Vortex ◽

Reanalysis Data ◽

Early Spring ◽

The Arctic ◽

Negative Anomaly ◽

Late Winter ◽

Quasi Biennial Oscillation ◽

Biennial Oscillation

Arctic ozone amount in winter to spring shows large year-to-year variation. This study investigates Arctic spring ozone in relation to the phase of quasi-biennial oscillation (QBO)/the 11-year solar cycle, using satellite observations, reanalysis data, and outputs of a chemistry climate model (CCM) during the period of 1979–2011. For this duration, we found that the composite mean of the Northern Hemisphere high-latitude total ozone in the QBO-westerly (QBO-W)/solar minimum (Smin) phase is slightly smaller than those averaged for the QBO-W/Smax and QBO-E/Smax years in March. An analysis of a passive ozone tracer in the CCM simulation indicates that this negative anomaly is primarily caused by transport. The negative anomaly is consistent with a weakening of the residual mean downward motion in the polar lower stratosphere. The contribution of chemical processes estimated using the column amount difference between ozone and the passive ozone tracer is between 10–20% of the total anomaly in March. The lower ozone levels in the Arctic spring during the QBO-W/Smin years are associated with a stronger Arctic polar vortex from late winter to early spring, which is linked to the reduced occurrence of sudden stratospheric warming in the winter during the QBO-W/Smin years.

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Large internal variability dominates over global warming signal in observed lower stratospheric QBO amplitude

Journal of Climate ◽

10.1175/jcli-d-21-0270.1 ◽

2021 ◽

pp. 1-43

Author(s):

Aaron Match ◽

Stephan Fueglistaler

Keyword(s):

Global Warming ◽

Climate Model ◽

Global Climate ◽

Global Climate Model ◽

Internal Variability ◽

Dynamical Process ◽

Quasi Biennial Oscillation ◽

Amplitude Profile ◽

Biennial Oscillation ◽

Middle Stratosphere

AbstractGlobal warming projections of dynamics are less robust than projections of thermodynamics. However, robust aspects of the thermodynamics can be used to constrain some dynamical aspects. This paper argues that tropospheric expansion under global warming (a thermodynamical process) explains changes in the amplitude of the Quasi-Biennial Oscillation (QBO) in the lower and middle stratosphere (a dynamical process). A theoretical scaling for tropospheric expansion of approximately 6 hPa K−1 is derived, which agrees well with global climate model (GCM) experiments. Using this theoretical scaling, the response of QBO amplitude to global warming is predicted by shifting the climatological QBO amplitude profile upwards by 6 hPa per Kelvin of global warming. In global warming simulations, QBO amplitude in the lower- to mid-stratosphere shifts upwards as predicted by tropospheric expansion. Applied to observations, the tropospheric expansion framework suggests a historical weakening of QBO amplitude at 70 hPa of 3% decade−1 from 1953-2020. This expected weakening trend is half of the 6% decade−1 from 1953-2012 detected and attributed to global warming in a recent study. The previously reported trend was reinforced by record low QBO amplitudes during the mid-2000s, from which the QBO has since recovered. Given the modest weakening expected on physical grounds, past decadal modulations of QBO amplitude are reinterpreted as a hitherto unrecognized source of internal variability. This large internal variability dominates over the global warming signal, such that despite 65 years of observations, there is not yet a statistically significant weakening trend.

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Observational evidences of the influences of tropospheric subtropical and midlatitude stratospheric westerly jets on the equatorial stratospheric intraseasonal oscillations

10.5194/acp-2016-118 ◽

2016 ◽

Author(s):

G. Karthick Kumar Reddy ◽

T. K. Ramkumar ◽

S. Venkatramana Reddy

Keyword(s):

Zonal Wind ◽

Lower Atmosphere ◽

Theoretical Modelling ◽

Quasi Biennial Oscillation ◽

Medium Range Weather Forecast ◽

Westerly Jet ◽

Longitudinal Sector ◽

Vertical Propagation ◽

Biennial Oscillation ◽

Subtropical Westerly Jet

Abstract. Using six Global Positioning System (GPS) Radio Occultation (RO) satellites (SAC-C, METOP-A and COSMIC/FORMOSAT-3, CNOFS, GRACE and TerraSAR-X) determined height profiles (1–40 km) of atmospheric temperature over the Indian tropical station of Gadanki and the European Center for Medium Range Weather Forecast (ECMWF) Interim Reanalyses (ERA-Interim) zonal wind and temperature data for four years (2009–2012), the present work reports that the tropospheric Subtropical Westerly Jet (SWJ) and the Midlatitude Stratospheric Westerly Jet (MStWJ) play important roles in controlling differently the vertical propagation of tropical Intra Seasonal Oscillations (ISO) with different period bands from the troposphere up to the stratosphere during Northern winters. In the months of December–May (Northern winter to summer, NWTS) of all these years, there is significant 10–20 day and 20–40 day oscillations in the troposphere up to the height of 13 km and above this it reappears at all heights above 21 km. The 40–80 day oscillation also shows similar characteristics except that it almost disappeared during NWTS months of the year 2010–2011 in the stratosphere. The absence of these signals in the intervening heights of ~ 17–20 km is explained on the basis that these two bands actually propagate from the tropical to subtropical region near the tropopause and then reappears in the tropical stratosphere after refracted by the subtropical westerly jet. The poleward and equatorward propagation of these bands in the troposphere and stratosphere respectively are found using the ERA-interim data. Further the two longer period bands of ISO show strong quasi-biennial oscillation in the lower atmosphere with opposite phases (when one band shows maximum the other one shows minimum in a particular year) between these two bands. It is also observed that the phase of the tropical stratospheric Quasi Biennial Oscillation (QBO) has significant control on the strength of the Mid latitude stratospheric westerly jet (MStWJ) that in turn controls the refraction of the tropical tropospheric longer (40–80 days, Longer period ISO; LISO) but not the smaller periods of ISO (SISO) back to the tropical stratosphere. In accordance with earlier theoretical modelling studies, the westerly phase of the lower stratospheric QBO occurred during NWTS months of 2010–2011 over the Indian longitudinal sector causes severe disruption of the MStWJ at 30 km height. This disruption caused the prevention of refraction back again to the tropical stratosphere of significant tropospheric LISO that arrived from the tropics through the tropopause. Further, in these four years, it is observed no direct vertical propagation of tropical tropospheric ISO to the stratosphere. The interannual variations in the tropical stratospheric LISO are related strongly to the phase of the equatorial lower stratospheric QBO in zonal wind and the strength of the MStWJ.

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Influence of the Quasi-Biennial Oscillation on the Extratropical Winter Stratosphere in an Atmospheric General Circulation Model and in Reanalysis Data

Journal of the Atmospheric Sciences ◽

10.1175/2009jas3292.1 ◽

2010 ◽

Vol 67 (5) ◽

pp. 1402-1419 ◽

Cited By ~ 31

Author(s):

James A. Anstey ◽

Theodore G. Shepherd ◽

John F. Scinocca

Keyword(s):

Zonal Wind ◽

General Circulation ◽

Polar Vortex ◽

Reanalysis Data ◽

Empirical Orthogonal Functions ◽

Vertical Profiles ◽

Quasi Biennial Oscillation ◽

Stratospheric Polar Vortex ◽

Atmospheric General Circulation ◽

Biennial Oscillation

Abstract The interannual variability of the stratospheric polar vortex during winter in both hemispheres is observed to correlate strongly with the phase of the quasi-biennial oscillation (QBO) in tropical stratospheric winds. It follows that the lack of a spontaneously generated QBO in most atmospheric general circulation models (AGCMs) adversely affects the nature of polar variability in such models. This study examines QBO–vortex coupling in an AGCM in which a QBO is spontaneously induced by resolved and parameterized waves. The QBO–vortex coupling in the AGCM compares favorably to that seen in reanalysis data [from the 40-yr ECMWF Re-Analysis (ERA-40)], provided that careful attention is given to the definition of QBO phase. A phase angle representation of the QBO is employed that is based on the two leading empirical orthogonal functions of equatorial zonal wind vertical profiles. This yields a QBO phase that serves as a proxy for the vertical structure of equatorial winds over the whole depth of the stratosphere and thus provides a means of subsampling the data to select QBO phases with similar vertical profiles of equatorial zonal wind. Using this subsampling, it is found that the QBO phase that induces the strongest polar vortex response in early winter differs from that which induces the strongest late-winter vortex response. This is true in both hemispheres and for both the AGCM and ERA-40. It follows that the strength and timing of QBO influence on the vortex may be affected by the partial seasonal synchronization of QBO phase transitions that occurs both in observations and in the model. This provides a mechanism by which changes in the strength of QBO–vortex correlations may exhibit variability on decadal time scales. In the model, such behavior occurs in the absence of external forcings or interannual variations in sea surface temperatures.

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Numerical modeling of the natural and anthropogenic factors influence on the past and future changes in polar, mid-latitude and tropical ozone

10.5194/egusphere-egu2020-20440 ◽

2020 ◽

Author(s):

Sergei Smyshlyaev ◽

Polina Blakitnaya ◽

Maxim Motsakov ◽

Vener Galin

Keyword(s):

Solar Activity ◽

Greenhouse Gases ◽

Climate Model ◽

Middle Atmosphere ◽

Stratospheric Ozone ◽

Stratospheric Aerosol ◽

Anthropogenic Factors ◽

The Past ◽

Ozone Depleting Substances ◽

Natural And Anthropogenic Factors

<p>The INM RAS &#8211; RSHU chemistry-climate model of the lower and middle atmosphere is used to compare the role of natural and anthropogenic factors in the observed and expected variability of stratospheric ozone. Numerical experiments have been carried out on several scenarios of separate and combined effects of solar activity, stratospheric aerosol, sea surface temperature, greenhouse gases, and ozone-depleting substances emissions on ozone for the period from 1979 to 2050. Simulations for the past and present periods are compared to the results of ground-based and satellite observations, as well as MERRA and ERA-Interim re-analysis. Estimation of future ozone changes are based on different scenarios of changes in solar activity and emissions of ozone-depleting substances and greenhouse gases, as well as the possibility of large volcanic aerosol emissions at different periods of time.</p>

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Influence of the Equatorial QBO on the Extratropical Stratosphere

Journal of the Atmospheric Sciences ◽

10.1175/jas3657.1 ◽

2006 ◽

Vol 63 (3) ◽

pp. 936-951 ◽

Cited By ~ 18

Author(s):

John Hampson ◽

Peter Haynes

Keyword(s):

Correlation Coefficient ◽

Zonal Wind ◽

Potential Temperature ◽

Lower Boundary ◽

Quasi Biennial Oscillation ◽

Wave Forcing ◽

Least Squares Fit ◽

Phase Alignment ◽

Biennial Oscillation ◽

Extratropical Circulation

Abstract The work described here examines the influence of the equatorial quasi-biennial oscillation (QBO) on the extratropics in a zonally truncated 3D mechanistic stratospheric model. Model results show that the extratropical response to the QBO depends critically on the phase alignment of the QBO with the annual cycle: the signal of extratropical response varies by a factor of 8 between the phase alignment that gives minimum response and that which gives maximum response. Model simulations in which the time and height structure of the QBO are varied suggest that, in this zonally truncated model, the equatorial height of 21–23 km is most influential for the extratropical response and that late autumn/early winter is the time at which the QBO has the most influence over the extratropical circulation. The correlation coefficient between the QBO (measured by zonal wind) and the extratropics (measured by zonal wind or potential temperature) is as high as 0.95. The correlation coefficient is largest for simulations with lower boundary wave forcing weaker than that which gives largest extratropical interannual variability. For stronger extratropical wave forcing, the correlation coefficient is slightly smaller, but the regression coefficient of the linear term in a least squares fit is significantly larger.

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