Evaluation of the Quasi-Biweekly Oscillation over the South China Sea in Early and Late Summer in CAM5

Xu Wang Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, and Joint Center for Global Change Studies, Beijing, China

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Guang J. Zhang Scripps Institution of Oceanography, La Jolla, California, and Ministry of Education Key Laboratory for Earth System Modeling, Department of Earth System Science, Tsinghua University, Beijing, China

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Abstract

Low-frequency intraseasonal oscillations in the tropical atmosphere in general circulation models (GCMs) were studied extensively in many previous studies. However, the simulation of the quasi-biweekly oscillation (QBWO), which is an important component of the intraseasonal oscillations, in GCMs has not received much attention. This paper evaluates the QBWO features over the South China Sea in early [May–June (MJ)] and late [August–September (AS)] summer in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model, version 5.3 (CAM5), using observations and reanalysis data. Results show that the major features of the spatial distribution of the QBWO in both MJ and AS are simulated reasonably well by the model, although the amplitude of the variation is overestimated. CAM5 captures the local oscillation in MJ and the westward propagation in AS of the QBWO. Although there are important biases in geographical location and intensity in MJ, the model represents the QBWO horizontal and vertical structure qualitatively well in AS. The diagnosis of the eddy vorticity budget is conducted to better understand the QBWO activities in the model. Both horizontal advection of relative vorticity and that of planetary vorticity (Coriolis parameter) are important for the local evolution of the QBWO in MJ in observations as well as model simulation, whereas advection of planetary vorticity contributes to the westward propagation of QBWO vorticity anomalies in AS. Since the Coriolis parameter f only changes with latitude, this suggests that the correct simulation of anomalous meridional wind is a key factor in the realistic simulation of the QBWO in the model.

© 2018 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Guang J. Zhang, gzhang@ucsd.edu

Abstract

Low-frequency intraseasonal oscillations in the tropical atmosphere in general circulation models (GCMs) were studied extensively in many previous studies. However, the simulation of the quasi-biweekly oscillation (QBWO), which is an important component of the intraseasonal oscillations, in GCMs has not received much attention. This paper evaluates the QBWO features over the South China Sea in early [May–June (MJ)] and late [August–September (AS)] summer in the National Center for Atmospheric Research (NCAR) Community Atmosphere Model, version 5.3 (CAM5), using observations and reanalysis data. Results show that the major features of the spatial distribution of the QBWO in both MJ and AS are simulated reasonably well by the model, although the amplitude of the variation is overestimated. CAM5 captures the local oscillation in MJ and the westward propagation in AS of the QBWO. Although there are important biases in geographical location and intensity in MJ, the model represents the QBWO horizontal and vertical structure qualitatively well in AS. The diagnosis of the eddy vorticity budget is conducted to better understand the QBWO activities in the model. Both horizontal advection of relative vorticity and that of planetary vorticity (Coriolis parameter) are important for the local evolution of the QBWO in MJ in observations as well as model simulation, whereas advection of planetary vorticity contributes to the westward propagation of QBWO vorticity anomalies in AS. Since the Coriolis parameter f only changes with latitude, this suggests that the correct simulation of anomalous meridional wind is a key factor in the realistic simulation of the QBWO in the model.

© 2018 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Guang J. Zhang, gzhang@ucsd.edu
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  • Bretherton, C. S., and S. Park, 2009: A new moist turbulence parameterization in the Community Atmosphere Model. J. Climate, 22, 34223448, https://doi.org/10.1175/2008JCLI2556.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chan, J. C. L., W. Ai, and J. Xu, 2002: Mechanisms responsible for the maintenance of the 1998 South China Sea summer monsoon. J. Meteor. Soc. Japan, 80, 11031113, https://doi.org/10.2151/jmsj.80.1103.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chatterjee, P., and B. N. Goswami, 2004: Structure, genesis and scale selection of the tropical quasi-biweekly mode. Quart. J. Roy. Meteor. Soc., 130, 11711194, https://doi.org/10.1256/qj.03.133.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, G., and C.-H. Sui, 2010: Characteristics and origin of quasi-biweekly oscillation over the western North Pacific during boreal summer. J. Geophys. Res., 115, D14113, https://doi.org/10.1029/2009JD013389.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, G., and X. Wang, 2017: Effect of the westward-propagating zonal wind anomaly on the initial development of quasi-biweekly oscillation over the South China Sea during early summer. Atmos. Oceanic Sci. Lett., 10, 8995, https://doi.org/10.1080/16742834.2017.1243002.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, T.-C., and J.-M. Chen, 1995: An observational study of the South China Sea monsoon during the 1979 summer: Onset and life cycle. Mon. Wea. Rev., 123, 22952318, https://doi.org/10.1175/1520-0493(1995)123<2295:AOSOTS>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chen, T.-C., M.-C. Yen, and S.-P. Weng, 2000: Interaction between the summer monsoons in East Asia and the South China Sea: Intraseasonal monsoon modes. J. Atmos. Sci., 57, 13731392, https://doi.org/10.1175/1520-0469(2000)057<1373:IBTSMI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cho, H.-R., 1977: Contribution of cumulus cloud life-cycle effects to the large-scale heat and moisture budget equations. J. Atmos. Sci., 34, 8797, https://doi.org/10.1175/1520-0469(1977)034<0087:COCCLC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cho, H.-R., M. A. Jenkins, and J. Boyd, 1983: A first order vorticity equation for tropical easterly waves. J. Atmos. Sci., 40, 958968, https://doi.org/10.1175/1520-0469(1983)040<0958:AFOVEF>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Duchon, C. E., 1979: Lanczos filtering in one and two dimensions. J. Appl. Meteor., 18, 10161022, https://doi.org/10.1175/1520-0450(1979)018<1016:LFIOAT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Fukutomi, Y., and T. Yasunari, 1999: 10–25 day intraseasonal variations of convection and circulation over East Asia and western North Pacific during early summer. J. Meteor. Soc. Japan, 77, 753769, https://doi.org/10.2151/jmsj1965.77.3_753.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hu, W., A. Duan, and B. He, 2017: Evaluation of intra-seasonal oscillation simulations in IPCC AR5 coupled GCMs associated with the Asian summer monsoon. Int. J. Climatol., 37, 476496, https://doi.org/10.1002/joc.5016.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Iacono, M. J., E. J. Mlawer, S. A. Clough, and J.-J. Morcrette, 2000: Impact of an improved longwave radiation model, RRTM, on the energy budget and thermodynamic properties of the NCAR Community Climate Model, CCM3. J. Geophys. Res., 105, 14 87314 890, https://doi.org/10.1029/2000JD900091.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Jia, X., and S. Yang, 2013: Impact of the quasi-biweekly oscillation over the western North Pacific on East Asian subtropical monsoon during early summer. J. Geophys. Res. Atmos., 118, 44214434, https://doi.org/10.1002/jgrd.50422.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kanamitsu, M., W. Ebisuzaki, J. Woollen, S.-K. Yang, J. J. Hnilo, M. Fiorino, and G. L. Potter, 2002: NCEP-DOE AMIP-II Reanalysis (R-2). Bull. Amer. Meteor. Soc., 83, 16311643, https://doi.org/10.1175/BAMS-83-11-1631.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kang, I.-S., and Coauthors, 2002: Intercomparison of the climatological variations of Asian summer monsoon precipitation simulated by 10 GCMs. Climate Dyn., 19, 383395, https://doi.org/10.1007/s00382-002-0245-9.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kemball-Cook, S., and B. Wang, 2001: Equatorial waves and air–sea interaction in the boreal summer intraseasonal oscillation. J. Climate, 14, 29232942, https://doi.org/10.1175/1520-0442(2001)014<2923:EWAASI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Keshavamurty, R. N., 1972: On the vertical tilt of monsoon disturbances. J. Atmos. Sci., 29, 993995, https://doi.org/10.1175/1520-0469(1972)029<0993:OTVTOM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kikuchi, K., and B. Wang, 2009: Global perspective of the quasi-biweekly oscillation. J. Climate, 22, 13401359, https://doi.org/10.1175/2008JCLI2368.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ko, K.-C., and D. G. Vincent, 1995: A composite study of the quasi-periodic subtropical wind maxima over the South Pacific during November 1984–April 1985. J. Climate, 8, 579588, https://doi.org/10.1175/1520-0442(1995)008<0579:ACSOTQ>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ko, K.-C., and D. G. Vincent, 1996: Behavior of one to two week summertime subtropical wind maxima over the South Pacific during ENSO cycle. J. Climate, 9, 516, https://doi.org/10.1175/1520-0442(1996)009<0005:BOOTTW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Krishnamurti, T. N., and H. N. Bhalme, 1976: Oscillations of a monsoon system. Part I. Observational aspects. J. Atmos. Sci., 33, 19371954, https://doi.org/10.1175/1520-0469(1976)033<1937:OOAMSP>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Krishnamurti, T. N., and P. Ardanuy, 1980: The 10 to 20-day westward propagating mode and “Breaks in the Monsoons.” Tellus, 32, 1526, https://doi.org/10.3402/tellusa.v32i1.10476.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kuo, H.-C., J.-H. Chen, R. T. Williams, and C.-P. Chang, 2001: Rossby waves in zonally opposing mean flow: Behavior in northwest Pacific summer monsoon. J. Atmos. Sci., 58, 10351050, https://doi.org/10.1175/1520-0469(2001)058<1035:RWIZOM>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, C., T. Li, A. Lin, D. Gu, and B. Zheng, 2015: Relationship between summer rainfall anomalies and sub-seasonal oscillations in South China. Climate Dyn., 44, 423439, https://doi.org/10.1007/s00382-014-2172-y.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, R. C. Y., and W. Zhou, 2013: Modulation of western North Pacific tropical cyclone activity by the ISO. Part I: Genesis and intensity. J. Climate, 26, 29042918, https://doi.org/10.1175/JCLI-D-12-00210.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, T., and B. Wang, 2005: A review on the western North Pacific monsoon: Synoptic-to-interannual variabilities. Terr. Atmos. Oceanic Sci., 16, 285314, https://doi.org/10.3319/TAO.2005.16.2.285(A).

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Liang, J., L. Wu, X. Ge, and C.-C. Wu, 2011: Monsoonal influence on typhoon Morakot (2009). Part II: Numerical study. J. Atmos. Sci., 68, 22222235, https://doi.org/10.1175/2011JAS3731.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Liebmann, B., 1996: Description of a complete (interpolated) outgoing longwave radiation dataset. Bull. Amer. Meteor. Soc., 77, 12751277.

    • Search Google Scholar
    • Export Citation
  • Lin, J.-L., K. M. Weickman, G. N. Kiladis, B. E. Mapes, S. D. Schubert, M. J. Suarez, J. T. Bacmeister, and M.-I. Lee, 2008: Subseasonal variability associated with Asian summer monsoon simulated by 14 IPCC AR4 coupled GCMs. J. Climate, 21, 45414567, https://doi.org/10.1175/2008JCLI1816.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Liu, H.-B., J. Yang, D.-L. Zhang, and B. Wang, 2014: Roles of synoptic to quasi-biweekly disturbances in generating the summer 2003 heavy rainfall in East China. Mon. Wea. Rev., 142, 886904, https://doi.org/10.1175/MWR-D-13-00055.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Madden, R. A., and P. R. Julian, 1971: Detection of a 40–50-day oscillation in the zonal wind in the tropical Pacific. J. Atmos. Sci., 28, 702708, https://doi.org/10.1175/1520-0469(1971)028<0702:DOADOI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Madden, R. A., and P. R. Julian, 1972: Description of global-scale circulation cells in the tropics with a 40–50-day period. J. Atmos. Sci., 29, 11091123, https://doi.org/10.1175/1520-0469(1972)029<1109:DOGSCC>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mao, J., and J. C. L. Chan, 2005: Intraseasonal variability of the South China Sea summer monsoon. J. Climate, 18, 23882402, https://doi.org/10.1175/JCLI3395.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mao, J., and G. Wu, 2006: Intraseasonal variations of the Yangtze rainfall and its related atmospheric circulation features during the 1991 summer. Climate Dyn., 27, 815830, https://doi.org/10.1007/s00382-006-0164-2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Mlawer, E. J., S. J. Taubman, P. D. Brown, M. J. Iacono, and S. A. Clough, 1997: Radiative transfer for inhomogeneous atmospheres: RRTM, a validated correlated-k model for the longwave. J. Geophys. Res., 102, 16 66316 682, https://doi.org/10.1029/97JD00237.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Morrison, H., and A. Gettelman, 2008: A new two-moment bulk stratiform cloud microphysics scheme in the Community Atmosphere Model, version 3 (CAM3). Part I: Description and numerical tests. J. Climate, 21, 36423659, https://doi.org/10.1175/2008JCLI2105.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Murakami, M., 1976: Analysis of summer monsoon fluctuations over India. J. Meteor. Soc. Japan, 54, 1531, https://doi.org/10.2151/jmsj1965.54.1_15.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Murakami, T., and M. Frydrych, 1974: On the preferred period of upper wind fluctuations during the summer monsoon. J. Atmos. Sci., 31, 15491555, https://doi.org/10.1175/1520-0469(1974)031<1549:OTPPOU>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Neale, R. B., J. H. Richter, and M. Jochum, 2008: The impact of convection on ENSO: From a delayed oscillator to a series of events. J. Climate, 21, 59045924, https://doi.org/10.1175/2008JCLI2244.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Neale, R. B., and Coauthors, 2012: Description of the NCAR Community Atmosphere Model (CAM 5.0). NCAR Tech. Note NCAR/TN-486+STR, 274 pp., www.cesm.ucar.edu/models/cesm1.0/cam/docs/description/cam5_desc.pdf.

  • Park, S., and C. S. Bretherton, 2009: The University of Washington shallow convection and moist turbulence schemes and their impact on climate simulations with the Community Atmosphere Model. J. Climate, 22, 34493469, https://doi.org/10.1175/2008JCLI2557.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Sabeerali, C. T., A. R. Dandi, A. Dhakate, K. Salunke, S. Mahapatra, and S. A. Rao, 2013: Simulation of boreal summer intraseasonal oscillations in the latest CMIP5 coupled GCMs. J. Geophys. Res. Atmos., 118, 44014420, https://doi.org/10.1002/jgrd.50403.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Waliser, D. E., and Coauthors, 2003: AGCM simulations of intraseasonal variability associated with the Asian summer monsoon. Climate Dyn., 21, 423446, https://doi.org/10.1007/s00382-003-0337-1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, B., 1988: Dynamics of tropical low-frequency waves: An analysis of the moist Kelvin wave. J. Atmos. Sci., 45, 20512065, https://doi.org/10.1175/1520-0469(1988)045<2051:DOTLFW>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, B., and T. Li, 1994: Convective interaction with boundary-layer dynamics in the development of a tropical intraseasonal system. J. Atmos. Sci., 51, 13861400, https://doi.org/10.1175/1520-0469(1994)051<1386:CIWBLD>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, B., F. Huang, Z. Wu, J. Yang, X. Fu, and K. Kikuchi, 2009: Multi-scale climate variability of the South China Sea monsoon: A review. Dyn. Atmos. Oceans, 47, 1537, https://doi.org/10.1016/j.dynatmoce.2008.09.004.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, X., and G. Chen, 2017: Quasi-biweekly oscillation over the South China Sea in late summer: Propagation dynamics and energetics. J. Climate, 30, 41034112, https://doi.org/10.1175/JCLI-D-16-0533.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, X., G. Chen, and R. Huang, 2016: Different characteristics of the quasi-biweekly oscillation over the South China Sea in two boreal summer stages. Theor. Appl. Climatol., 126, 113, https://doi.org/10.1007/s00704-015-1550-7.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Webster, P. J., and H.-R. Chang, 1988: Energy accumulation and emanation regions at low latitudes: Impacts of a zonally varying basic state. J. Atmos. Sci., 45, 803829, https://doi.org/10.1175/1520-0469(1988)045<0803:EEAAER>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wu, L., J. Liang, and C.-C. Wu, 2011: Monsoonal influence on Typhoon Morakot (2009). Part I: Observational analysis. J. Atmos. Sci., 68, 22082221, https://doi.org/10.1175/2011JAS3730.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Xu, Z., T. Li, and K. Fan, 2017: The weakened intensity of atmospheric quasi-biweekly oscillation over the western North Pacific during late summer around the late 1990s. J. Climate, 30, 98079826, https://doi.org/10.1175/JCLI-D-16-0759.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, J., B. Wang, B. Wang, and Q. Bao, 2010: Biweekly and 21–30-day variations of the subtropical summer monsoon rainfall over the lower reach of the Yangtze River basin. J. Climate, 23, 11461159, https://doi.org/10.1175/2009JCLI3005.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yang, J., Q. Bao, B. Wang, D.-Y. Gong, H. He, and M.-N. Gao, 2014: Distinct quasi-biweekly features of the subtropical East Asian monsoon during early and late summers. Climate Dyn., 42, 14691486, https://doi.org/10.1007/s00382-013-1728-6.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhang, G. J., and N. A. McFarlane, 1995: Sensitivity of climate simulations to the parameterization of cumulus convection in the Canadian Climate Centre general circulation model. Atmos.–Ocean, 33, 407446, https://doi.org/10.1080/07055900.1995.9649539.

    • Crossref
    • Search Google Scholar
    • Export Citation
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