• Bajuk, L. J., and C. B. Leovy, 1998a: Are there real interdecadal variations in marine low clouds? J. Climate, 11 , 29102921.

  • Bajuk, L. J., and C. B. Leovy, 1998b: Seasonal and interannual variations in stratiform and convective clouds over the tropical Pacific and Indian Oceans from ship observations. J. Climate, 11 , 29222941.

    • Search Google Scholar
    • Export Citation
  • Barkstrom, B. R., 1984: The Earth Radiation Budget Experiment (ERBE). Bull. Amer. Meteor. Soc, 65 , 11701185.

  • Bretherton, C. S., 1992: A conceptual model of the stratocumulus-trade-cumulus transition in the subtropical oceans. Proc. 11th Int. Conf. on Clouds and Precipitation, Vol. 1, Montreal, QC, Canada, International Commission on Clouds and Precipitation and International Association of Meteorology and Atmospheric Physics, 374–377.

    • Search Google Scholar
    • Export Citation
  • Bretherton, C. S., and M. C. Wyant, 1997: Moisture transport, lower-tropospheric stability, and decoupling of cloud-topped boundary layers. J. Atmos. Sci, 54 , 148167.

    • Search Google Scholar
    • Export Citation
  • Bretherton, C. S., C. Smith, and J. M. Wallace, 1992: An intercomparison of methods for finding coupled patterns in climate data. J. Climate, 5 , 541560.

    • Search Google Scholar
    • Export Citation
  • Deser, C. D., and J. M. Wallace, 1990: Large-scale atmospheric circulation features of warm and cold episodes in the tropical Pacific. J. Climate, 3 , 12541281.

    • Search Google Scholar
    • Export Citation
  • Deser, C. D., J. J. Bates, and S. Wahl, 1993: The influence of sea surface temperature gradients on stratiform cloudiness along the equatorial front in the Pacific Ocean. J. Climate, 6 , 11721180.

    • Search Google Scholar
    • Export Citation
  • Hahn, C. J., and S. G. Warren, 1999: Extended edited synoptic cloud reports from ships and land stations over the globe, 1952–1996. Rep. NDP026C, Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, TN, 71 pp. [Available from Data Support Section, National Center for Atmospheric Research, Boulder, CO 80307-3000.].

    • Search Google Scholar
    • Export Citation
  • Hahn, C. J., S. G. Warren, and J. London, 1995: The effect of moonlight on observation of cloud cover at night, and application to cloud climatology. J. Climate, 8 , 14291446.

    • Search Google Scholar
    • Export Citation
  • Harrison, E. F., P. Minnis, B. R. Barkstrom, V. Ramanathan, R. D. Cess, and G. G. Gibson, 1990: Seasonal variation of cloud radiative forcing derived from the Earth Radiation Budget Experiment. J. Geophys. Res, 95 , 1868718703.

    • Search Google Scholar
    • Export Citation
  • Kalnay, E., and Coauthors, 1996: The NCEP/NCAR 40-Year Reanalysis Project. Bull. Amer. Meteor. Soc, 77 , 437471.

  • Klein, S. A., 1997: Synoptic variability of low-cloud properties and meteorological parameters in the subtropical trade wind boundary layer. J. Climate, 10 , 20182039.

    • Search Google Scholar
    • Export Citation
  • Klein, S. A., and D. L. Hartmann, 1993: The seasonal cycle of low stratiform clouds. J. Climate, 6 , 15871605.

  • Klein, S. A., D. L. Hartmann, and J. R. Norris, 1995: On the relationships among low-cloud structure, sea surface temperature, and atmospheric circulation in the summertime northeast Pacific. J. Climate, 8 , 11401155.

    • Search Google Scholar
    • Export Citation
  • Klein, S. A., B. J. Soden, and N. C. Lau, 1999: Remote sea surface temperature variations during ENSO: Evidence for a tropical atmospheric bridge. J. Climate, 12 , 917932.

    • Search Google Scholar
    • Export Citation
  • Leith, C. E., 1973: The standard errors of time-average estimates of climatic means. J. Appl. Meteor, 12 , 10661069.

  • Mitchell, T. P., and J. M. Wallace, 1992: The annual cycle in equatorial convection and sea surface temperature. J. Climate, 5 , 11401156.

    • Search Google Scholar
    • Export Citation
  • Norris, J. R., 1998: Low cloud type over the ocean from surface observations. Part I: Relationship to surface meteorology and the vertical distribution of temperature and moisture. J. Climate, 11 , 369382.

    • Search Google Scholar
    • Export Citation
  • Norris, J. R., 2000: Interannual and interdecadal variability in the storm track, cloudiness, and sea surface temperature over the summertime North Pacific. J. Climate, 13 , 422430.

    • Search Google Scholar
    • Export Citation
  • Norris, J. R., and C. B. Leovy, 1994: Interannual variability in stratiform cloudiness and sea surface temperature. J. Climate, 7 , 19151925.

    • Search Google Scholar
    • Export Citation
  • Norris, J. R., and S. A. Klein, 2000: Low cloud type over the ocean from surface observations. Part III: Relationship to vertical motion and the regional surface synoptic environment. J. Climate, 13 , 245256.

    • Search Google Scholar
    • Export Citation
  • North, G. R., T. L. Bell, R. F. Cahalan, and F. J. Moeng, 1982: Sampling errors in the estimation of empirical orthogonal functions. Mon. Wea. Rev, 110 , 699706.

    • Search Google Scholar
    • Export Citation
  • Park, S., 2004: Remote ENSO influence on Mediterranean sky conditions during late summer and autumn: Evidence for a slowly evolving atmospheric bridge. Quart. J. Roy. Meteor. Soc., in press.

    • Search Google Scholar
    • Export Citation
  • Ramage, C. S., 1984: Can shipboard measurements reveal secular changes in tropical air–sea heat flux? J. Appl. Meteor, 23 , 187193.

  • Ramage, C. S., 1987: Secular change in reported surface wind speeds over the ocean. J. Appl. Meteor, 26 , 525528.

  • Ramanathan, V., R. D. Cess, E. F. Harrison, P. Minnis, B. R. Barkstrom, E. Ahmed, and D. L. Hartmann, 1989: Cloud–radiative forcing and climate: Results from the Earth Radiation Budget Experiment. Science, 243 , 5763.

    • Search Google Scholar
    • Export Citation
  • Reed, R. K., 1977: On estimating insolation over the ocean. J. Phys. Oceanogr, 7 , 482485.

  • Ropelewski, C. F., and M. S. Halpert, 1987: Global and regional scale precipitation patterns associated with the El Niño/Southern Oscillation. Mon. Wea. Rev, 115 , 16061626.

    • Search Google Scholar
    • Export Citation
  • Slingo, A. J., 1990: Sensitivity of the Earth's radiation budget to changes in low clouds. Nature, 343 , 4950.

  • Wallace, J. M., and D. S. Gutzler, 1981: Teleconnections in the geopotential height field during the Northern Hemisphere winter. Mon. Wea. Rev, 109 , 784812.

    • Search Google Scholar
    • Export Citation
  • WMO, 1975: Manual on the observation of clouds and other meteors: Volume 1. WMO Publication 407, 155 pp.

  • Wright, P. B., 1986: Problems in the use of ship observations for the study of interdecadal climate changes. Mon. Wea. Rev, 114 , 10281034.

    • Search Google Scholar
    • Export Citation
  • Zhang, Y., J. M. Wallace, and D. S. Battisti, 1997: ENSO-like interdecadal variability: 1900–93. J. Climate, 10 , 10041020.

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 374 137 15
PDF Downloads 241 91 8

Marine Low-Cloud Anomalies Associated with ENSO

Sungsu ParkDepartment of Atmospheric Sciences, University of Washington, Seattle, Washington

Search for other papers by Sungsu Park in
Current site
Google Scholar
PubMed
Close
and
Conway B. LeovyDepartment of Atmospheric Sciences, University of Washington, Seattle, Washington

Search for other papers by Conway B. Leovy in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

As a contribution to understanding the possible impact of altered climate regimes on marine clouds, and hence on cloud radiative forcing, ship-observed marine low clouds and precipitation frequency for individual seasons are regressed at zero lag on an index of El Niño–Southern Oscillation (ENSO) for the period December 1955– January 1996 for ocean areas between 40°S and 70°N. Seasonal anomalies of atmospheric circulation parameters, static stability, and SST are also examined in order to illuminate physical mechanisms responsible for observed ENSO cloud variations.

The following extratropical regions exhibit significant ENSO cloud anomalies and are discussed in detail: winter–spring North Pacific, summer North Pacific, winter western North Atlantic, autumn northeastern Atlantic, and western Mediterranean Sea. In all of these regions except the summer North Pacific, cloud anomalies are related to jet stream and storm track anomalies associated with atmospheric teleconnection patterns. The summer North Pacific anomalies are also connected with jet stream and storm track anomalies, but these are associated with a persistent SST anomaly rather than an atmospheric teleconnection. ENSO anomalies in the western and eastern equatorial Pacific are analyzed in greater detail than in previous work, as well as those in the Arabian Sea during winter and summer monsoons. With the exception of the Arabian Sea region in winter, cloud anomalies are consistently related to 1) changes in storm tracks and/or 2) changes in low-level static stability and temperature advection.

Corresponding author address: Sungsu Park, Advanced Study Program, NCAR, 1850 Table Mesa Dr., P.O. Box 3000, Boulder, CO 80307. Email: sungsup@ucar.edu

Abstract

As a contribution to understanding the possible impact of altered climate regimes on marine clouds, and hence on cloud radiative forcing, ship-observed marine low clouds and precipitation frequency for individual seasons are regressed at zero lag on an index of El Niño–Southern Oscillation (ENSO) for the period December 1955– January 1996 for ocean areas between 40°S and 70°N. Seasonal anomalies of atmospheric circulation parameters, static stability, and SST are also examined in order to illuminate physical mechanisms responsible for observed ENSO cloud variations.

The following extratropical regions exhibit significant ENSO cloud anomalies and are discussed in detail: winter–spring North Pacific, summer North Pacific, winter western North Atlantic, autumn northeastern Atlantic, and western Mediterranean Sea. In all of these regions except the summer North Pacific, cloud anomalies are related to jet stream and storm track anomalies associated with atmospheric teleconnection patterns. The summer North Pacific anomalies are also connected with jet stream and storm track anomalies, but these are associated with a persistent SST anomaly rather than an atmospheric teleconnection. ENSO anomalies in the western and eastern equatorial Pacific are analyzed in greater detail than in previous work, as well as those in the Arabian Sea during winter and summer monsoons. With the exception of the Arabian Sea region in winter, cloud anomalies are consistently related to 1) changes in storm tracks and/or 2) changes in low-level static stability and temperature advection.

Corresponding author address: Sungsu Park, Advanced Study Program, NCAR, 1850 Table Mesa Dr., P.O. Box 3000, Boulder, CO 80307. Email: sungsup@ucar.edu

Save