Critical Evaluation of the ISCCP Simulator Using Ground-Based Remote Sensing Data

Gerald G. Mace Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah

Search for other papers by Gerald G. Mace in
Current site
Google Scholar
PubMed
Close
,
Stephanie Houser Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah

Search for other papers by Stephanie Houser in
Current site
Google Scholar
PubMed
Close
,
Sally Benson Department of Atmospheric Sciences, University of Utah, Salt Lake City, Utah

Search for other papers by Sally Benson in
Current site
Google Scholar
PubMed
Close
,
Stephen A. Klein Program for Climate Model Diagnosis and Intercomparison, Lawrence Livermore National Laboratory, Livermore, California

Search for other papers by Stephen A. Klein in
Current site
Google Scholar
PubMed
Close
, and
Qilong Min Atmospheric Sciences Research Center, University at Albany, State University of New York, Albany, New York

Search for other papers by Qilong Min in
Current site
Google Scholar
PubMed
Close
Restricted access

Abstract

Given the known shortcomings in representing clouds in global climate models (GCMs), comparisons with observations are critical. The International Satellite Cloud Climatology Project (ISCCP) diagnostic products provide global descriptions of cloud-top pressure and column optical depth that extend over multiple decades. Given the characteristics of the ISCCP product, the model output must be converted into what the ISCCP algorithm would diagnose from an atmospheric column with similar physical characteristics. This study evaluates one component of this so-called ISCCP simulator by comparing ISCCP results with simulated ISCCP diagnostics that are derived from data collected at the Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) Climate Research Facility. It is shown that if a model were to simulate the cloud radiative profile with the same accuracy as can be derived from the ARM data, the likelihood of that occurrence being classified with similar cloud-top pressure and optical depth as ISCCP would range from 30% to 70% depending on optical depth. The ISCCP simulator improved the agreement of cloud-top pressure between ground-based remote sensors and satellite observations, and we find only minor discrepancies because of the parameterization of cloud-top pressure in the ISCCP simulator. The differences seem to be primarily due to discrepancies between satellite and ground-based sensors in the visible optical depth. The source of the optical depth bias appears to be due to subpixel cloud field variability in the retrieval of optical depths from satellite sensors. These comparisons suggest that caution should be applied to comparisons between models and ISCCP observations until the differences in visible optical depths are fully understood. The simultaneous use of ground-based and satellite retrievals in the evaluation of model clouds is encouraged.

Corresponding author address: Gerald G. Mace, Department of Meteorology, University of Utah, 135 South 1460 East, Room 819 (WBB), Salt Lake City, UT 84112-0110. Email: jay.mace@utah.edu

Abstract

Given the known shortcomings in representing clouds in global climate models (GCMs), comparisons with observations are critical. The International Satellite Cloud Climatology Project (ISCCP) diagnostic products provide global descriptions of cloud-top pressure and column optical depth that extend over multiple decades. Given the characteristics of the ISCCP product, the model output must be converted into what the ISCCP algorithm would diagnose from an atmospheric column with similar physical characteristics. This study evaluates one component of this so-called ISCCP simulator by comparing ISCCP results with simulated ISCCP diagnostics that are derived from data collected at the Atmospheric Radiation Measurement Program (ARM) Southern Great Plains (SGP) Climate Research Facility. It is shown that if a model were to simulate the cloud radiative profile with the same accuracy as can be derived from the ARM data, the likelihood of that occurrence being classified with similar cloud-top pressure and optical depth as ISCCP would range from 30% to 70% depending on optical depth. The ISCCP simulator improved the agreement of cloud-top pressure between ground-based remote sensors and satellite observations, and we find only minor discrepancies because of the parameterization of cloud-top pressure in the ISCCP simulator. The differences seem to be primarily due to discrepancies between satellite and ground-based sensors in the visible optical depth. The source of the optical depth bias appears to be due to subpixel cloud field variability in the retrieval of optical depths from satellite sensors. These comparisons suggest that caution should be applied to comparisons between models and ISCCP observations until the differences in visible optical depths are fully understood. The simultaneous use of ground-based and satellite retrievals in the evaluation of model clouds is encouraged.

Corresponding author address: Gerald G. Mace, Department of Meteorology, University of Utah, 135 South 1460 East, Room 819 (WBB), Salt Lake City, UT 84112-0110. Email: jay.mace@utah.edu

Save
  • Ackerman, T. P., and G. M. Stokes, 2003: The Atmospheric Radiation Measurement Program. Phys. Today, 56 , 3845.

  • Barker, H. W., T. J. Curtis, E. Leontieva, and K. Stamnes, 1998: Optical depth of overcast cloud across Canada: Estimates based on surface pyranometer and satellite measurements. J. Climate, 11 , 29082994.

    • Search Google Scholar
    • Export Citation
  • Berk, A., L. S. Bernstein, and D. C. Robertson, 1989: MODTRAN: A moderate resolution model for LOWTRAN 7. Spectral Sciences, Inc. Final Rep., Geophysics Laboratory Rep. GL-TR-89-0122, 44 pp.

    • Search Google Scholar
    • Export Citation
  • Cahalan, R. F., W. Ridgway, W. J. Wiscombe, T. L. Bell, and J. B. Snider, 1994: The albedo of fractal stratocumulus clouds. J. Atmos. Sci., 51 , 24342455.

    • Search Google Scholar
    • Export Citation
  • Davis, A., A. Marshak, R. Cahalan, and W. Wiscombe, 1997: The Landsat scale break in stratocumulus as a three-dimensional radiative transfer effect: Implications for cloud remote sensing. J. Atmos. Sci., 54 , 241260.

    • Search Google Scholar
    • Export Citation
  • Dufresne, J.-L., and S. Bony, 2008: An assessment of the primary sources of spread of global warming estimates from coupled ocean–atmosphere models. J. Climate, 21 , 51355144.

    • Search Google Scholar
    • Export Citation
  • Kato, S., and A. Marshak, 2009: Solar zenith and viewing geometry-dependent errors in satellite retrieved cloud optical thickness: Marine stratocumulus. J. Geophys. Res., 114 , D01202. doi:10.1029/2008JD010579.

    • Search Google Scholar
    • Export Citation
  • Klein, S. A., and C. Jakob, 1999: Validation and sensitivities of frontal clouds simulated by the ECMWF model. Mon. Wea. Rev., 127 , 25142531.

    • Search Google Scholar
    • Export Citation
  • Mace, G. G., and S. Benson, 2008: The vertical structure of cloud occurrence and radiative forcing at the SGP ARM site as revealed by 8 years of continuous data. J. Climate, 21 , 25912610.

    • Search Google Scholar
    • Export Citation
  • Mace, G. G., and Coauthors, 2006: Cloud radiative forcing at the Atmospheric Radiation Measurement Program Climate Research Facility: 1. Technique, validation, and comparison to satellite-derived diagnostic quantities. J. Geophys. Res., 111 , D11S90. doi:10.1029/2005JD005921.

    • Search Google Scholar
    • Export Citation
  • Min, Q., and L. C. Harrison, 1996: Cloud properties derived from surface MFRSR measurements and comparison with GOES results at the ARM SGP site. Geophys. Res. Lett., 23 , 16411644.

    • Search Google Scholar
    • Export Citation
  • Minnis, P., W. L. Smith Jr., D. P. Garber, J. K. Ayers, and D. R. Doelling, 1995: Cloud properties derived from GOES-7 for the spring 1994 ARM intensive observing period using version 1.0.0 of the ARM Satellite Data Analysis Program. NASA Reference Publ. 1366, 59 pp.

    • Search Google Scholar
    • Export Citation
  • Pincus, R., M. Szczodrak, J. Gu, and P. Austin, 1995: Uncertainty in cloud optical depth estimates from satellite radiance measurements. J. Climate, 8 , 14531462.

    • Search Google Scholar
    • Export Citation
  • Randall, D., M. Khairoutdinov, A. Arakawa, and W. Grabowski, 2003: Breaking the cloud parameterization deadlock. Bull. Amer. Meteor. Soc., 11 , 15471564.

    • Search Google Scholar
    • Export Citation
  • Rossow, W. B., A. W. Walker, D. E. Beuschel, and M. D. Roiter, 1996: International Satellite Cloud Climatology Project (ISCCP) documentation of new cloud datasets. WMO Rep. WMO/TD 737, 115 pp.

    • Search Google Scholar
    • Export Citation
  • Schiffer, R. A., and W. B. Rossow, 1983: The International Satellite Cloud Climatology Project (ISCCP): The first project of the World Climate Research Programme. Bull. Amer. Meteor. Soc., 64 , 779784.

    • Search Google Scholar
    • Export Citation
  • Soden, B. J., and I. M. Held, 2006: An assessment of climate feedbacks in coupled ocean–atmosphere models. J. Climate, 19 , 33543360.

    • Search Google Scholar
    • Export Citation
  • Solomon, S., D. Qin, M. Manning, M. Marquis, K. Averyt, M. M. B. Tignor, H. L. Miller Jr., and Z. Chen, Eds. 2007: Climate Change 2007: The Physical Science Basis. Cambridge University Press, 996 pp.

    • Search Google Scholar
    • Export Citation
  • Webb, M., C. Senior, S. Bony, and J.-J. Morcrette, 2001: Combining ERBE and ISCCP data to assess clouds in the Hadley Centre, ECMWF and LMD atmospheric climate models. Climate Dyn., 17 , 905922.

    • Search Google Scholar
    • Export Citation
  • Williams, K. D., and G. Tselioudis, 2007: GCM intercomparison of global cloud regimes: Present-day evaluation and climate change response. J. Climate Dyn., 29 , 231250.

    • Search Google Scholar
    • Export Citation
  • Williams, K. D., and M. J. Webb, 2009: A quantitative performance assessment of cloud regimes in climate models. Climate Dyn., 33 , 141157. doi:10.1007/s00382-008-0443-1.

    • Search Google Scholar
    • Export Citation
  • Zhang, M. H., and Coauthors, 2005: Comparing clouds and their seasonal variations in 10 atmospheric general circulation models with satellite measurements. J. Geophys. Res., 110 , D15S02. doi:10.1029/2004jd005021.

    • Search Google Scholar
    • Export Citation
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 398 118 9
PDF Downloads 141 64 5