• Barker, H. W., , and Li Z. , 1995: Improved simulation of clear-sky shortwave radiative transfer in the CCC-GCM. J. Climate, 8 , 22132223.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Baum, B. A., , and Trepte Q. , 1999: A grouped threshold approach for scene identification in AVHRR imagery. J. Atmos. Oceanic Technol., 16 , 793800.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Berbery, E. H., , Mitchell K. E. , , Benjamin S. , , Smirnova T. , , Richie H. , , Hogue R. , , and Radeva E. , 1999: Assessment of land-surface energy budgets from regional and global models. J. Geophys. Res., 104 , 1932919348.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bleck, R., , and Benjamin S. G. , 1993: Regional weather prediction with a model combining terrain-following and isentropic coordinates. Part I: Model description. Mon. Wea. Rev., 121 , 17701785.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Brasnett, B., 1999: A global analysis of snow depth for numerical weather prediction. J. Appl. Meteor., 38 , 726740.

  • Brooks, D. R., , Harrison E. F. , , Minnis P. , , and Suttles J. T. , 1986: Development of algorithms for understanding the temporal and spatial variability of the earth's radiation balance. Rev. Geophys., 24 , 422438.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Bussières, N., 2002: Thermal features of the Mackenzie River Basin from NOAA AVHRR observations for summer 1994. Atmos.–Ocean, 40 , 233244.

  • Cote, J., , Gravel S. , , Methot A. , , Patoine A. , , Roch M. , , and Staniforth A. , 1998: The operational CMC–MRB Global Environmental Multiscale (GEM) Model. Part I: Design considerations and formulation. Mon. Wea. Rev., 126 , 13731395.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Duvel, J-P., and Coauthors. 2001: The ScaRaB–Resurs earth radiation budget dataset and first results. Bull. Amer. Meteor. Soc., 82 , 13971408.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feng, J., , Leighton H. G. , , Mackay M. D. , , Bussières N. , , Hollmann R. , , and Stuhlmann R. , 2002: A comparison of solar radiation budgets in the Mackenzie River Basin from satellite measurements and a regional climate model. Atmos.–Ocean, 40 , 221232.

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

  • Li, Z., , Leighton H. G. , , Masuda K. , , and Takashima T. , 1993: Estimation of SW flux absorbed at the surface from TOA reflected flux. J. Climate, 6 , 317330.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • MacKay, M. D., , Seglenieks F. , , Verseghy D. , , Soulis E. D. , , Snelgrove K. R. , , Walker A. , , and Szeto K. , 2003: Modeling Mackenzie basin surface water balance during CAGES with the Canadian Regional Climate Model. J. Hydrometeor., 4 , 748767.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Marsh, P., and Coauthors. 1999: Snow cover melt and runoff in boreal and tundra ecosystems. Proc. Fifth Scientific Workshop for the Mackenzie GEWEX Study (MAGS), Edmonton, AB, Canada, GEWEX, 45–50.

    • Search Google Scholar
    • Export Citation
  • McFarlane, N. A., , Boer G. J. , , Blanchet J-P. , , and Lazare M. , 1992: The Canadian Climate Centre second generation general circulation model and its equilibrium climate. J. Climate, 5 , 10131044.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rao, C. R. N., , and Chen J. , 1999: Revised post-launch calibration of the visible and near-infrared channels of the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-14 spacecraft. Int. J. Remote Sens., 20 , 34853491.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Roads, J., and Coauthors. 2003: GCIP Water and Energy Budget Synthesis (WEBS). J. Geophys. Res., in press.

  • Rogers, E., , Black T. L. , , Deaven D. G. , , DiMego G. J. , , Zhao Q. , , Baldwin M. , , Junker N. W. , , and Lin Y. , 1996: Changes to the operational “early” eta analysis/forecast system at the National Centers for Environmental Prediction. Wea. Forecasting, 11 , 391413.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Rouse, W. R., , Blanken P. D. , , Eaton A. K. , , and Spence C. , 1999: Energy and water balance of high latitudes. Proc. Fifth Scientific Workshop for the Mackenzie GEWEX Study (MAGS), Edmonton, AB, Canada, GEWEX, 80–86.

    • Search Google Scholar
    • Export Citation
  • Schertzer, W. M., , Rouse W. R. , , and Blanken P. D. , 1999: Annual heat content of Great Slave Lake. Proc. Fifth Scientific Workshop for the Mackenzie GEWEX Study (MAGS), Edmonton, AB, Canada, GEWEX, 87–92.

    • Search Google Scholar
    • Export Citation
  • Stewart, R. E., and Coauthors. 1998: The Mackenzie GEWEX Study: The water and energy cycles of a major North American river basin. Bull. Amer. Meteor. Soc., 79 , 26652684.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Suttles, J. T., and Coauthors. 1988: Shortwave Radiation. Vol. 1, Angular Radiation Models for Earth–Atmosphere System, NASA Reference Publication 1184, 144 pp.

    • Search Google Scholar
    • Export Citation
  • Tahnk, W. R., , and Coakley J. A. Jr., 2002: Improved calibration coefficients for NOAA-12 and NOAA-15 AVHRR visible and near-IR channels. J. Atmos. Oceanic Technol., 19 , 18261833.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Verseghy, D. L., 1991: CLASS-A Canadian land surface scheme for GCMs. Part I: Soil model. Int. J. Climatol., 11 , 111133.

  • Verseghy, D. L., , McFarland N. A. , , and Lazare M. , 1993: CLASS-A Canadian land surface scheme for GCMs. Part II: Vegetation model and coupled runs. Int. J. Climatol., 13 , 347370.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yin, Y., , Gong P. , , and Cohen S. , 1994: An integrated data base for Mackenzie River Basin climate change impact assessment. Can. J. Remote Sens., 20 , 426434.

    • Crossref
    • Search Google Scholar
    • Export Citation
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Radiation Budgets in the Mackenzie River Basin: Retrieval from Satellite Observations and an Evaluation of the Canadian Regional Climate Model

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  • 1 Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, Canada
  • | 2 Meteorological Service of Canada, Downsview, Ontario, Canada
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Abstract

The Canadian Global Energy and Water Cycle Experiment (GEWEX) Enhanced Study (CAGES) was a 14-month period in 1998–99 during which there were enhanced measurements of water vapor, precipitation, snow cover, radiation, snowmelt, evaporation, stream discharge, and other variables in the Mackenzie River basin (MRB). These measurements provided the initialization and validation fields for modeling and remote sensing studies. During the CAGES period there were only limited broadband satellite observations of radiation fluxes over the MRB from the second flight module of the Scanner for Radiation Budget (ScaRaB) instrument. A more extensive dataset of solar radiation fluxes at the top of the atmosphere (TOA) and at the surface was derived for CAGES from the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) observations. The derived solar radiation fluxes at the surface were evaluated against the surface measurements in the basin. The results show that mean differences are generally less than 10 W m−2 at each site.

Solar fluxes at the TOA and at the surface, and longwave (LW) fluxes at the TOA from the Canadian Regional Climate Model (CRCM) are compared with those from satellite measurements and retrievals. It is found that the CRCM overestimated the TOA reflected solar flux consistently by an average of 33 W m−2 during summer months, while during months when the surface is mainly covered by snow, the CRCM agrees with satellite retrievals well, with a mean difference of 2.1 W m−2. The differences in the basin monthly mean atmospheric absorption between the CRCM and the satellite retrievals for 9 months during the CAGES period vary from −11 to 12 W m−2. The overestimation of the TOA-reflected fluxes in the model during the summer months is mainly at the expense of an underestimation of the net surface solar fluxes. A comparison of cloud amount from the CRCM and the satellite retrievals shows an overprediction by the CRCM, which is responsible for the overestimation of the TOA-reflected flux during the summer months. A comparison of outgoing LW flux from the CRCM with satellite measurements in winter months during the CAGES period shows the CRCM fluxes to be 6–12 W m−2 less than the measured fluxes, which is at least partly due to the underestimation of surface temperature in the model.

Corresponding author address: Dr. Henry Leighton, Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada. Email: henry.leighton@mcgill.ca

Abstract

The Canadian Global Energy and Water Cycle Experiment (GEWEX) Enhanced Study (CAGES) was a 14-month period in 1998–99 during which there were enhanced measurements of water vapor, precipitation, snow cover, radiation, snowmelt, evaporation, stream discharge, and other variables in the Mackenzie River basin (MRB). These measurements provided the initialization and validation fields for modeling and remote sensing studies. During the CAGES period there were only limited broadband satellite observations of radiation fluxes over the MRB from the second flight module of the Scanner for Radiation Budget (ScaRaB) instrument. A more extensive dataset of solar radiation fluxes at the top of the atmosphere (TOA) and at the surface was derived for CAGES from the National Oceanic and Atmospheric Administration (NOAA) Advanced Very High Resolution Radiometer (AVHRR) observations. The derived solar radiation fluxes at the surface were evaluated against the surface measurements in the basin. The results show that mean differences are generally less than 10 W m−2 at each site.

Solar fluxes at the TOA and at the surface, and longwave (LW) fluxes at the TOA from the Canadian Regional Climate Model (CRCM) are compared with those from satellite measurements and retrievals. It is found that the CRCM overestimated the TOA reflected solar flux consistently by an average of 33 W m−2 during summer months, while during months when the surface is mainly covered by snow, the CRCM agrees with satellite retrievals well, with a mean difference of 2.1 W m−2. The differences in the basin monthly mean atmospheric absorption between the CRCM and the satellite retrievals for 9 months during the CAGES period vary from −11 to 12 W m−2. The overestimation of the TOA-reflected fluxes in the model during the summer months is mainly at the expense of an underestimation of the net surface solar fluxes. A comparison of cloud amount from the CRCM and the satellite retrievals shows an overprediction by the CRCM, which is responsible for the overestimation of the TOA-reflected flux during the summer months. A comparison of outgoing LW flux from the CRCM with satellite measurements in winter months during the CAGES period shows the CRCM fluxes to be 6–12 W m−2 less than the measured fluxes, which is at least partly due to the underestimation of surface temperature in the model.

Corresponding author address: Dr. Henry Leighton, Department of Atmospheric and Oceanic Sciences, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada. Email: henry.leighton@mcgill.ca

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