Séminaire vendredi 20 octobre 11h00 / Seminar Friday Oct. 20, 11:00 AM

 Conférencier/Lecturer: Jason Cole
                        (ARMP, Downsview)

        Sujet/Subject:  Parameterizing the interaction between radiation
                        and clouds in dynamical models

          Presentation: Anglais / English

             Lieu/Room: Grande salle du premier étage CMC

                  iweb: http://iweb.cmc.ec.gc.ca/rpn/SEM

          web: http://collaboration.cmc.ec.gc.ca/science/rpn/SEM/index.php

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                         RESUME / ABSTRACT

This seminar briefly discusses some issues related to parameterizing the
interaction between clouds and radiation in large and small-scale
dynamical models.  To illustrate these issues, results from three sets of
numerical experiments will be presented.  Results from the Monte Carlo
Independent Column Approximation (McICA) model intercomparison will be
presented as an example of parameterizing radiative transfer in
conventional global climate models (GCMs).  A review of results from
experiments with small-scale dynamical models will be presented to discuss
the possible impact of using one-dimensional radiative transfer rather
than three-dimensional radiative transfer in these models.  Offline
radiative transfer calculations suggest that differences in radiative
fluxes between these two radiative transfer methods can be significant in
highly resolved cloud models.  Finally, results from numerical experiments
performed using the Multiscale-Modelling Framework (MMF) will be presented.
The MMF is a GCM that uses two-dimensional cloud system resolving models
instead of conventional parameterizations.  This allows us to examine
potential impacts of excluding small-scale cloud-radiation interactions,
as is done in conventional GCMs, on season-long simulations.