Past projects





My links

CPT webpage

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Contact me:
Cecile Hannay

Past projects

CPT liaison

I was the NCAR liaison for the Climate Process Team (CPT) on Low-Latitude Cloud Feedbacks on Climate Sensitivity. This was a multi-institution NSF/NOAA-sponsored project (10/03-9/06) to try to better understand the differences in cloud feedbacks on climate sensitivity in three leading US climate models (NCAR, GFDL, and NASA-GMAO), and to use recent findings from observations and process models to reduce uncertainties in climate sensitivity by improving the representation of cloud microphysics, turbulence and moist convection, and radiative transfer in cloudy atmospheres in these models.

CPT columns

Comparison of the NCAR and GFDL models in subsidence regions


Subgrid scale cloud variability: subcolumn generator and McICA method implementation

    To take into account the subgrid scale cloud variability in CAM, we have implemented a subcolumn column generator. The idea of the cloud generator is that the Subgrid scale cloud variability can be represented by a set of subcolumns that are generated randomly.
    We are testing the subcolumn generator on radiation calculations using the Monte Carlo Independant Column Approximation (McICA). The McICA is a method developed to improve the treatment of cloud variability in climate models. This method is essentially a sampling strategy that yields unbiased estimates of heating rate profiles with respect to the full ICA, but that speeds the calculation up compared to the full ICA.


Last modified: Jan 8 2010   by