Evaluation of cloud hydrometers from Korean Integrated Model (KIM) using
multi reanalysis products and satellite observations
Abstract
Validation of cloud hydrometeors simulation from the global models is
important issue as it pertains to the accuracy of climate predictions.
In this study, the cloud hydrometeor data from Korean Integrated Model
(KIM) is validated using different Reanalysis (ERAI, ERA5, and MERRA)
and Satellite Observations (Cloudsat). In ERA5 products, cloud snow
water and rain water are also available. Satellite observations are
gridded to compare with model simulations. Cloud liquid water (Qc),
Cloud snow water (Qs), Cloud ice water (Qi), Cloud rain water (Qr),
Vapour mixing ratio (Qv) for January (dry) and July (wet seasons) of
2017 are considered for validation. BIAS and RMSE are calculated for
comparison. To understand the vertical distribution of hydrometeors,
contour frequency altitude diagrams (CFADs) are plotted. Early
validation of KIM hydrometeors shows the reasonable estimate of
different hydrometeors with KIM model showing more Qc at surface, more
Qv at upper levels. The vertical structure of Qi has showed significant
bias at upper levels with model showing large ice values at higher
levels. ERAI and ERA5 products has showed distinct pattern of Qi due to
different configurations. More Qs at upper levels is also evident in
model simulations. Combined distribution (Qc+Qi) of KIM at lower (upper)
levels is more comparable with ERA5 (MERRA) products. Further, Qr
distribution shows underestimation at the equator and over estimation at
the latitude belts. To examine the contribution of different physics
modules related to the bias, the hydrometeors from cumulus, microphysics
and shallow convection are also analyzed separately. Accuracy of KIM
simulated cloud hydrometeors against different products and possible
causes for biases will be discussed in the conference.