A Japanese community climate model, called Model for
Interdisciplinary Research on Climate (MIROC), has been developed for
use of various aspects of climate research. We are currently under
operation of MIROC with three types of configuration: a high-resolution
climate model for the decadal climate prediction, a low-resolution
Earth system model, and a low-resolution new version of the climate
model (MIROC5). In this talk, I would like to introduce outcomes from
MIROC5, in which many of the atmospheric parameterization schemes have
been updated. Improvements in the climate simulation with MIROC5 and a
high sensitivity of the ENSO simulation to a perturbation in the
cumulus convection scheme are presented.
Toward coming IPCC AR5, we have performed decadal climate
prediction using three versions of the coupled atmosphere-ocean model
MIROC. In these hindcast experiments, initial conditions were obtained
with an anomaly assimilation procedure using the observed oceanic
temperature and salinity while prescribing natural and anthropogenic
forcing based on the IPCC emission scenarios. Our hindcast experiments
show that initialization contributes to enhance the predictive skills
of AMO and PDO indices for several years in advance. In addition to
these major climate phenomena, the hindcast experiments tend to
simulate a pattern of stepwise sea surface temperature increase in the
Pacific during the late 1990s. Although further studies are need to
enhance predictive skills of decadal climate variability, our results
suggest that the decadal climate prediction has a potential to provide
useful information in order to solve socioeconomic problems arising
from climate change.