  This study introduces the second version of the Integrated Climate Model
(ICM). ICM is developed by the Center for Monsoon System Research, Institute of
Atmospheric Physics to improve the short-term climate prediction of the East
Asia-western North Pacific (EA-WNP). The main update of the second version of
ICM (ICM.V2) relative to the first version (ICM.V1) is the improvement of the
horizontal resolution of the atmospheric model from T31 spectral resolution
(3.75{\deg}*3.75{\deg}) to T63 (1.875{\deg}*1.875{\deg}). As a result, some
important factors for the short-term climate prediction of the EA-WNP is
apparently improved from ICM.V1 to ICM.V2, including the climatological SST,
the rainfall and circulation of the East Asian summer monsoon, and the
variability and spatial pattern of ENSO. The impact of El Ni\~no on the EA-WNP
climate simulated in ICM.V2 is also improved with more realistic anticyclonic
anomalies and precipitation pattern over the EA-WNP. The tropical Indian ocean
capacitor effect and the WNP local air-sea interaction feedback, two popular
mechanisms to explain the impact of El Ni\~no on the EA-WNP climate is also
realistically reproduced in ICM.V2, much improved relative to that in ICM.V1.
