The 1–31-Day Predictions of the South China Sea Summer Monsoon in the CAMS-CSM Climate Forecast System

The South China Sea summer monsoon (SCSSM) is crucial for the East Asian system, which has been detected from plenty of aspects, while its prediction relatively less investigated on subseasonal timescale. 1–31-day predictions SCSSM, including fundamental dynamic and thermodynamic characteristics, indices, onset date associated circulations, are examined diagnosed different climate systems, i.e., T106 × T255 (with a nudging process added) in Chinese Academy Meteorological Sciences system model (CAMS-CSM). results indicate general decreasing skills with growing lead times. For times 1–10 days, zonal winds at lower (850 hPa) higher (200 levels can be reasonably predicted, as well pseudo-equivalent potential temperatures 850 hPa. Meanwhile, skill level generally shows better performance than that level. capability weak during circulation adjustment period before onset, significant enhancement occurs after that. During analyzed 2011–2020, SCSSM mainly skillful most years, year 2015 result least six pentads earlier observation, subsequently taken failure case further investigation. At level, could not effectively predict weakening eastward withdrawal Western Pacific subtropical high shift wind field onset. As upper rapid northward movement Asia establishment Indochina Peninsula neither captured. In addition, models do show differences cases, but latter tends to more continent.