Climate response and spatial-temporal model on the inter-annual change of winter temperature-salinity in the East China Sea

Spatial distributions and time variation characteristics were analyzed using Rotated Empirical Orthogonal Function (REOF) and spectrum analysis methods using surface and bottom temperature and salinity data in February of 1976-2013 along 30 degrees N section in the East China Sea. Result showed that temperature trends can be divided into western part and east part, salinity trend divided into western, middle and eastern part. The first mode of surface temperature presented a quasi-equilibrium trend and the range was higher in the near-shore than the offshores, first mode of bottom temperature presented a decreasing trend; surface salinity had a decreasing trend and the extent was higher in the near-shore than the offshores, the bottom salinity showed a decreasing trend in recent years. The temperature inter-annual variability related to El Nino closely; short-term shocks of salinity related to El Nino, and long-term changes had something to do with PDO.