Temporal variation of the chlorophyll-a in the Yellow and the East China Sea using the coupled POLCOMS-ERSEM model

Abstract

Seasonal and interannual change of the chlorophyll-a(Chl-a) were analyzed based on the three dimensional coupled marine ecosystem model from 1992 to 2001 in the Yellow and the East China Sea(YECS) characterized by high productive ecosystem. We have applied the POLCOMS (Proudman Oceanographic Laboratory Coastal Ocean Modelling System) ocean circulation model and the ERSEM (European Regional Seas Ecosystem Model) biogeochemical model with a horizontal resolution of 0.1° and 40 layers in the vertical. The monthly SeaWiFS chlorophyll-a over the period of 1998 to 2001 have been used for a validation. In general, the model shows the similar seasonal trend with the satellite data.We selected the specific areas of 2° × 2° in the central Yellow Sea(YS), the Changjiang River(CR) influencing area and the Kuroshio region(KC) to investigate effectively. In the YS, Chl-a has two peak in spring and autumn and the spring peak time varied from late March in 1998 and early May in 2000 according to the year. The peak maximum biomass increased with rich nutrient supply during this period in the YS at the surface while it varied between the years at the subsurface. Chl-a in KC generally showed about a month earlier spring bloom than in YS and appeared unusual high autumn bloom in 1998 and 2000. The blooming duration in KC was longer than in other regions. In this study, we also try to detect the interaction between biological proce We have applied the POLCOMS (Proudman Oceanographic Laboratory Coastal Ocean Modelling System) ocean circulation model and the ERSEM (European Regional Seas Ecosystem Model) biogeochemical model with a horizontal resolution of 0.1° and 40 layers in the vertical. The monthly SeaWiFS chlorophyll-a over the period of 1998 to 2001 have been used for a validation. In general, the model shows the similar seasonal trend with the satellite data.We selected the specific areas of 2° × 2° in the central Yellow Sea(YS), the Changjiang River(CR) influencing area and the Kuroshio region(KC) to investigate effectively. In the YS, Chl-a has two peak in spring and autumn and the spring peak time varied from late March in 1998 and early May in 2000 according to the year. The peak maximum biomass increased with rich nutrient supply during this period in the YS at the surface while it varied between the years at the subsurface. Chl-a in KC generally showed about a month earlier spring bloom than in YS and appeared unusual high autumn bloom in 1998 and 2000. The blooming duration in KC was longer than in other regions. In this study, we also try to detect the interaction between biological proce