1. Center for Satellite Applications and Research (STAR) Review 09 – 11 March 2010 Satellite Observations of Seasonal Sediment Plume in the Central East China Sea Wei Shi 1 and Menghua Wang 2 (GOVERNMENT PRINCIPAL INVESTIGATOR) 1 Colorado State University/CIRA, 2 NOAA/NESDIS/STAR Seasonal Changes of the Sediment Plume in the Central East China Sea Following Figure shows the seasonal changes of the spatial patterns of the turbid waters in the East China Sea region. The focus of this study is the sediment plume in the central East China. Unlike the permanent existence of the turbidity plume in the coast region, this turbidity plume is highly seasonal. The peak coverage and the highest magnitude of K d (490) occur in the winter (December-February. In the spring (Mar.-May) and autumn (Sep. – Nov.), the plume weakens and shrinks significantly. In all these three seasons, the sediment plume seems to be confined within an area of 50 m isobaths. During the summer, however, the sediment plume in the central East China Sea completely disappears, the diffuse attenuation coefficient K d (490) drops significantly and becomes uniform with the water turbidity in the offshore deep waters Variability of Geophysical Properties in the Sediment Plume Region A station located in the center of the plume at [31.84°N, 124.54°E] (as shown in Fig. 2) is chosen to compute the averaged K d (490), SST and wind speed during each month between 2002 – 2008 in a box of 10 km × 10 km. Seasonal variability of the K d (490) magnitude dominates the turbidity changes within the plume with seasonal K d (490) low of ~ 0.2 m -1 in summer and high ~ 1.5 m -1 min December. The coverage of the turbid waters shows significant seasonal variability with the coverage less than 1 × 10 2 km 2 in the summer and nearly 5 × 10 4 km 2 in the winter. Enhanced mixing due to strong winds and surface cooling during the winter destroy the ocean surface mixed layer and strengthen the re-suspension of the sediment from the bottom. SEASONAL K d (490) CLIMATOLOGY Spring (Mar.-May)‏Summer(Jun.-Aug.)‏ Autumn(Sep.-Nov.)‏Winter(Dec.-Feb)‏ Time series location 0 5 Shanghai Yellow Sea East China Sea Bohai Sea Cheju East China Sea 6-YEAR TIME SERIES AT PLUME CENTER K d (490)‏ Turbid water areaSST and Levitus 0 - 50m TWind speed Mechanism of the Sediment Plume Sea surface height anomaly (SSHA) pattern demonstrates no ocean circulation was responsible for the enhanced sediment plume in the central East China Sea. This seasonal sediment plume in the central East China Sea during the winter is attributed to the strong vertical mixing caused by uniform temperature profile and enhanced winds during the winter. OCEAN COLOR, SST AND SSH OBSERVATIONS ON FEB. 15, 2004 K d (490)(scale: 0 -5) +WIND nLw(645)(scale: 0-8)‏ SST (scale:0-25) SSH anomaly(scale:-30cm-30cm)‏ Sea Surface Temperature (scale: 0 – 25) Requirement: Ecosystems: (1) Advancing understanding of ecosystems to improve resource management, (2) Healthy and productive coastal and marine ecosystems that benefit society. Science: How to quantify seasonal and inter-annual variability of the sediment plume in the central East China Sea, and identify and clarify the physical processes that is responsibility of this seasonal plume? Benefit: Better understand coastal ecosystem, water quality and mechanism of sediment transport in the yellow Sea and East China Sea. Next Step: Study the seasonal and inter-annual observations of MODIS Aqua for the entire China coast regions including the East China Sea, Yellow Sea, Bohai Sea and South China Sea, identify the regional difference of their optical, biological and geochemical features and the corresponding ocean and atmosphere processes associated with these difference.