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A massive bloom of green macroalgaeUlva proliferaoccurred in June 2008 in the Yellow Sea, resulting in perhaps the largest “green tide” event in the history of bloom research. The covered area is about 1,200 km2and the impacted area reached 40,000 km2on 31 May. This also occurred in the following two years, 2009 and 2010. We analyzed the satellite data from MODIS and the results showed that sea surface temperature increased 1–3°C inU. proliferabloom locations. The macroalgae in the water may have been the cause of the increase of sea surface temperatures. Rapid increases ofU. proliferabiomass during the blooms may have increased radiation absorption of the water, and thus enhanced the rate of heating at the sea surface. The present study represents a preliminary observation, which is an important step for understanding influences of macroalgae on ocean surface conditions. [ABSTRACT FROM AUTHOR]

The diurnal sea surface temperature (D-SST, which is the daytime SST minus the night-time SST) and its relationship with heavy phytoplankton blooms were observed using satellite and in situ data. Two phytoplankton bloom events covering large areas in the East China Sea (ECS) were analysed to investigate the reactions among D-SST, chlorophyll-a (chl-a) concentration, suspended sediment (SS), coloured dissolved organic matter (CDOM), wind speed (WS) and solar radiation (SR). The results showed a positive relationship between D-SST and chl-a concentration in phytoplankton bloom areas. Further analyses of 12 major phytoplankton bloom events (total area >1000 km2) occurring between 2000 and 2005 in the ECS, accompanied by in situ observation data in Daya Bay, confirmed a positive correlation between chl-a concentration and D-SST. These results showed that an increase in D-SST may be found in heavy phytoplankton bloom areas. The present study represents an important step for understanding the influence of phytoplankton on ocean conditions. [ABSTRACT FROM AUTHOR]

Harmful algal blooms (HABs) occur frequently in the South China Sea (SCS), causing enormous economic losses in aquaculture. We analyzed historical HAB records during the period from 1980 to 2003 in SCS. We found that HABs-affected areas have expanded and the frequency of HABs varied during this period. The seasonal and annual variations, as well as causative algal species of HABs are different among the four regions. Areas with frequent HABs include the Pearl River Estuary (China), the Manila Bay (the Philippines), the Masinloc Bay (the Philippines), and the western coast of Sabah (Malaysia). HABs occurred frequently during March–May in the northern region of SCS, May–July in the eastern region, July in the western region, and year-round in the southern region. Among the species that cause HABs, Noctiluca scintillans dominated in the northern region, and Pyrodinium bahamense in the southern and eastern regions. Causative species also varied in different years for the entire SCS. Both P. bahamense and N. scintillans were the dominant species during 1980–2003. Some species not previously recorded formed blooms during 1991–2003, including Phaeocystis globosa, Scrippsiella trochoidea, Heterosigma akashiwo, and Mesodinium rubrum. Variations in HABs are related to various regional conditions, such as a reversed monsoon wind in the entire SCS, river discharges in the northern area, upwelling in Vietnam coastal waters during southwest winds and near Malaysia coastal waters during northeast winds, and eutrophication from coastal aquaculture in the Pearl River estuary, Manila Bay, and Masinloc Bay. [ABSTRACT FROM AUTHOR]

Abstract: Monitoring of spatial and temporal distribution of chlorophyll (Chl-a) concentrations in the aquatic milieu is always challenging and often interesting. However, the recent advancements in satellite digital data play a significant role in providing outstanding results for the marine environmental investigations. The present paper is aimed to review ‘remote sensing research in Chinese seas’ within the period of 24 years from 1978 to 2002. Owing to generalized distributional pattern, the Chl-a concentrations are recognized high towards northern Chinese seas than the southern. Moreover, the coastal waters, estuaries, and upwelling zones always exhibit relatively high Chl-a concentrations compared with offshore waters. On the basis of marine Chl-a estimates obtained from satellite and other field measured environmental parameters, we have further discussed on the applications of satellite remote sensing in the fields of harmful algal blooms (HABs), primary production and physical oceanographic currents of the regional seas. Concerned with studies of HABs, satellite remote sensing proved more advantageous than any other conventional methods for large-scale applications. Probably, it may be the only source of authentic information responsible for the evaluation of new research methodologies to detect HABs. At present, studies using remote sensing methods are mostly confined to observe algal bloom occurrences, hence, it is essential to coordinate the mechanism of marine ecological and oceanographic dynamic processes of HABs using satellite remote sensing data with in situ measurements of marine environmental parameters. The satellite remote sensing on marine environment and HABs is believed to have a great improvement with popular application of technology. [Copyright &y& Elsevier]