LONG-TERM MONITORING OF THE GREEN-TIDE IN THE EASTERN YELLOW SEA BASED ON THE REMOTE SENSING

Abstract

Floating green-tide in the Yellow Sea occurred every year since 2007. However, most of the researches on the distribution and coverage of rafting macroalgae were conducted in the western Yellow Sea, and there is a lack of research about them in the eastern Yellow Sea. Therefore, aim of this research is to identify the distribution and coverage of green-tide in the eastern Yellow Sea during the last 10 years. To detect the floating green-tide in the eastern Yellow Sea, MODIS, GOCI and Landsat TM/ETM+ imageries were used to analyze the annual changes of green-tide during 2008 to 2017. Massive green-tide was found in the eastern Yellow Sea for the first time in 2008, and the satellite image traced back shows that it originated from the western Yellow Sea. In 2009 and 2011, large mass of green-tide also found in the eastern Yellow Sea, and its largest scale of any green-tide has been found in 2011. Floating green-tide in the eastern Yellow Sea had different route and scales each year, but all macroalgal patches were supplied from the western Yellow Sea. Compared to the western Yellow Sea, coverage of floating green-tide in the eastern part was calculated to be about 5%. In 2011, however, the green-tide scale of the eastern part was accounted for 50% of the western part.m in the eastern Yellow Sea. Therefore, aim of this research is to identify the distribution and coverage of green-tide in the eastern Yellow Sea during the last 10 years. To detect the floating green-tide in the eastern Yellow Sea, MODIS, GOCI and Landsat TM/ETM+ imageries were used to analyze the annual changes of green-tide during 2008 to 2017. Massive green-tide was found in the eastern Yellow Sea for the first time in 2008, and the satellite image traced back shows that it originated from the western Yellow Sea. In 2009 and 2011, large mass of green-tide also found in the eastern Yellow Sea, and its largest scale of any green-tide has been found in 2011. Floating green-tide in the eastern Yellow Sea had different route and scales each year, but all macroalgal patches were supplied from the western Yellow Sea. Compared to the western Yellow Sea, coverage of floating green-tide in the eastern part was calculated to be about 5%. In 2011, however, the green-tide scale of the eastern part was accounted for 50% of the western part.