Abstract:

Arctic ecosystems and global climate are closely related. This paper studies the distributions and the coupling relationship between Chlorophyll a (Chl a) and aerosol optical thickness (AOD) in Greenland Sea (10°W—10°E, 70°N—85°N) during 2003—2009 using satellite ocean colour data from MODIS Aqua. The regression analysis of EViews shows that Chl a and AOD are correlated with a time lag. Based on the lag of Chl a and AOD, co-integration inquiry finds that there is co-integration between them, which means that they will have a long-term equilibrium relationship. In general, Chl a starts from March, and gradually increases to a peak in July. The peak of AOD is usually in May, 11 weeks before Chl a. After shifting the time lag, the correlation between Chl a and AOD is 0.98 in the spring in 80°N—85°N. Apart from the year of 2005, when Chl a and AOD had no time lag, the other years’ intervals increased about 6 weeks within the 7 years. The peaks of AOD shifted one and half months ahead, while Chl a also shifted about two months ahead. In northern part (75°N—85°N), Chl a and AOD were much higher in the summer and autumn of 2009 than those in other years. The reason could be the much larger ice melting and higher AOD. The results indicate that the global warming has significant impact on the ecosystem in the Arctic Ocean.

Key words: Chlorophyll a (Chl a), aerosol optical thickness (AOD), ecosystem, regression analysis, co-integration.