My major research efforts have been directed at understanding the structure and functioning of plankton ecosystems and their response to physical forcing so that a capability can be developed to forecast responses of marine ecosystems to global change (Goes et al, 2001. 2004, 2005; Limsakul et al., 2001). For my research work I rely on an approach that examines phytoplankton at the cellular level, where changes in phytoplankton cell physiology, biochemistry and optical properties are studied as a means of evaluating their role and response to changes in the environment (Goes et al., 2002). With the help of empirical or semi-analytical modeling techniques, information obtained at the cellular level is then extrapolated to regional and global scales using data from satellites and ships. Research on this front has led to the development of satellite based methods that have made it possible to assess how large-scale climatic events such as El-Niño and La Niña, the North Atlantic Oscillation impact atmospheric CO2 draw down by phytoplankton (export production). (Goes et al, 200, 2004) Ship and satellite studies, currently underway in the Arabian Sea, have provided the first indications of rapid ecosystem changes being brought about by global warming and the rapid decline in snow over the Himalayan-Tibetan Plateau region (Goes et al.,2005, Gomes et al., 2008; 2009). Bio-optical and phytoplankton physiological studies being undertaken in the Bering Sea are aiding in the development of regional satellite ocean color algorithms that will help assess how the Bering Sea shelf ecosystem is responding to changes in sea-ice concentrations. In the Amazon River Plume, ship and satellite are being collected to help understand the influence of the Amazon River on the pelagic ecosystem, carbon cycling and sequestration in the tropical north Atlantic and the sensitivity of this ecosystem to anthropogenic climate change.