This paper is an introduction to a new project of the National Basic Research Program of China, “Studies of upper ocean structure, variability and predictability based on Argo observation network”. We first discuss the great opportunities and challenges for ocean and atmosphere sciences provided by the international Argo program. Then, we briefly review the scientific advances in the studies of northwest Pacific and tropic Indian-Pacific Oceans, the focus area of our proposed research. At last we outline the key scientific questions to address and the main research components of the present project.