Review and suggestions for estimating particulate organic carbon and dissolved organic carbon inventories in the ocean using remote sensing data

Dissolved organic carbon (DOC) and particulate organic carbon (POC) are basic variables for the ocean carbon cycle. Knowledge of the distribution and inventory of these variables is important for a better estimation and understanding of the global carbon cycle. Owing to its considerable advantages in spatial and temporal coverage, remote sensing data provide estimates of DOC and POC inventories, which are able to give a synthetic view for the distribution and transportation of carbon pools. To estimate organic carbon inventories using remote sensing involves integration of the surface concentration and vertical profile models, and the development of these models is critical to the accuracy of estimates. Hence, the distribution and control factors of DOC and POC in the ocean first are briefly summarized, and then studies of DOC and POC inventories and flux estimations are reviewed, most of which are based on field data and few of which consider the vertical distributions of POC or DOC. There is some research on the estimation of POC inventory by remote sensing, mainly in the open ocean, in which three kinds of vertical profile models have been proposed: the uniform, exponential decay, and Gauss models. However, research on remote-sensing estimation of the DOC inventory remains lacking. A synthetic review of approaches used to estimate the organic carbon inventories is offered and the future development of methods is discussed for such estimates using remote sensing data in coastal waters.