Quantitative analysis of sea level rise caused by continental input

Abstract

Researchers agree that there are two main causes to sea-level rise: melting of land-ice and thermal expansion of ocean water due to global climate warming. However there exist several secondary causes that can result in sea level rise, which used to be ignored. In this study we firstly qualitatively analyzed several secondary reasons that can also cause sea level rise such as land reclamation projects, coastal erosion, river sediment, and so on. Then a mathematical model was built, by the model we quantitatively estimated the sea level rise rates that caused by river sediment and all terrestrial materials discharged into the sea. The concept of “absolute sea level rise” and “relative sea level rise” were put forward in this process, “absolute sea level rise” means the sea level rise compared with level surface, “relative sea level rise” means the sea level rise compared with the land surface. The “relative sea level rise” rate usually greater than “absolute sea level rise” rate because of the terrestrials discharged into the sea not only result in sea level rise but also cause land surface decrease. Our calculation result shows that terrestrial material input could cause an absolute sea level rise by about 0.03484mm per year, and a relative sea level rise by 0.1327 mm per year. All the terrestrial materials into the sea could cause absolute sea-level rise by 0.04099mm per year, and relative rise by about 0.1561mm. Although the relative sea-level rise rate of terrestrial material input is about only one-tenth of the current sea-level rise rate, this is a one-way and persistent process. From a long-term point of view, we also should pay attentions to this process.