The earth system simulation

From 1970s, the climate system has been studied as a whole by considering the coupled atmosphere-ocean-cryosphere-land surface physical system. Beginning from early 2000s, coupling between the physical climate system processes and biogeochemical processes has been one of the most important research focuses. This is because that the biogeochemical processes such as the carbon cycle and nitrogen cycle plays very important roles on the climate and environmental changes. Therefore, there have been great efforts to develop numerical models to simulate the above processes in the coupled earth system. There numerical models are the so-called earth system models. The simulations are performed by numerical integrations in the supercomputers. The earth system model is the most complex one in natural science numerical models, reflecting the comprehensive expressions of the earth system knowledge, and is the pacemaker of the earth science advances in different countries and groups. The earth system model is the most important tool for the earth system science development. This paper discusses the scientific background, application demands, the scientific achievements in China, and the future objectives and tasks.