Abstract: Geographic modeling and simulation is an important method for solving environmental issues and providing decision-making. Recently, research related to geographic modeling and simulation in an open web environment is mainly focused on model service sharing, while the calculation speed of model has been less studied. The terrestrial carbon cycle model plays a key role in the simulation of carbon cycle, service-oriented sharing has promoted it's development, but the time-consuming calculation speed limits their widespread applications. The large amount of calculation of terrestrial carbon cycle model results in a large amount of time to obtain the output. Currently, the model sharing strategies have not employed effective ways to improve the calculation performance of terrestrial carbon cycle models. A service-oriented decentralized computing method is proposed to speed up the calculation of these models. The main idea of this method is adding computing nodes to alleviate the pressure of the calculation of the terrestrial carbon cycle model based on the existing model sharing strategies. First, the terrestrial carbon cycle models are published as model services in the open web environment. Then, a task segmentation and dispatch strategy is designed to break the complex computing tasks into small steps and dispatch them to different computing nodes for distributed calculation. The study case of three typical terrestrial carbon cycle models show the feasibility and practicability of the proposed method and it can be used to improve the calculation speed of the terrestrial carbon cycle model.