On-Line Climate Model Simulation of the Global Carbon Cycle and Verification Using the In Situ Observation Data

Using a global climate model that includes a new land surface ecosystem model, a numerical simulation under conditions of the actual vegetation was performed. The values of atmospheric carbon dioxide concentration calculated by the model were verified using the in situ observation data. Concerning the seasonal cycle patterns in the Northern Hemisphere, the model could successfully reproduce the features of the seasonal cycle patterns of the observed data. Also in the equatorial zone and in the low latitudinal zone in the Southern Hemisphere, the model could generally reproduce the features of the seasonal cycles of the observed data. In the middle and the high latitudinal zones in the Southern Hemisphere, the amplitudes of the seasonal cycles calculated by the model were somewhat larger than those of the observed data. The model could, however, reproduce the typical seasonal cycles in the Southern Hemisphere, which are opposite to those in the Northern Hemisphere. The value of increase trend of the global mean surface carbon dioxide concentration simulated by the model was somewhat larger than that of the observed data. The increase trend should decrease when the effects of the temperature increase and the ocean uptake increase were considered. For the values of carbon cycle elements of all vegetation types mean, although the value of vegetation carbon storage was almost the same as the results of other models, the values of soil carbon storage and net primary production were relatively larger than those of other estimations.