| The change of Antarctic ice sheet mass and energy effect on the global sea level change, and the Earth's surface energy balance, such as the global water cycle have an important impact. Dynamic mechanism of the role of Antarctic research, particularly the Antarctic ice sheet numerical simulation of the dynamic process of many uncertainties still exist, so in order to more accurately understand the dynamic process, to accurately predict the direction of development and changes in ice conditions, ice build momentum in a particular region model is very important.This is the first east of the Antarctic ice sheet is the largest ice-flow system- Lambert Glacier-Amery lce Shelf system far key research areas. Carry out research in the basin of the ice sheet dynamics, the establishment of numerical model of flow lines for the "Antarctic ice sheet" that today's long-term impact on human life and to contribute to the development of scientific problems. Main contents and conclusions are as follows:By high-precision DEM, thickness, bedrock elevation data, and the new calculation method of the Amery lce Shelf,1 recalculate the bottom of the freezing and thawing rate; finishing the latest PCMEGA data, and landing near the line of elevation, ice thickness and bedrock Elevation data were constructed. ArcG1S and Matlab software based on two main lines by glaciers, and the light of the above data, the data extraction points. Construction of flow lines based on Matlab model to simulate the ice sheet on the pressure, stress, vertical shear rate, the level of shear rate and draw distance associated with the response curve(1) Create a new calculation method. Amery Ice Shelf at the bottom to re- calculate the melting rate. It was found that the leading edge and the ice shelf ice shelf ice shelf ice west there is the case then freeze, freezing rate of about 2.4mlyr, the whole ice shelf bottom melting rate of maximum maximum 22.1 mlyr. The western end of the ice shelf melting rate of the coastal edge of the area is significantly high. Compared with the previous results, this results in the maximum value of about 15% lower on, to a difference of about three times the minimum. Melting rate of ice shelves within the lower range of the melting rate of}the outflow of large, Amery Ice Shelf is further reflected in a generally stable state.(2) Stress, strain rate changing in the dynamic process of establishing the function and equations to build the ice flow model. The model system consists of four models. Are the ice terrain model; horizontal and vertical flow model; ice temperature change models; and rail lines, time and stress model.(3) The simulation results show that changes in ice cover there is a mutation in the stress zone. Although the ice sheet elevation with increasing distance from the landing lines decrease linearly, but in the line of 200-}OOkrr} from the landing area near the surface slope has undergone an obvious change in the slope of the slope from the previous negative value of the slope after slope is positive. Meanwhile, in the region before the driver strain was positive, driven stress increases with distance; strain w'as positive after the driver, driver stress with distance increases.(4) The edge of glacier flow model shows that basin, near the edge of the glacier basin, the surface temperature distribution is relatively simple, the glacier surface temperature distribution near the basin is relatively complex. Ice temperature distribution within the overall increase with depth show }ed the characteristics of simulation results also show that glacial ice flow near the edge of the basin close to 0. the horizontal velocity, and the horizontal velocity and vertical velocity variations obvious. Glacier Basin, near the edge of the driving stress is zero, indicating that the ice sheet in this region is basically stable state.{5) Building an ideal model of ice flow lines, flow lines have been ice momentum, mass and energy balance of the various evolution curve, that in the fixed boundary conditions, the ice sheet in a stable state of the physical characteristics and our current understanding of the Antarctic ice sheet is consistent. Solving the continuity in the specific model equations, consider the ice temperature at the bottom of simulation boundary- conditions required on the computer simulation the stability of this approach makes the changes in vertical velocity at the edge of the basin with glacier is lar},ely consistent understanding The. Evolution has been quantitatively stable state ice ice flow cross-section elevation, temperature field. stress field change. which is conducive to better analyze the evolution of ice sheet changes in the details of the various physical processes.The simulation work for the Lambert glacier basin, the dynamics of ice flow to provide many basic data, but also for th.e first time numerical simulation of the ice extended to the region. For the LAS system, the dynamics of ice streams to provide reference for further research, but also contribute to the whole dynamic process of East Antarctica.
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