Design And Implementation For Online Permafrost Model Service

The application of permafrost model to simulate the spatial distribution and features of hydrothermal of permafrost has significant meaning in environmental protection,utilization of water resources and maintenance of infrastructure.However,there are limitations in the application of permafrost model under the conventional independent and isolate network environment,which include: users are required to possess professional knowledge in programming,compiler and configurator when utilizing the model since most of the permafrost models are in the form of mathematical formula,source code or executable program;there must be high coupling between the model and data since complicated pretreatment processes are needed before executing the model simulation to convert the acquired multi-source heterogeneous data into the input form required by the model.Solutions to model service are proposed targeting the existing issues in the application of permafrost model;the research on the design and realization of the permafrost model service is conducted as well.The following tasks were completed with priority: First,the design,based on the different components,has realized the online service interface of permafrost model as the interface provided by the model components would read and pretreat the metadata and execute the model program,while the interface provided by data components would acquire and upload the input data.In addition,the interface provided by functional components would verify the model results and conduct visualization.Second,the input data of the permafrost model is divided into drive data and model specifications targeting the problems of too-large numbers of input data and complicated pretreatment of data in the semiphysical and physical model of permafrost and based on the data divided to propose the data delivery method which is suitable for most permafrost models.With the overall designing,GIS tools,open source software framework and model program are combined to realize the functions of the interfaces for each component.Finally,the empirical statistical model(the elevation model,mean annual ground temperature model)and semi-physical model(the surface frost number model,the temperature at the top of permafrost)were applied to simulate the spatial distribution of permafrost at Qinghai Tibet Plateau and the physical model GIPL2.0 was applied to simulate the hydrothermal status of the permafrost active layer at Tanggula Station.The results indicate that the online permafrost model service can offer new methods and means to the simulation of permafrost which enables easier discovery and acquisition of permafrost model.In addition,the new methods and means will lower the difficult of applying the model and allow more users to be able to use it.The model encapsulation and management through proxy model can prevent the change to the model program and will lower the development cycle and cost of the permafrost model service which allows the addition of more permafrost models.Through data base the permafrost model service coupled the method of configured profile template to realize the automatic acquisition and transformation of model input data,which prevent the low efficiency in spatial data delivery and the issues in complicated pretreatment of data during the application of permafrost model.The treatment function after the simulation provided by online permafrost model service allows users to verify and visualize the measured data and simulation results,which enables the analysis of reasons of errors in simulation via the direct assessment of the simulation results and the observation of the consistency in the spatial distribution trend of the results.