Online Hydrological Model Service Based On Web Service

The insufficient communication between model and data resource become a critical problem in the development of modeling. There lacks a general mechanism that can link the model and data resource in research. Researchers are often trapped in the dilemma of ineffective modeling with sufficient data, or effective model with insufficient data. The resources sharing based on Web Service proposes an effective way of using model and data resources to their maximum, and reduces the cost of technical development caused by the communication between model and data, such as the mismatch of input data format, running environment and the requirements of data and parameters.Online hydrological and land surface modeling can provide services such as data analysis, forecasting and decision support for various Internet users. With the development and maturity of the sharing environment of scientific data, the convenient way of utilizing the abundant resources of online data become a new challenge. The researchers hope to work on the related problems with a larger amount of data and models, and those models and data are stored in the distributed way. However, the models and data used in previous studies are generally in the standalone way, which means the model, data and other resources are located on the same computer or server. The local manner of model running tends to limit the access of long distance with different users. The inaccessibility of massive data is sever when the large temporal and spatial scale of hydrological modeling are carried out. Current online modeling services lack standardization of complex model data and parameters, and the close cooperation with scientific data center. This paper tries to set up a close cooperation pattern of online service between model server, data server and client. The Web Service technology is employed to access model and data through interface. The security problems caused by the data limits and direct data access of networked hydrological modeling are avoided. Long-distance access are provided, and the effective sharing and communication between model and data resource are realized.This paper is based on the general workflow with standardized interface to build online hydrological and land surface model and data services. The online service architecture, main interface and key technology, including the transmission of the parameters and data and their format translation, the realization of data query and the return of simulated results by the data servers, are mainly introduced. It makes full use of the computing capability of the model server and the resources of the data center. It can be copied and spread to other similar applications.