Research On Automatic Coupling For Earth System Models Based On Coupling Description Language

Coupling technology is crucial for multi-physical components simulation problem in climate.We analyzed these technologies according to three aspects,driving,connection and architecture style.Then we discussed their deficiencies in ease of use and scalability.The state-of-art coupling technologies may be difficult to increment the components model while also be too complicated for user.Therefore,we studied a scalable and ease of use automatic generation technology for earth system model coupling.As the top-level driving style is convenient for managing the coupled components,we design a top-level driver-based coupler.At the same time,the connection style is designed that components communicate with each other via the coupler.To boost the flexibility and ease-to-use,we proposed a coupler generation framework NOC(not only coupler),which based on XML coupling description.First,we define the coupling problem as a state transfer among components' ' overlapped spatiotemporal space.We then abstract the coupling basic functionalities according this definition: data transfer,data transformation and coordination among coupling processes.Using coupling toolkit in MCT and coupling infrastructure in ESMF,we build a basic coupling library for data transfer,transformation and coupling processes control.Based on top-level driver we construct the coupling driver code.By taking the coupled component as the basis of coupling,we design a programming model in which the driver drive the components' relevant subroutine.Combining the definition of coupling problem and coupling programming model,we proposed an XML-based coupling description language.This coupling description language describes the inner state of a component,the connection among components and coupled model instance configurations.The coupling description language parser in the NOC framework parses the descriptions which represent the components and the relation among components to a set of intermediate representations in accordance with coupling basic library.Coupling instance manager will assemble these intermediate representations and template code and generate a coupling instance.Coupling instance manager also create configuration file according to the specification parsed by parser.To test the ease of use and flexibility of coupling generation framework,we design three experiment to test components stand-alone execution,two coupled components execution and classic coupled model.The experiment confirmed the capacity of our framework in expressing complicated components and their interconnection.