自动微分工具辅助下的伴随模式实现及应用试验

Implementation of Adjoint Model with Automatic Differentiation Tool and Application Experiment

为避免手工方法编写数值模式伴随模式程序的困难并探索利用开源自动微分工具OpenAD/F辅助大气科学领域伴随模式实现方法,本文从正压原始方程模式出发研究了在OpenAD/F辅助下获得其伴随模式的方法,并利用获得的伴随模式分析了登陆台风强度对初值和地形的敏感性。所得结论与采用一种商用自动微分工具得到的伴随模式分析结果一致,这表明此次伴随模式实现工作是成功的,此工作为利用OpenAD/F软件实现更复杂数值模式的伴随模式打下了基础。

To avoid the difficulties of code hand writing of adjoint model of numerical model and explore the methods of implementing adjoint model in atmospheric science with the help of open source automatic differentiation tool OpenAD/F, the OpenAD/F had been used to help getting the adjoint model of the barotropic primitive equation model, which is widely used in theoretical analysis in atmospheric research. The adjoint model was then used to study the sensitivity of simulated landing typhoon strength to initial value and terrain. The study results are consistent with that from another adjoint model implemented with help of a commercial automatic differentiation tool. This shows that the implementation of the adjoint model in the work is successful and the work has laid foundation for later development of more complicated adjoint models with OpenAD/F.