# A Novel GPU-Based Acceleration Algorithm for a Longwave Radiative Transfer Model
## 5 Algorithm Implementation
### trrnmc_d
Furthermore, the current acceleration algorithm of the RRTMG_LW displayed better calculation performance than its 2D algorithm did. The future work will include three aspects. First, the proposed algorithm will be further optimized. For example, read-only arrays in CUDA code will be considered for inclusion in the CUDA texture memory, rather than in the global memory. Second, the I/O transfer in the current G-RRTMG_LW still costs a great deal of time, so the methods of reducing the I/O transfer between the CPU and GPU will be studied. Third, the G-RRTMG_LW currently only runs on one GPU. The CAS-ESM often runs on several CPUs and nodes, so the acceleration algorithm on multiple GPUs will be studied. An MPI+CUDA hybrid paradigm will be adopted to run the G-RRTMG_LW on multiple GPUs. Conceptualization, [PERSON]; Methodology, [PERSON], [PERSON] and J.J.; Supervision, [PERSON]; Validation, [PERSON] and Y.Z. ; Writing--original draft, [PERSON]; Writing--review & editing, [PERSON] and H.Z. All authors have read and agreed to the published version of the manuscript. This work was supported in part by the National Key Research and Development Program of China under Grant 2016 YFB0200800, in part by the National Natural Science Foundation of China under Grant 61602477, in part by the China Postdoctoral Science Foundation under Grant 2016M601158, in part by the Fundamental Research Funds for the Central Universities under Grant 2652017113, and in part by the Open Research Project of the Hubei Key Laboratory of Intelligent Geo-Information Processing under Grant KLIGIP-2017A04. The authors would like to acknowledge the contributions of [PERSON] for insightful suggestions on algorithm design. The authors declare no conflict of interest.The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results. ## References

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