AN NWP PRECIPITATION PRODUCTS DOWNSCALING METHOD BASED ON DEEP LEARNING
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摘要: 提出一种基于深度学习的数值模式降水产品降尺度方法。利用深度学习的非线性映射能力和对栅格数据的信息提取能力,建立深度超分辨率模型提取不同分辨率数值模式降水产品间相对应的有效信息,从而将低分辨率数值模式降水产品利用提取的信息重构为高分辨率产品,继而通过构建多时次组合降尺度深度模型提取时间关联性进一步提升了重构准确性。基于欧洲中期天气预报中心不同尺度数值模式降水产品的实验表明所提方法能够比常用的双三次插值方法更有效地将低分辨率降水产品转换为对应的高分辨率产品。Abstract: A downscaling method of the Numerical Weather Prediction (NWP) precipitation products based on deep learning is proposed. Based on nonlinear mapping and information extraction of the deep learning network, a deep super-resolution model is established. The model is used to extract the effective corresponding information between low-resolution products and high-resolution products. Then high-resolution products can be reconstructed based on corresponding low-resolution products. Furthermore, we propose a multi-time combination downscaling deep learning model to extract time correlations, and the accuracy is further improved. Several experiments based on different scales of the ECMWF (European Centre for Medium-Range Weather Forecasts) NWP precipitation products are conducted. The results show that the proposed methods can be more effective in refining the resolution of NWP precipitation products than the commonly used method based on bi-cubic interpolation.
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表 1 0.5 °×0.5 °分辨率产品向0.25 °×0.25 °分辨率产品
采用方法 MAE/mm MSE/mm2 多时次组合模型 0.208 0.160 单时次模型 0.216 0.175 双三次插值 0.388 0.498 表 2 1 °×1 °分辨率产品向0.25 °×0.25 °分辨率产品转换
采用方法 MAE/mm MSE/mm2 多时次组合模型 0.471 0.753 单时次模型 0.494 0.819 双三次插值 0.553 0.985 -
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