一个改进的深度学习程序用于气候数据的统计缩小
Ahmed M S Kheir1,2, Abdelrazek Elnashar3, Alaa Mosad1,2
1International Center for Agricultural Research in the Dry Areas (ICARDA), Maadi 11728, Egypt.
Heliyon
|August 4, 2023
概括
深度学习成功地缩小了埃及的气候变化场景,预计到2100年气温将大幅上升. 这种方法为易受气候影响的干旱地区提供了有价值的数据.
科学领域:
- 气候科学 气候科学
- 人工智能的人工智能
- 环境建模环境建模
背景情况:
- 结合模型相互比较项目第6阶段 (CMIP6) 提供了粗略分辨率的气候变化 (CC) 场景.
- 使用深度学习 (DL) 的统计缩小显示出希望,但需要进一步的研究,特别是对于干旱地区.
- 对于在干旱环境中推断未来的CC场景,DL的适用性仍未得到充分研究.
研究的目的:
- 分析DL适用于降级CMIP6气候变化场景在干旱地区的适用性.
- 使用卷积神经网络 (CNN) 将埃及的最高和最低温度降低.
- 评估DL模型在复制历史和未来气候数据方面的表现.
主要方法:
- 使用一个卷积神经网络 (CNN) 进行统计缩小,称为CNNSD.
- 利用了CanESM5通用循环模型 (GCM) 的CMIP6数据.
- 在两个共享社会经济路径 (SSP) 下的缩减场景:SSP4.5和SSP8.5,对于0.1°分辨率的埃及领域.
主要成果:
- 该CNNSD模型准确地复制了观察到的气候数据,并减少了原始CMIP6场景中的偏差.
- 在SSP4.5下,预计温度将在2100年增加4.8°C (最大) 和4.0°C (最小).
- 在SSP8.5下,预计温度将在2100年增加6.3°C (最大) 和4.2°C (最小).
结论:
- 基于CNN的缩小对于埃及等干旱地区的CMIP6场景是有效的.
- 开发的方法可以支持气候服务,影响研究和脆弱发展中国家的适应战略.
- 建议将多个GCM纳入进一步的研究,以量化不确定性并加强气候变化影响评估.
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