评估基于机器学习的缩放框架,以从GPM数据中获得1公里的每日降水量
Tao Sun1, Nana Yan2, Weiwei Zhu2
1College of Geomatics Science and Technology, Nanjing Tech University, Nanjing, 211816, China.
Heliyon
|September 17, 2024
概括
这项研究使用机器学习开发了用于干旱地区的高分辨率降水数据集. 极端梯度提升 (XGBoost) 模型显著提高了准确性,为水文分析提供了有价值的工具.
科学领域:
- 水文和远程传感技术
- 环境科学 环境科学
- 地理空间分析是什么
背景情况:
- 干旱地区的卫星降水数据存在粗略的空间分辨率,限制了详细的水文气象分析.
- 精确的降水监测对于水资源管理和水资源稀缺地区的灾害预防至关重要.
研究的目的:
- 开发和评估机器学习技术,将卫星降雨数据缩小到高时空分辨率.
- 为海河流域创造增强的年度,月度和每日降水产品.
主要方法:
- 评估极端梯度增强 (XGBoost),随机森林 (RF) 和反向传播 (BP) 神经网络用于降水缩小.
- 综合环境变量 (LST,NDVI,DEM,PWV,阿尔贝多) 来缩小全球降雨量测量 (GPM) 数据从0.1°到1公里的分辨率.
- 使用地理差异分析 (GDA) 和Kriging,与陆地雨量数据进行剩余校正和校准.
主要成果:
- 用GDA和Kriging校准的XGBoost模型实现了最高的精度,年降水平均绝对误差 (MAE) 为58.40毫米 (14%的改进).
- 缩小月度和日度降水产品的精度与原始GPM数据相提并论,MAE值分别为11.61mm和1.79mm.
- 影响降水预测的关键变量包括经度,度,DEM,LST_night和PWV.
结论:
- 机器学习,特别是XGBoost,有效地缩小了卫星降水数据,提高了干旱地区的空间和时间分辨率.
- 开发的高分辨率降水产品为水文研究和水资源管理提供了宝贵的参考.
- 准确的降水估计对于了解和管理脆弱环境中的水资源至关重要.
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