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一个新的埃及电网加权平均温度 (EGWMT) 模型使用GNSS PWV检索中的每小时ERA5再分析数据
Ragab Elhady Sleem1, Mohamed Amin Abdelfatah2, Ashraf El-Kutb Mousa3
1Construction and Utilities Engineering Department, Faculty of Engineering, Zagazig University, Zagazig, Egypt. ragabesd@zu.edu.eg.
Scientific reports
|June 25, 2024
概括
一种名为EGWMT的新模型显著改善了埃及全球导航卫星系统 (GNSS) 气象的加权平均温度 (Tm) 估计. 这种增强的精度有助于精确的沉式水蒸气 (PWV) 检索.
科学领域:
- 地测和地球物理学的地质学.
- 大气科学与气象学
- 卫星导航系统 卫星导航系统
背景情况:
- 对加权平均温度 (Tm) 的精确建模对于全球导航卫星系统 (GNSS) 的气象应用至关重要.
- 在GNSS数据处理中,Tm是将顶点湿延迟 (ZWD) 转换为降水蒸气 (PWV) 的关键参数.
- 现有的Tm模型可能缺乏特定区域应用所需的准确性,需要改进模型.
研究的目的:
- 开发和验证一个改进的Tm模型,命名为EGWMT,专门用于估计埃及各地的Tm.
- 评估EGWMT模型与使用独立数据集的既定Tm模型的性能.
- 为了提高埃及GNSS气象中沉水蒸气 (PWV) 检索的准确性.
主要方法:
- 该EGWMT模型是使用欧洲中期天气预报中心 (ECMWF) 的每小时ERA5再分析数据 (2008-2019) 开发的.
- 模型性能与ERA5再分析数据 (2019-2022) 和放射探测器资料 (2017-2022) 相比进行了评估.
- 与Bevis,Elhaty,ANN和GGTm-Ts模型进行的统计比较使用了平均绝对偏差 (MAB) 和根平均平方误差 (RMSE),以及t测试和F测试.
主要成果:
- 与贝维斯,埃尔哈蒂,ANN和GGTm-Ts模型相比,EGWMT模型表现出更高的性能.
- 与ERA5数据相比,EGWMT的RMSE改进分别为32.5%,30.8%,39%和48.2%.
- 与放射探测器数据相比,EGWMT的RMSE改进分别为22.5%,34%,38%和19.5%,统计学上显著的差异得到证实.
结论:
- 开发的EGWMT模型为埃及的GNSS气象应用提供了更准确的Tm估计.
- 改进的Tm建模直接有助于从GNSS观测中更可靠地检索PWV.
- EGWMT模型对现有模型来说是一个显著的进步,为气象研究提供了更高的准确性和可靠性.
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