基于再分析资料ERA5计算对流层延迟精度分析

Accuracy Analysis of Tropospheric Delay Calculation Based on Reanalysis Data ERA5

摘要: 对流层延迟是GNSS导航定位的重要误差源，目前有多种方法可实现天顶对流层延迟(ZTD)的估算。ERA5作为ECMWF发布的最新一代再分析产品，能够提供覆盖全球的高时空分辨率气象资料，据此可估算出高精度的ZTD。然而，当前对ERA5对流层延迟产品精度评价的相关研究仍甚少。本文以高精度的IGS对流层延迟产品为参考，在编程实现ERA5对流层延迟估算的基础上，对其精度进行了评价。试验结果表明：相较于GPT2w-1S模型和GPT3-1S模型，由ERA5气象资料估算的ZTD产品具有更高的精度，均方根误差分别提高了27.53 mm和27.50 mm。

Abstract: Tropospheric delay is an important error source for GNSS navigation and positioning, and there are many methods to estimate the zenith tropospheric delay (ZTD). As the latest generation of reanalysis products released by ECMWF, ERA5 can provide meteorological data with high spatial and temporal resolution covering the whole world, based on which high-precision ZTD can be estimated. However, there are still few related studies on the accuracy evaluation of ERA5 tropospheric delay products. This paper takes the high-precision IGS tropospheric delay product as a reference, and evaluates its accuracy on the basis of programming the ERA5 tropospheric delay estimation. The experimental results show that compared with the GPT2w-1S model and the GPT3-1S model, the ZTD product estimated from the ERA5 meteorological data has higher accuracy, and the root-mean-square deviation is increased by 27.53 mm and 27.50 mm, respectively.