IWV data from ground-based GNSS receivers during MAESTRO campaign

<p>Integrated Water Vapour (IWV) estimates were computed for 42 ground-based GNSS receivers located in two domains, on the East side and West side of the tropical Atlantic. Eight receivers are available in eastern domain, among which CPVG and SAL2 in the premises of INMG in Espargos, Sal island, and PRAA on the roof of a building of the University of Cape Verde in Praia. Thirty-four receivers are available in the western domain, extending from Guadeloupe to French Guyana, among which are the two receivers operating since the end of 2019 at the BCO where they were installed for the previous campaign EUREC4A (Bock et al., ESSD, 2021).

This data set is a post-processing of the raw GNSS measurements with GipsyX software using the final GNSS satellite products from JPL. Data are processed in the Precise Point Positioning (PPP) mode and ZTD parameters are estimated every 5 min. The ZTD date are afterwards screened for outliers and converted to IWV using ERA5 surface pressure and weighted mean temperature interpolated from the 1-hourly pressure-level data (see Bock et al., ESSD, 2021, for details). The final IWV data are provided with a 1-hourly sampling for the period from 1 August to 30 September 2024. </p>

大气可降水量（Integrated Water Vapour, IWV）的估算值针对分布于两个区域的42台地基全球导航卫星系统（Global Navigation Satellite System, GNSS）接收机计算得到，两个区域分别位于热带大西洋的东侧与西侧。东侧区域部署有8台接收机，其中CPVG与SAL2位于萨尔岛埃斯帕戈斯的INMG场地内，PRAA则设于佛得角大学普拉亚分校某建筑的楼顶。西侧区域部署有34台接收机，覆盖范围从瓜德罗普延伸至法属圭亚那，其中包含两台自2019年底起在BCO运行的接收机，该两台设备为此前EUREC4A科考任务所部署（Bock et al., ESSD, 2021）。

本数据集为原始GNSS观测数据的后处理成果，采用GipsyX软件，结合喷气推进实验室（Jet Propulsion Laboratory, JPL）发布的最终版GNSS卫星轨道产品完成解算。解算过程采用精密单点定位（Precise Point Positioning, PPP）模式，每5分钟估计一次天顶对流层延迟（Zenith Tropospheric Delay, ZTD）参数。随后对ZTD数据开展异常值筛查，并结合ERA5地表气压以及从1小时分辨率气压层数据插值得到的加权平均温度，将其转换为IWV，详细方法参见Bock等，《地球系统科学数据》（ESSD）, 2021。最终IWV数据的时间采样分辨率为1小时，覆盖时段为2024年8月1日至2024年9月30日。