Ten-year worth of absolute gravity (AG) campaigns at Onsala Space Observatory (OSO), Sweden, are simultaneously reduced using synchronous data from a superconducting gravimeter (SG). In this multi-campaign adjustment, the a priori models commonly applied for each setup in AG-alone experiments are sidestepped in favour of SG records and a model to estimate its drift. We obtain a residual (hourly samples) at the 5 nm/s2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^2$$\end{document} RMS level, reducing the SG data with a range of ancillary data for the site’s exposure to ocean and atmospheric loading, and hydrology effects. The target quantity in AG projects in the Baltic Shield area is the secular change of gravity dominated by glacial isostatic adjustment with land uplift as its major part. Investigating into the details of the associated processes using AG requires a long-term stable reference, which is the aim of international comparison campaigns of FG5 instruments. Two of these have been campaigning at OSO since 2009 when the SG had been installed. In the simultaneous inversion of all sixteen campaigns, we identify weaknesses of AG observations, like varying systematic offsets over time, excess microseismic sensitivity, trends in the AG data and side effects on the SG’s scale factor when campaigns are evaluated one by one. The simultaneous adjustment afforded us an SG scale factor very near the result from a campaign with a prototype quantum gravimeter. Whence, we propose that single-campaign results may be biased and conjectures into their variation, let alone its causes misleading. The OSO site appears to present manageable problems as far as environmental influences are concerned. Our findings advocate the use of AG instruments and procedures that are more long-term stable (reference realization), more short-term stable too (setup drifts), less service craving and more resilient to microseismic noise.

中文翻译：

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超导重力仪和地震仪揭示 FG5 的偏移、趋势和噪声：昂萨拉太空天文台的观测可以告诉我们什么

使用来自超导重力仪 (SG) 的同步数据同时减少了瑞典昂萨拉太空天文台 (OSO) 为期十年的绝对重力 (AG) 活动。在这种多运动调整中，在单独的 AG 实验中通常应用于每个设置的先验模型被回避，有利于 SG 记录和估计其漂移的模型。我们在 5 nm/s2\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{ 处获得残差（每小时样本） mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$^2$$\end{document} RMS 级别，使用一系列用于网站曝光的辅助数据来减少 SG 数据海洋和大气载荷以及水文效应。波罗的海地盾区AG项目的目标量是以陆地抬升为主要部分的冰川均衡调整为主的重力长期变化。使用 AG 调查相关过程的细节需要长期稳定的参考，这是 FG5 仪器国际比较活动的目标。其中两个自 2009 年安装 SG 以来一直在 OSO 竞选。在所有 16 个活动的同时反演中，我们确定了 AG 观测的弱点，例如随时间变化的系统偏移、过度的微地震敏感性、AG 数据的趋势以及在逐一评估活动时对 SG 比例因子的副作用。同时调整为我们提供了非常接近原型量子重力计运动结果的 SG 比例因子。何处，我们建议单个广告系列的结果可能存在偏差并推测其变化，更不用说其原因误导了。就环境影响而言，OSO 站点似乎存在可管理的问题。我们的研究结果提倡使用更长期稳定（参考实现）、短期更稳定（设置漂移）、更少的服务渴望和更能抵御微震噪声的 AG 仪器和程序。