Abstract. Current climate models have difficulty representing realistic wave-mean flow interactions, partly because the contribution from waves with fine-vertical scales is poorly known. There are few direct observations of these waves and most models have difficulty resolving them. This observational challenge cannot be addressed by satellite or sparse ground-based methods. The Strateole-2 long-duration stratospheric superpressure balloons that drift with the horizontal wind on constant density surfaces provide a unique platform for wave observations across a broad range of spatial and temporal scales. For the first time, balloon-borne Global Navigation Satellite System (GNSS) radio occultation (RO) is used to provide high vertical resolution equatorial wave observations. By tracking navigation signal refractive delays from GPS satellites near the horizon, 40–50 temperature profiles were retrieved daily, from balloon flight altitude (∼20 km) down to 6–8 km altitude, forming an orthogonal pattern of observations over a broad area (±400–500 km) surrounding the flight track. The refractivity profiles show an excellent agreement of better than 0.2 % with co-located radiosonde, spaceborne COSMIC-2 RO and reanalysis products. The 200–500 m vertical resolution and consecutive sampling in time and space make it possible to extract properties of Kelvin waves to shorter period gravity waves with vertical wavelengths as short as 2–3 km. A short dataset from the extra Galileo and GLONASS constellations demonstrates the feasibility to nearly double the sampling density in planned follow-on campaigns. The results will contribute to improved estimates of momentum forces for wave driving of the Quasi-biennial Oscillation (QBO) and improved QBO representation in models, and illustrate the importance of measuring intrinsic period in the Lagrangian reference frame.

中文翻译：

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在 Strateole-2 战役中通过球载全球导航卫星系统无线电掩星解析的赤道波

摘要。当前的气候模型难以代表真实的波浪-平均流相互作用，部分原因是对具有精细垂直尺度的波浪的贡献知之甚少。对这些波的直接观察很少，大多数模型都难以解决它们。这一观测挑战无法通过卫星或稀疏的地面方法解决。Strateole-2 长期平流层超压气球在恒定密度表面上随水平风漂移，为在广泛的空间和时间尺度上进行波浪观测提供了一个独特的平台。球载全球导航卫星系统 (GNSS) 无线电掩星 (RO) 首次用于提供高垂直分辨率赤道波观测。通过跟踪地平线附近 GPS 卫星的导航信号折射延迟，每天检索 40-50 个温度剖面，从气球飞行高度（~20 公里）到 6-8 公里高度，在飞行轨迹周围的广阔区域（±400-500 公里）上形成正交观测模式。折射率分布与共址无线电探空仪、星载 COSMIC-2 RO 和再分析产品的一致性优于 0.2%。200~500 m的垂直分辨率和时空连续采样使得将开尔文波的特性提取为垂直波长短至2~3 km的较短周期重力波成为可能。来自额外伽利略和 GLONASS 星座的简短数据集证明了在计划的后续活动中将采样密度几乎翻倍的可行性。