The geographical location of Central India (CI) is often under the influence of a variety of weather phenomena, viz., the Indian Summer Monsoon (ISM) and its associated low-pressure systems, heat waves, cold waves, and western disturbances. The present study investigates the Vertical Structure of atmospheric Turbulence (VST) in terms of the refractive index structure parameter ($C_n^2$), in the troposphere and lower stratosphere over the core monsoon zone in the CI. Ten years (2011−2020) of GPS-radiosonde (GPS-RS) measurements and reanalysis datasets are employed to bring out the turbulence characteristics over the study region. The strong turbulence values below 12 km during the monsoon season are due to the frequent convective instabilities and higher vertical velocities, whereas contrasting VST is noted during non-monsoon seasons with significant turbulence intensities reaching up to the upper levels. The frequent convective instabilities and updrafts make the monsoon season's VST more homogeneous isotropic turbulence in character. Observed seasonal variability in VST is attributed mainly to moisture availability, thermal structure, presence of tri-model clouds, and a flip-flop pattern of mid-tropospheric wind circulation conditions. The early signature of the ISM onset with the higher cold cloud fraction is responsible for the observed weak turbulence zone centered at 14 km altitude. This striking weak $C_n^2$ < 10⁻¹⁷ m^−2/3 over the monsoon core zone VST is one of the most intriguing features observed in the present study. The signatures of various weather conditions such as heat waves, depressions, and cold waves are reflected in the observed variations of the VST during summer, monsoon, and winter, respectively. The variations in the pre/post VST and during specific weather events are attributed to the remarkable difference in relative humidity and temperature conditions. The present results provide a quantitative assessment of VST, including its seasonal evolution over Bhopal, using GPS-RS observations for the first time. The impact of better temporal/height sampling of GPS-RS data is evidenced by implementing the Thorpe method to estimate the outer scale of turbulence. The present analysis will also assist in designing experimental specifications for the proposed wind profiler in CI's Atmospheric Research Testbed for all-weather scale applications.

印度中部 (CI) 的地理位置经常受到各种天气现象的影响，即印度夏季风 (ISM) 及其相关的低压系统、热浪、冷浪和西部干扰。本研究根据折射率结构参数（$C_n^2$)，在 CI 的核心季风区上方的对流层和平流层低层。十年（2011-2020 年）的 GPS 无线电探空仪（GPS-RS）测量和再分析数据集用于显示研究区域的湍流特征。季风季节 12 公里以下的强湍流值是由于频繁的对流不稳定性和较高的垂直速度，而在非季风季节注意到对比的 VST，显着的湍流强度达到上层。频繁的对流不稳定性和上升气流使季风季节的VST更具有均匀的各向同性湍流特征。观测到的 VST 季节性变化主要归因于水分可用性、热结构、三模式云的存在、以及对流层中部风环流条件的翻转模式。具有较高冷云分数的 ISM 开始的早期特征是观测到的以 14 公里高度为中心的弱湍流区的原因。这个惊人的弱$C_n^2$< 10 ^-17  m ^-2/3季风核心区 VST 上空是本研究中观察到的最有趣的特征之一。热浪、低气压和冷浪等各种天气条件的特征分别反映在夏季、季风和冬季观测到的 VST 变化中。VST前后和特定天气事件期间的变化归因于相对湿度和温度条件的显着差异。目前的结果首次使用 GPS-RS 观测对 VST 进行了定量评估，包括其在博帕尔上空的季节性演变。通过实施索普方法来估计湍流的外部尺度，证明了对 GPS-RS 数据进行更好的时间/高度采样的影响。