AI 中文总结
本研究利用2006-2024年VEX和Akatsuki的RO数据对比Venus-GRAM/VCD，发现金星中高层大气温度存在系统偏差与年代际变化，调整云辐射强迫可部分协调偏差，但需更新气候学与模型参数化方案。
AI 中文摘要
我们利用2006-2024年金星快车（Venus Express）和晓号（Akatsuki）的无线电掩星（RO）测量数据，研究金星45-80 km中高层大气的热结构。将反演得到的温度廓线与Venus-GRAM及金星气候数据库（Venus Climate Database, VCD）的气候预测结果进行对比。观测到RO温度与模型气候数据之间存在超过10 K的系统偏差，尤其在南北半球的高纬度地区。该长期数据集进一步揭示，低纬度至中纬度区域的温度可能存在年代际时间尺度的变化，且这种变化在高海拔地区的一致性减弱。对温度异常值进行的后分层和自助法分析表明，采用的分析方法量化的纬度采样偏差无法解释低纬度至中纬度及极地纬度观测到的时间变化，而中纬度至高纬度的趋势则受RO探测稀疏且分布不均的影响。对VCD模拟采用修改后的云反照率输入进行敏感性测试，结果显示调整云辐射强迫可部分协调偏差，尤其在60 km以下的低海拔地区；但在云顶以上的低纬度区域，与观测的偏差显著增大，因此无法实现VCD与RO的整体协调。这些结果表明，需要整合最新RO测量数据更新经验气候学，并改进金星全球环流模型的物理参数化方案，以更好地捕捉行星中高层大气的全球变化。
英文摘要
We investigate the thermal structure of the Venusian middle atmosphere between 45 and 80 km using radio occultation (RO) measurements from Venus Express and Akatsuki spanning 2006-2024. Retrieved temperature profiles are compared with climatological predictions from the Venus-GRAM and the Venus Climate Database (VCD). Systematic deviations exceeding 10 K are observed between the RO temperatures and model climatologies, particularly at high latitudes in both hemispheres. The long-term dataset further reveals a possible decadal-scale temporal variability in temperatures across the low-to-mid latitude regions. This variability becomes less coherent at higher altitudes. A combination of post-stratification and bootstrap analysis on the temperature anomalies indicates that the observed temporal variability at low-to-mid and polar latitudes is not readily explained by the latitudinal sampling bias quantified using the adopted analysis, while the trends at mid-to-high latitudes are affected by sparse and uneven RO sounding. Sensitivity tests using modified cloud albedo inputs in VCD simulations show that adjusting cloud radiative forcing partially reconciles the discrepancies, especially at the lower altitudes, below 60 km. However, above the cloud top, at the lower latitudes, the divergence from the observations increases significantly, thereby failing to provide a general reconciliation between VCD and RO. These results highlight the need for updated empirical climatologies incorporating recent RO measurements and for improved physical parameterizations in Venus general circulation models to better capture the global variability in the planet's middle atmosphere.
Comments22 pages, 13 figures, 1 table, Accepted for publication in Icarus
DOI：10.1016/j.icarus.2026.117307
