青藏高原地区地基微波辐射计的适用性评估研究

Suitability Evaluation of a Ground-Based Microwave Radiometer over the Qinghai-Xizang Plateau

摘要: 为评估地基微波辐射计在青藏高原地区的适用性，本文利用2025年10~12月青海西宁站的辐射计连续观测数据与同期探空资料进行对比，分析了温度、相对湿度和水汽密度垂直廓线的反演精度及误差特征，并选取典型雨、雪天气过程进行应用检验。结果表明：TK001辐射计在高原秋、冬季整体性能可靠，温度反演精度最优(R = 0.91)，水汽密度次之(R = 0.89)，均能清晰反映高原近地层逆温结构；相对湿度精度偏低(RMSE = 13.43%)，呈系统性干偏差。三类廓线误差均呈现“近地层最大、随高度递减”的特征，与高原边界层逆温频发及低层水汽浓度极低密切相关。降雨过程中，辐射计能有效捕捉水汽的快速积聚与消散；降雪条件下，受天线罩积雪及固态粒子散射干扰，数据可靠性下降。研究证实该设备具备在高原业务化应用的潜力，可为数值预报同化和边界层监测提供有力支撑，但需针对高原特殊大气背景开展算法本地化改进。

Abstract: To evaluate the suitability of the domestic TK001 ground-based microwave radiometer over the Qinghai-Xizang Plateau, continuous radiometer observations from October to December 2025 at Xining station in Qinghai Province were compared with concurrent radiosonde data. The retrieval accuracy and error characteristics of vertical profiles of temperature, relative humidity, and water vapor density were analyzed, and typical rain and snow weather events were examined for application validation. Results indicate that the TK001 radiometer performs reliably overall during the plateau autumn and winter seasons. The temperature retrieval exhibits the highest accuracy (R = 0.91), followed by water vapor density (R = 0.89), both of which clearly capture the near-surface inversion structure characteristic of the plateau. The relative humidity retrieval shows a lower accuracy (RMSE = 13.43%) with a systematic dry bias. The errors in all three profile types exhibit a common feature of being largest near the surface and decreasing with height, which is closely related to the frequent occurrence of boundary-layer inversions and the extremely low water vapor concentration in the lower layers over the plateau. During rainfall events, the radiometer effectively captures the rapid accumulation and dissipation of water vapor; however, under snowfall conditions, data reliability decreases due to snow accumulation on the radome and scattering interference from solid hydrometeors. This study confirms that the TK001 radiometer has the potential for operational application over the Qinghai-Xizang Plateau and can provide valuable profiling data for numerical weather prediction assimilation and boundary-layer monitoring. However, further development of locally adapted retrieval algorithms tailored to the unique atmospheric conditions of the plateau is necessary.