2023年初贵阳机场一次雨雪天气过程诊断分析

Diagnostic Analysis of a Rainy and Snowy Weather Process at Guiyang Airport in Early 2023

文章利用中国地面气象台站2400站的常规观测资料、ERA5分辨率为0.25˚ × 0.25˚的逐小时大气再分析资料、贵阳机场的自动气象观测数据、57816贵阳站的探空数据,对2023年初贵阳机场的一次雨雪天气过程进行了诊断分析。分析表明:2023年1月15~18日贵阳机场出现长达4 d的低温雨雪天气,降水类型涉及雨夹雪、冻雨等,降水相态复杂多变,出现多次转换;700 hPa西南气流和850 hPa及以下东北回流冷空气是贵阳机场本次雨雪过程的主要水汽来源通道;冷空气南下后,中低层冷平流发展强烈,温度迅速降低,700 hPa急流呈现弱–强–弱的变化趋势;冰水、云水含量在整个雨雪天气过程中共存且云中水汽相态分布呈现明显的分层及阶段性变化;上述条件的共同作用造成了2023年1月15~18日贵阳机场雨雪天气以及降水相态的多次转换。

In this paper, using conventional observation data from 2400 Chinese surface meteorological sta-tions, hourly atmospheric reanalysis data with ERA5 resolution of 0.25˚ × 0.25˚, automatic meteor-ological observation data from Guiyang Airport, and sounding data from 57816 Guiyang Station, a diagnostic analysis was conducted on a rainy and snowy weather process at Guiyang Airport in early 2023. The analysis showed that a 4-day long low-temperature rainy and snowy weather occurred at Guiyang Airport from January 15 to 18, 2023, with precipitation types including sleet and freezing rain;the precipitation phase is complex and variable, with multiple transitions occurring;the southwest airflow at 700 hPa and the northeast reflux cold air at 850 hPa and below are the main water vapor sources for the rain and snow process at Guiyang Airport;after the cold air flows southward, the cold advection in the middle and lower layers develops strongly, and the temperature rapidly decreases. The 700 hPa jet shows a weak-strong-weak trend;the content of ice water and cloud water coexists throughout the entire rainy and snowy weather process, and the distribu-tion of water vapor phase in clouds shows obvious stratification and phased changes;the combined effect of the above conditions resulted in multiple transitions in the rainy and snowy weather and precipitation phase at Guiyang Airport from January 15 to 18, 2023.