干旱区研究 ›› 2025, Vol. 42 ›› Issue (10): 1802-1812.doi: 10.13866/j.azr.2025.10.05 cstr: 32277.14.AZR.20251005

• 天气与气候 • 上一篇    下一篇

基于同化探空资料的腾格里沙漠一次强降水过程分析

王雨恬(), 隆霄(), 王号, 陈佑奥, 马星星   

  1. 兰州大学大气科学学院,甘肃 兰州 730000
  • 收稿日期:2025-05-27 修回日期:2025-07-31 出版日期:2025-10-15 发布日期:2025-10-22
  • 通讯作者: 隆霄. E-mail: longxiao@lzu.edu.cn
  • 作者简介:王雨恬(2002-),女,硕士研究生,主要从事中小尺度数值模拟研究. E-mail: wyutian2023@lzu.edu.cn
  • 基金资助:
    国家重点研发计划(2023YFC3206302);国家自然科学基金(42330601)

Analysis of an intense precipitation process in the Tengger Desert based on sounding data assimilation

WANG Yutian(), LONG Xiao(), WANG Hao, CHEN Youao, MA Xingxing   

  1. College of Atmospheric Sciences, Lanzhou University, Lanzhou 730000, Gansu, China
  • Received:2025-05-27 Revised:2025-07-31 Published:2025-10-15 Online:2025-10-22

摘要:

降水是干旱半干旱地区土壤水分的主要来源,降水的准确预测对该地区水资源的有效利用和减灾防灾有指导意义。干旱与半干旱地区观测数据稀疏,且再分析资料在沙漠地区存在较大误差,共同导致了数值模式对该地区降水模拟能力的不足。为此,本文选取一次发生在腾格里沙漠的降水过程,通过同化探空资料来优化模式初始场中的降水大尺度背景场,并分析此方法对此次降水过程模拟效果的影响。结果表明:两次试验模拟的降水分布特征总体一致,与GPM观测结果相比都存在一定的偏差,同化探空资料后初始场中200 hPa南亚高压、500 hPa高空槽和高空急流等大尺度环流背景均有所增强,中尺度暖低压和水汽输送特征也得到一定程度的加强,为降水的形成和发展提供了更有利的条件。降水的TS及ETS评分有明显提高(分别提高了约0.1和0.08),降水最强时刻中尺度系统的动力和热力结构均有不同程度的增强,这些结果对改进沙漠地区降水预报提供了有益的科学参考。

关键词: 强降水过程, 探空资料, 数值模拟, 同化, 腾格里沙漠

Abstract:

Precipitation is the primary source of soil moisture in arid and semi-arid regions, making accurate forecasting vital for water resource management and disaster prevention. This study investigates a precipitation event in the Tengger Desert to address the challenges posed by sparse observational data and significant errors in reanalysis data over desert areas. By assimilating radiosonde observations, the initial large-scale background conditions are improved. The findings demonstrate that although both experiments accurately capture the overall precipitation distribution pattern, discrepancies remain when compared with GPM observations. Radiosonde data assimilation enhances key circulation features, such as the 200 hPa South Asian High, the 500 hPa upper-level trough, and the upper-level jet stream. It also strengthens mesoscale warm low-pressure systems and moisture transport, creating conditions more conducive for precipitation development. This enhancement is evidenced by increased TS and ETS scores (approximately 0.1 and 0.08, respectively) and a better representation of mesoscale system dynamics and thermodynamics during peak precipitation, providing valuable scientific insights for precipitation forecasting in desert regions.

Key words: intense precipitation process, sounding data, numerical simulation, assimilation, Tengger Desert