L波段探空秒级资料稀疏化方案及检验方法
A Sparsification Scheme and Evaluation of the L-Band Radiosonde High-Resolution Data
中文摘要：
高垂直分辨率探空资料的稀疏化是资料同化应用过程中非常重要的技术环节。通过甄别L波段秒级探空不同气象要素的时空变化拐点，提出一套自适应的稀疏化方案。该方案可以显著增加温度、湿度、风特性层数目，使得单次探空廓线的层数较现行台站业务软件提供的多近200%，既能精准地描述气象要素垂直变化特征，又能有效地被再分析同化系统应用。应用基于模式背景场（ERA-Interim再分析资料）的观测资料偏差评估技术，通过对比分析不同来源的探空要素数据量、偏差（Bias）和均方根误差（RMSE）等指标，对稀疏化方案的效果进行了量化检验。结果表明：该稀疏化方案不仅实现了再分析同化应用过程中的探空廓线层数的显著增加，而且其Bias和RMSE的大小及垂直分布较已有整合廓线数据更合理。该稀疏化方案为更有效地将我国高垂直分辨率L波段探空资料应用于大气再分析提供了必要保证。
中文关键词：
秒级探空，稀疏化，量化检验，再分析，同化
KeyWords：
second-level radiosonde, sparsification, quantitative evaluation, reanalysis, assimilation
Abstract：
This paper puts forward a suitable sparsification scheme for L-band second-level radiosonde data. The sounding vertical profile may describe more accurately the vertical change of meteorological elements with increased number of the significant layers. The background field (ERA-Interim reanalysis) is applied for bias evaluation of the observation data. Sounding data from different sources are utilized for comparison and analysis. The bias, the root mean square error (RMSE) and other quantitative indicators are calculated to assess the effect of the sparsification scheme. The results show that this scheme can not only increase the numbers of the radiosonde profile levels, but also achieve better Bias and RMSE results. This scheme may provide necessary guarantee for the assimilation applications of the high-resolution L-band radiosonde data in China for the future.