亚热带北海地区海平面气压准两年振荡的变化趋势研究

发布时间：2018-08-10 17:33

【摘要】：由于海平面气压的变化对气温、降水、风场等气候要素具有显著影响,因此针对亚热带北海地区海平面气压准两年振荡的变化趋势进行研究,不仅对预测亚热带北海地区未来天气气候的变化具有指导作用,还对研究亚热带北海地区环流形成具有重要的参考价值,但是采用当前方法对亚热带北海地区海平面气压准两年振荡的变化趋势进行研究时,难以对北海地区海平面气压准两年振荡的显著性进行检验,存在耦合信号分辨能力较差的问题,且对信号的识别具有一定的局限性。为此,提出一种基于小波变换的亚热带北海地区海平面气压准两年振荡的变化趋势研究方法。该方法先利用小波功率谱对亚热带北海地区海平面气压信号进行检验,计算白噪声理论功率谱来实现亚热带北海地区海平面气压信号小波能量密度的显著性检验,在此基础上通过对1950年到2014年共64年的亚热带北海地区各个季节的气压做经验正交函数(EOF)分析,确定北海地区海平面气压的振荡周期的变化趋势。实验结果表明,所提方法能够有效提高耦合信号的分辨能力,为研究亚热带北海地区天气过程提供重要的理论依据。
[Abstract]:Because the change of sea level pressure has significant influence on the climatic factors such as temperature, precipitation and wind field, the variation trend of quasi-biennial oscillation of sea level pressure in the subtropical North Sea is studied. It not only has a guiding role in predicting the future changes of weather and climate in the subtropical North Sea region, but also has an important reference value for studying the formation of circulation in the subtropical North Sea region. However, it is difficult to test the significance of the quasi-biennial oscillation of sea level pressure in the North Sea region when the current method is used to study the variation trend of the quasi-biennial oscillation of sea level pressure in the subtropical North Sea. There is a problem of poor resolution of coupled signals, and there are some limitations to signal recognition. This paper presents a wavelet transform based approach to study the variation trend of sea level pressure quasi biennial oscillation in the subtropical North Sea. Firstly, the wavelet power spectrum is used to test the sea level pressure signal in the subtropical North Sea region, and the white noise theoretical power spectrum is calculated to test the significance of the wavelet energy density of the sea level pressure signal in the subtropical North Sea region. Based on the empirical orthogonal function (EOF) analysis of the sea pressure in the subtropical North Sea region for 64 years from 1950 to 2014, the variation trend of the oscillation period of sea level pressure in the North Sea region is determined. The experimental results show that the proposed method can effectively improve the resolution of coupled signals and provide an important theoretical basis for the study of weather processes in the subtropical North Sea region.
【作者单位】：北海市气象局;南京信息工程大学大气科学学院;
【分类号】：P732

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