亚热带北海地区海平面气压准两年振荡的变化趋势研究

Design of Text Information Mining System in Large Data Environment

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。

Due to precipitation change in sea level pressure on air temperature,wind and other climaticfactors,has significant effect,so in subtropical Beihai area of sea level pressure change trend of quasibiennial oscillation of the study,not only has a guiding role for the prediction of subtropical weather inBeihai Province in the future climate change,but also has important reference value for the study of thesubtropical area of Beihai ring study the change trend of manifold,but the current method of subtropicalarea of Beihai sea level pressure of the quasi biennial oscillation,it is difficult for the Beihai sea levelpressure QBO significant test,there is coupling signal resolution ability is poor,and the recognition ofthe signal with aCertain limitations.Therefore,a subtropical area of Beihai sea level pressure based onthe wavelet transform of the quasi biennial oscillation methods trend changes.The method uses waveletpower spectrum to inspect the subtropical area of Beihai sea level pressure signal,the construction andtheoretical comparison of white noise of spectrum to achieve a significant test of subtropical Beihai sealevel pressure signal wavelet energy density,based on the pressure by1950to2014a total of64years in Beihai subtropical each season do empirical orthogonal function(EOF)analysis,determine theoscillation period of the northern Haiti area for sea level pressure.The experimental results show that the,The proposed method can effectively improve the resolution of the coupled signals,and provides animportant theoretical basis for the study of the weather process in the subtropical Beihai.