热带平流层CO浓度准两年振荡的位相变化特征  

Phase Change in Quasi-biennial Oscillation in the Tropical Stratospheric Carbon Monoxide Concentration

作　　者：王春晓[1,2,3] 田文寿[1] 

机构地区：[1]兰州大学大气科学学院半干旱气候变化教育部重点实验室,兰州730000 [2]中国气象局河南农业气象保障与应用技术重点实验室,郑州450003 [3]河南省气象台,郑州450003

出　　处：《大气科学》2017年第2期275-288,共14页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金项目41575038;41175042;国家杰出青年科学基金项目41225018~~

摘　　要：利用2005~2014年10年的卫星微波临边探测仪(MLS)资料分析了热带平流层一氧化碳(CO)体积混合比的年际变率,发现热带平流层CO浓度的准两年振荡(QBO)在30 h Pa高度附近存在明显的位相变化特征。大气化学气候模式模拟结果表明,热带平流层CO的准两年振荡信号是化学和动力过程共同作用的结果,而动力作用主要是QBO引起的次级经向环流引起的物质传输。化学和动力过程共同作用导致热带平流层CO浓度的垂直梯度在30 h Pa高度处发生反转,进而产生一氧化碳QBO信号的位相变化。此外,化学气候模式模拟结果还表明,与CO有关的化学过程不但可以减弱一氧化碳QBO信号的振幅,还可以在热带30~10 h Pa高度范围内造成一氧化碳QBO和纬向风QBO信号之间约3个月的时间差。The MLS（Microwave Limb Sounder） satellite observations of carbon monoxide（CO） mixing ratios from 2005 to 2014 have been analyzed to study the inter-annual variation of carbon monoxide（CO） in the tropical stratosphere.The results show that the quasi-biennial oscillation（QBO） in the tropical stratospheric CO mixing ratios has a phase change at 30 h Pa.The results from a chemistry–climate model show that the CO QBO is primarily resulted from combined effects of dynamical and chemical processes associated with CO,while the dynamical process is mainly associated with the transport of CO by the QBO-induced meridional circulation.The combined effects of dynamical and chemical processes lead to a reverse of the CO vertical gradient in the tropical stratosphere at 30 h Pa.Consequently,the CO QBO exhibits a phase change around this level.The model results also show that the chemical processes associated with CO not only have a weakening effect on the amplitude of the CO QBO,but also lead to a QBO phase difference by 3 months between zonal wind QBO and CO QBO at 10–30 h Pa.

关 键 词：平流层 一氧化碳(CO) 准两年振荡(QBO) 全球化学气候模式(WACCM) 位相变化 

分 类 号：P421.32[天文地球—大气科学及气象学]