北冰洋80°～85°N浮冰区对流层大气的垂直结构   总被引：4，自引：2，他引：2       下载免费PDF全文

马永锋  卞林根  周秀骥  逯昌贵  窦挺峰  汤洁 《海洋学报》2011,33(2):48-59

利用2008年夏季中国第3次北冰洋考察所获取的GPS探空资料对北冰洋(79°～85.5°N,144°～170°W)浮冰区对流层大气的垂直结构进行了研究.结果表明:北冰洋浮冰区对流层中部大气的平均温度递减率为6.47℃/km;对流层顶高度为8.0～10.7 km,平均为9.3 km,对流层顶温度为-59.4～-43.5℃...  相似文献   

东亚地区夏季风活动与对流层顶臭氧含量变化的关系探讨   总被引：2，自引：0，他引：2  

郭世昌  刘佳  吕达仁  李跃清  戴敏  李琼 《云南地理环境研究》2007,19(6):1-6,12

利用1976～2001年东亚地区的风场、气压场和对流层顶臭氧浓度观测资料,选取并计算了3种当前使用较为广泛的东亚季风指数,分析了夏季期间上述指数与对流层顶臭氧的相关,从而对东亚地区季风活动与对流层顶臭氧含量分布的关系进行了探讨.分析表明:(1)东亚SMI夏季风指数的强弱与西太平洋副热带高压区的对流层顶臭氧之间存在着正相关,且相关性较好;(2)指数EAMI与对流层顶臭氧存在相关,具体表现为在南海热带季风区存在着负相关、在大陆--日本副热带季风区存在正相关、西太平洋副热带高压区存在较好的正相关;(3)而在副热带梅雨锋区,EASMI指数的强弱与对流层顶臭氧含量变化存在较好的正相关,在热带季风槽区,EASMI指数的强弱与对流层顶臭氧含量变化存在较好的负相关.  相似文献   

Wind fluctuations near a cold vortex-tropopause funnel system observed by the MU radar     

Shoichiro Fukao  Manabu D. Yamanaka  Hiromasa Matsumoto  Toru Sato  Toshitaka Tsuda  Susumu Kato 《Pure and Applied Geophysics》1989,130(2-3):463-479

Vertical and temporal variations of three-dimensional wind velocity associated with an upper-tropospheric cold vortex-tropopause funnel system were observed by an MST radar in Japan (the MU radar). Marked changes of vertical velocity and horizontal wind direction were found between the inside and outside of the cold vortex. The vertical velocity activity outside the vortex was asymmetric; it was most active in a sector before the vortex. Unsaturated internal gravity waves in their generation stage contribute predominantly to the vertical velocity activity, suggesting that tropospheric occluded cyclones may be a possible source of middle-atmospheric gravity waves through the geostrophic adjustment process.  相似文献   

2019年4月广州白云机场持续暴雨前对流层顶和平流层异常信号分析          下载免费PDF全文

郭智亮  刘娟  张有洋  张军  高聪晖  陈淑敏 《中低纬山地气象》2022,46(1):39-44

利用欧洲中心ERA5再分析资料和广州白云机场自动观测系统降水资料,分析2019年4月白云机场持续暴雨前对流层顶和平流层的信号特征。分析发现,2019年4月中下旬,广州白云机场出现了3次持续时间长、降水量大的持续性暴雨过程,降水较往年同期显著偏多。研究结果表明,3次持续暴雨发生前,对流层顶高度出现了下降,平流层高位涡冷空气入侵,机场上空位涡升高;在环流场中,中低纬地区对流层顶和平流层东风偏强,向北和向下传播,广州白云机场终端区在暴雨发生前西风持续下传;广州白云机场上空暴雨发生前对流层顶至平流层位势高度正异常。暴雨发生前,平流层冷空气高位涡移入、对流层顶下降、西风的下传均有利于持续性暴雨的生成。  相似文献   

Trends of Lower-to Mid-Stratospheric Water Vapor Simulated in Chemistry-Climate Models          下载免费PDF全文

HU Ding-Zhu  HAN Yuan-Yuan  SANG Wen-Jun  XIE Fei 《大气和海洋科学快报》2015,8(1):57-62

Using the outputs from 16 chemistry-climate models(CCMs), the trends of lower- to mid-stratospheric water vapor(WV) during the period 1980–2005 were studied. Comparisons were made between the CCM results and European Centre for Medium-Range Weather Forecasts(ECMWF) Interim Reanalysis(ERA-Interim).The results of most of the CCMs, and those based on ERA-Interim, showed the trends of lower- to mid-stratospheric WV during the period 1980–2005 to be positive, with the extent of the trend increasing with altitude. The trend of lower- to mid-stratospheric WV in the ensemble mean of the CCMs was 0.03 ppmv per decade,which was about twice as large as that based on ERA-Interim. The authors also used a state-of-the-art general circulation model to evaluate the impacts of greenhouse gas(GHG) concentration increases and ozone depletion on stratospheric WV. The simulation results showed that the increases of lower- to mid-stratospheric WV affected by the combined effects of GHG and ozone changes happened mainly via warming of the tropopause and enhancement of the Brewer-Dobson circulation(BDC), with the former being the greater contributor.GHG increase led to a higher and warmer tropopause with stronger BDC, which in turn led to more WV entering the stratosphere; while ozone depletion led to a higher and cooler tropopause, which caused the decreases of lowerto mid-stratospheric WV, despite also causing stronger BDC.  相似文献   

Potential vorticity and the PV perspective   总被引：5，自引：0，他引：5  

Brian HOSKINS 《大气科学进展》2015,32(1):2-9

This paper highlights some theoretical aspects of potential vorticity(PV) and discusses some of the insights the PV perspective has given us. The topics covered include the nature of PV, its controlling role in the symmetric stability of the atmosphere, its inversion to give the flow field, Rossby waves and their coupling to give baroclinic instability, PV and midlatitude weather systems and, finally, insights into tropical motions.  相似文献   

青藏高原及其邻近区域穿越对流层顶质量通量的时空演变特征   总被引：15，自引：6，他引：9  

樊雯璇  王卫国  卞建春 《大气科学》2008,32(6):1309-1318

利用1958~2001年ECMWF资料, 根据Wei公式估算了青藏高原及其邻近区域穿越对流层顶的质量通量 (CTF), 分析了CTF的时空分布特征。分析结果表明: (1) CTF分布呈现纬向型, 在副热带西风急流北侧即对流层顶断裂带中存在东西向的TST (对流层向平流层输送)[CD*2]STT (平流层向对流层输送)[CD*2]TST的波列结构 (水平输送项决定), 而南侧分布决定于垂直输送项。 (2) 在80°E~105°E范围内, 冬春季节, 青藏高原南部及其以南区域为TST, 北部为STT; 夏秋季节, 整个区域几乎由TST所控制。西风急流南侧的CTF主要决定于垂直项, 而北侧主要决定于水平项, 再往北, 垂直项与水平项贡献相当。 (3) 青藏高原与孟加拉湾区域平均CTF在所有季节均为TST, 即有从对流层到平流层净的向上输送, 2月强度最大, 7月为另一个极大值; 两个极大值有不同的产生机制, 后者决定于垂直项, 而前者由水平项决定。 (4) 青藏高原 (及孟加拉湾) 区域年平均CTF在1958~2001年之间的变化趋势在1982年左右出现一个转折: 1982年之前, CTF为递减过程; 而之后CTF为相对较强的增长。上述结果表明: 尽管冬季高原上空为下沉气流, 但高原上空的水平输送项有很强的向上贡献, 这与丛春华等 (2003) 得出的STT不一致。但需要指出的是, 根据Wei公式计算的CTF, 〖JP2〗尤其在急流附近, 对资料中存在的误差十分敏感 (Gettleman等, 2000), 因此青藏高原主体上空在冬季是STT还是TST, 有待于进一步的分析研究。  相似文献   

北极楚克奇海上空臭氧垂直变化的探测与分析   总被引：2，自引：0，他引：2  

周立波  邹捍  刘宇 《气候与环境研究》2002,7(4):409-414

1999年夏季,中国首次组织北极地区科学考察.分析此次考察中楚克奇海海域上空获得的大气结构和臭氧探空资料,结合臭氧总量观测光谱仪(TOMS)臭氧总量和NCEP大气环流资料,指出:考察期间楚克奇海海域上空臭氧总量与13 km以下臭氧含量关系密切,而在20 km附近最大臭氧浓度处的臭氧变化与大气臭氧总量关系较差,表明整层臭氧总量的变化主要受低层大气臭氧变化的影响.大气臭氧总量呈高-低-高变化,对流层顶高度呈低-高-低变化,分析500hPa高度场表明:考察期间的天气系统可能是造成局地臭氧变化的主要原因.  相似文献   

Statistics of the tropopause inversion layer over Beijing   总被引：2，自引：0，他引：2  

卞建春  陈洪滨 《大气科学进展》2008,25(3):381-386

High resolution radiosonde data from Beijing, China in 2002 are used to study the strong tropopause inversion layer （TIL） in the extratropical regions in eastern Asia. The analysis, based on the tropopause- based mean （TB-mean） method, shows that the TIL over Beijing has similar features as over other sites in the same latitude in Northern America. The reduced values of buoyancy frequency in 13-17 km altitude in winter-spring are attributed to the higher occurrence frequency of the secondary tropopause in this season. In the monthly mean temperature profile relative to the secondary tropopause, there also exists a TIL with somewhat enhanced static stability directly over the secondary sharp thermal tropopause, and a 4 km thickness layer with reduced values of buoyancy frequency just below the tropopause, which corresponds to the 13-17 km layer in the first TB-mean thermal profile. In the monthly mean temperature profile relative to the secondary tropopause, a TIL also exists but it is not as strong.
For individual cases, a modified definition of the TIL, focusing on the super stability and the small distance from the tropopause, is introduced. The analysis shows that the lower boundary of the newly defined TIL is about 0.42 km above the tropopause, and that it is higher in winter and lower in summer; the thickness of the TIL is larger in winter-spring.  相似文献   

1964—2005年辽宁第一对流层顶温度变化特征分析   总被引：3，自引：1，他引：2  

蔡福  李辑 《气象与环境学报》2007,23(4):18-24

利用趋势分析、突变分析及小波分析方法对1964—2005年辽宁南部(大连)和北部(沈阳)第一对流层顶温度特征进行分析和比较。结果表明:近42 a,对于辽宁地区第一对流层顶温度,年、夏秋季平均值均呈升高趋势,春冬季平均值呈弱下降趋势;多年平均值的年变化表现为北部夏季最高、春季最低,南部秋季最高、春季最低;南部年、季的年际变化幅度均大于北部;年际变化幅度在南部夏季最大、春秋季次之、冬季最小,在北部夏季最大、冬季次之、春秋季差异不大;发生突变时段春夏季南部滞后于北部。在春季存在着3 a,6 a和18 a周期,其他季节周期变化南部较北部明显。  相似文献