Simultaneous observations of SAO and QBO in winds, temperature and ozone in the tropical middle atmosphere over Thumba (8.5°N, 77°E)
Simultaneous observations of SAO and QBO in winds, temperature and ozone in the tropical middle atmosphere over Thumba (8.5°N, 77°E)
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同时观测 Thumba 上空热带中层大气中的 SAO 和 QBO（8.5°N，77°E）的风、温度和臭氧
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
G. Ramkumar
中科院分区：
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作者：
K. K. Kumar;D. Swain;S. R. John;G. Ramkumar
由于中层大气的重要性，最近在2002-2007年期间在Thumba（北纬8.5度，东经77度）实施了中层大气动力学方案。该方案下的测量包括定期的无线电探空仪/火箭飞行以及大气雷达，提供了中层大气区域风和温度的长期观测，从中可以分析波和振荡及其强迫机制，特别是低纬度中层大气。然而，由于缺乏像臭氧这样对大气动力学有重要贡献的重要测量数据，对强迫机制的详细分析仍然不完整。目前，TIMED/SABER（热层、电离层、中间层能量学和动力学/利用宽发射辐射测量法探测大气层）卫星提供了自2002年以来多年来全球约15至100公里范围内的臭氧概况。在这方面，在MIDAS活动期间，利用TIMED/SABER的臭氧观测，对臭氧及其准两年振荡和半年振荡尺度的变化进行了全面研究。在使用TIMED/SABER的臭氧测量之前，已经与2007年南半球附加臭氧探测器活动在几个站点获得的臭氧现场测量结果进行了相互比较。相互比较表明，SABER和臭氧探测仪得出的臭氧廓线之间非常吻合。在验证了SABER观测结果之后，臭氧廓线被广泛用于研究QBO和SAO沿着20-100 km高度区域的温度和风。我们已经知道中间层和平流层的SAO处于相反的位相，但本研究首次报道了中间层本身的反位相方面。因此，本工作试图同时研究平流层和中间层的臭氧，温度和风的长周期振荡在这个纬度上的第一次。这些观测为同时探索中层大气化学、动力学和热结构的长期振荡提供了一个独特的机会。
Owing to the importance of middle atmosphere, recently, a Middle Atmospheric Dynamics (MIDAS) program was carried out during the period 2002–2007 at Thumba (8.5°N, 77°E). The measurements under this program, involving regular radiosonde/rocket flights as well as atmospheric radars, provided long period observations of winds and temperature in the middle atmospheric region from which waves and oscillations as well as their forcing mechanisms particularly in the low-latitude middle atmosphere could be analyzed. However, a detailed analysis of the forcing mechanisms remains incomplete due to the lack of important measurements like ozone which is a significant contributor to atmospheric dynamics. Presently, profiles of ozone are available from TIMED/SABER (Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics/Sounding of the Atmosphere using Broad Emission Radiometry) satellite globally from about 15 to 100 km, over multiple years since 2002. In this regard, a comprehensive study has been carried out on ozone and its variability at Quasi Biennial Oscillation (QBO) and Semiannual Oscillation (SAO) scales using TIMED/SABER ozone observations during the MIDAS campaign period. Before using the TIMED/SABER ozone measurements, an inter-comparison has been carried out with in situ measurements of ozone obtained under the Southern Hemisphere Additional Ozonesondes (SHADOZ) campaign for the year 2007 at few stations. The inter-comparison showed very good agreement between SABER and ozonesonde derived ozone profiles. After validating the SABER observations, ozone profiles are used extensively to study the QBO and SAO along with temperature and winds in the 20–100 km height region. It is known that the SAO in mesosphere and stratosphere are in opposite phases, but the present study for the first time reports the aspect of opposite phases in the mesosphere itself. Thus, the present work attempts to study the long-period oscillations in stratosphere and mesosphere in ozone, temperature and winds simultaneously for the first time over this latitude. These observations provided a unique opportunity to explore long-period oscillations in chemistry, dynamics and thermal structure of the middle atmosphere simultaneously.