Impact of quasi-biennial oscillation on the inter-annual variability of the tropopause height and temperature in the tropics: A study using COSMIC/FORMOSAT-3 observations
Impact of quasi-biennial oscillation on the inter-annual variability of the tropopause height and temperature in the tropics: A study using COSMIC/FORMOSAT-3 observations
复制标题
DOI：
10.1016/j.atmosres.2013.12.014
复制
发表时间：
2014-03
影响因子：
5.5
通讯作者：
V. Kumar;S. Dhaka;K. Reddy;A. Gupta;S. Prasad;V. Panwar;Narendra Singh;S. Ho;M. Takahashi
中科院分区：
文献类型：
--
作者：
V. Kumar;S. Dhaka;K. Reddy;A. Gupta;S. Prasad;V. Panwar;Narendra Singh;S. Ho;M. Takahashi
利用COSMIC/FORMOSAT-3卫星的射电掩星观测，研究了准两年一次振荡（QBO）对对流层冷点顶温度（T-CPT）和对流层顶高度（H-CPT）的影响。利用935863次掩星观测资料，研究了2007年1月至2011年12月T-CPT和H-CPT的纬向平均季节变化。结果显示在30°N-30°S地理纬度。一般来说，T-CPT在2月最冷，在8月最暖。H-CPT在12月至2月达到最高高度，在7月至8月达到最低高度。有趣的是，在两个半球的所有季节中，H-CPT在赤道外区域（约20°N或20°S）都显示出最大值。相对于赤道地区，赤道外地区冬季的H-CPT （~ 1.0 km）略高于北半球季风季节的H-CPT （~ 0.5 km）。T-CPT和H-CPT年际变化明显受QBO的影响。西风（东风）相产生暖（冷）T-CPT， H-CPT减少（增加）。QBO可诱导T-CPT变化2°C， H-CPT变化0.5 km。
The effect of quasi-biennial oscillation (QBO) on the temperature of cold point tropopause (T-CPT) and its height (H-CPT) is being investigated using radio occultation measurements by COSMIC/FORMOSAT-3. Observations comprising of 935,863 numbers of occultations have been used to study the zonal mean seasonal variability in T-CPT and H-CPT from January 2007 to December 2011. Results are shown over 30°N–30°S geographic latitudes. In general, T-CPT is found to be the coldest in February and the warmest in August. H-CPT attains maximum height during December–February and minimum during July–August. Interestingly, H-CPT shows maxima at off-equator region (around 20°N or 20°S) during all the seasons in both hemispheres. H-CPT at off-equatorial region, in reference to the equatorial region, is slightly higher (~ 1.0 km) during winter as compared to monsoon season (~ 0.5 km) in Northern Hemisphere (NH). Inter-annual variation in T-CPT and H-CPT found to be clearly influenced by the QBO. Westerly (easterly) phase generates warm (cold) T-CPT, which consequently results a decrease (increase) in H-CPT. It is concluded that QBO induces the changes in T-CPT by as much as 2 °C and in H-CPT by 0.5 km.