Oblique propagation of monsoon gravity waves during the northern hemisphere 2007 summer
Oblique propagation of monsoon gravity waves during the northern hemisphere 2007 summer
复制标题
DOI：
10.1002/2016jd026008
复制
发表时间：
2017-05
期刊：
影响因子：
--
通讯作者：
B. Thurairajah;D. Siskind;S. Bailey;J. Carstens;J. Russell;M. Mlynczak
中科院分区：
文献类型：
--
作者：
B. Thurairajah;D. Siskind;S. Bailey;J. Carstens;J. Russell;M. Mlynczak
我们结合卫星观测和高分辨率模式输出来理解季风对流是高纬度中层重力波(GWS)的来源。利用宽带发射辐射测量/热层电离层中层能量和动力学(SABER/TIMED)卫星温度探测资料和高分辨率海军全球大气预报系统-高级物理高空(NOGAPS/ALPHA)模式结果，分析了2007年夏季北半球季风区产生的GWS以及风在将这些GWS聚焦到高纬度中层大气中所起的作用。在平流层以上的NH层，季风GW动量通量(GWMF)表现出沿东风急流倾斜结构的极地倾斜。NH热带平流层GWMF时间序列与全球风的相关系数(>；0.5)也具有与东风急流一致的倾斜结构，证实了平流层季风GW折射为夏季东风急流并可到达高纬中层的模拟理论。由于极地中层云(PMC)是反映极地夏季中层变化的敏感指标，我们将热带平流层GWMF的时间序列与中层卫星云图和冰粒大小/大气资料得到的PMC出现频率(OF)进行比较，以评估这一波聚焦在中层的影响。高纬PMC与热带平流层GWMF呈显着正相关，表明季风GWS对高纬中间层有一定的影响。PMC季末相关不一致的原因是季风GWS对PMC的影响主要是由于准5天行星波增强所致。
We present a combination of satellite observation and high‐resolution model output to understand monsoon convection as a source of high‐latitude mesospheric gravity waves (GWs). The GWs generated over the Northern Hemisphere (NH) monsoon region during the 2007 summer and the role of the winds in focusing these GWs toward the high‐latitude middle atmosphere are analyzed using the Sounding of the Atmosphere using Broadband Emission Radiometry/Thermosphere Ionosphere Mesosphere Energetics and Dynamics (SABER/TIMED) satellite temperature data and the high‐resolution Navy Operational Global Atmospheric Prediction System‐Advanced Level Physics High Altitude (NOGAPS/ALPHA) model results. In the NH, above the stratosphere, the monsoon GW Momentum Flux (GWMF) exhibits a poleward tilt that follows the slanted structure of the easterly jet. The correlation coefficients (>0.5) between the time series of NH tropical stratospheric GWMF and the global winds also have a slanted structure that coincide with the easterly jet, confirming the modeling theory that stratospheric monsoon GWs are refracted into the summer easterly jet and can reach the high‐latitude mesosphere. Since Polar Mesospheric Clouds (PMCs) are sensitive indicators of changes in the polar summer mesosphere, we compared the time series of tropical stratospheric GWMF to the PMC occurrence frequency (OF) obtained from the Cloud Imaging and Particle Size/Aeronomy of Ice in the Mesosphere satellite data to assess the influence of this wave focusing in the mesosphere. There is a significant positive correlation between the high‐latitude PMC OF and the tropical stratospheric GWMF suggesting a definite influence of monsoon GWs on the high‐latitude mesosphere. The disagreement in correlation at the end of the PMC season is attributed to the enhancement of the quasi 5 day planetary wave dominating over the influence of monsoon GWs on PMCs.