Microwave radiometer observations of interannual water vapor variability and vertical structure over a tropical station
Microwave radiometer observations of interannual water vapor variability and vertical structure over a tropical station
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DOI：
10.1002/2014jd022838
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发表时间：
2015-05
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影响因子：
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通讯作者：
R. Renju;C. Suresh Raju;N. Mathew;Tinu Antony;K. Krishna Moorthy
中科院分区：
文献类型：
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作者：
R. Renju;C. Suresh Raju;N. Mathew;Tinu Antony;K. Krishna Moorthy
利用连续多年、多频微波辐射计廓线仪（MRP）观测资料，研究了位于印度半岛西南部的热带海岸站特里凡得琅（TVM）大气水汽的季节内、年际特征和垂直分布。通过与基于GPS湿延迟分量与PWV回归模型的GPS共站观测值的PWV比较，证明了MRP估算可降水量（PWV）的准确性，特别是在长季风期。在冬季和前季风季节，观测到PWV的大的日变化和季节内变化。有大的年际变化PWV在季风期间，由于频繁的本地对流和夏季雷暴。在季风期间，较低的年际PWV变率归因于持续的风从海洋带来的水分，这个沿海站。然而，显着的年际湿度变率被认为是在2至6公里的高度，这是与站上的季风强度。在台站上空的季风爆发之前，在5公里以上的海拔地区，比湿度增加到5-10 g/kg，并在整个活跃期保持不变。
The intraseasonal and interannual characteristics and the vertical distribution of atmospheric water vapor from the tropical coastal station Thiruvananthapuram (TVM) located in the southwestern region of the Indian Peninsula are examined from continuous multiyear, multifrequency microwave radiometer profiler (MRP) measurements. The accuracy of MRP for precipitable water vapor (PWV) estimation, particularly during a prolonged monsoon period, has been demonstrated by comparing with the PWV derived from collocated GPS measurements based on regression model between PWV and GPS wet delay component which has been developed for TVM station. Large diurnal and intraseasonal variations of PWV are observed during winter and premonsoon seasons. There is large interannual PWV variability during premonsoon, owing to frequent local convection and summer thunderstorms. During monsoon period, low interannual PWV variability is attributed to the persistent wind from the ocean which brings moisture to this coastal station. However, significant interannual humidity variability is seen at 2 to 6 km altitude, which is linked to the monsoon strength over the station. Prior to monsoon onset over the station, the specific humidity increases up to 5–10 g/kg in the altitude region above 5 km and remains consistently so throughout the active spells.