of Geophysical Research : Atmospheres Evaporation in action sensed bymultiwavelength Doppler radars
of Geophysical Research : Atmospheres Evaporation in action sensed bymultiwavelength Doppler radars
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地球物理研究：多波长多普勒雷达感测大气蒸发
DOI：
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发表时间：
2017
期刊：
影响因子：
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通讯作者：
Daniel Watters
中科院分区：
文献类型：
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作者：
F. Tridon;A. Battaglia;Daniel Watters
这项工作记录了2011年9月15日在俄克拉荷马州的大气辐射测量站发生的以蒸发为主的降雨情况。最近开发的算法，适用于雷达多普勒频谱测量在Ka和W波段，提供了垂直演变的分箱液滴尺寸分布（DSDs）和垂直风。这些检索的数量与相对湿度（RH）的配置文件，以获得蒸发率和大气冷却率。此外，在区域的平稳性和小雨，当其他微物理过程可以忽略不计，所提出的案例研究表明，检索RH配置文件的垂直演变的液滴尺寸分布的可能性。关键是要描述连续水平之间雨团通量的梯度。这样的信号特别弱，并且由于在大约5分钟和250米（八个距离门）上检索的DSD的基本平均，可以增强。在相对湿度差为10%的范围内，推导出的轮廓与从符合的拉曼激光雷达观测的反演一致。这些结果表明，其他雨微物理过程可以通过结合雷达为基础的DSD反演辅助RH观测。
This work documents a rain case dominated by evaporation which occurred at the Atmospheric Radiation Measurement site in Oklahoma on 15 September 2011. A recently developed algorithm, applied to radar Doppler spectra measured at Ka and W band, provides the vertical evolution of binned drop size distributions (DSDs) and of the vertical wind. Such retrieved quantities are used in connection with relative humidity (RH) profiles to derive evaporation rates and atmospheric cooling rates. In addition, in regions of stationarity and of light rain, when other microphysical processes are negligible, the presented case study suggests the possibility of retrieving RH profiles from the vertical evolution of the drop size distributions. The key is to characterize the gradient of the rain mass flux between successive levels. Such signal is particularly weak and can be enhanced thanks to a substantial averaging of the retrieved DSD over approximately 5 min and 250 m (eight range gates). The derived profile agrees with the retrieval from coincident Raman lidar observations within a 10% RH difference. These results suggest that other rain microphysical processes could be studied by combining the radar-based DSD retrieval with ancillary RH observations.