Detection of mixing layer depth with ceilometer

CHEN Zhen-yi; LIU Wen-qing; ZHANG Yu-jun; ZHANG Chun-guang; RUAN Jun; HE Jun-feng

doi:10.3969/j.issn.1001-3806.2009.05.022

In order to study the methods of determining the height of the mixing layer,some important methods,such as visual inspection and gradient method,were analyzed.A novel method,namely the Steyn method,was put forward.After describing its basic principle,its ideal model was given out.It was emphasized how the initial value affected the fit result.Then the signals(the profile of aerosol backscatter coefficient and height)obtained from the ceilomter Vaisala CL31 were fitted and the height of the mixing layer was obtained.The results show that with the Steyn method,some information,such as the mixing layer height and the entrainment depth,can be obtained accurately no matter the backscatter vertical distribution varies greatly or the mixing layer is very shallow.The spatial and time distribution of the mixing layer height agrees with the theoretical prediction very well.

Detection of mixing layer depth with ceilometer

Corresponding author: LIU Wen-qing, wqliu@aiofm.ac.cn;

1. Key Laboratory of Environmental Optics & Technology, Anhui Institute of Optics & Fine Mechanics, Chinese Academy ofSciences, Hefei 230031, China

Received Date: 2008-06-06

Accepted Date: 2008-07-31

Available Online: 2009-10-25

Abstract: In order to study the methods of determining the height of the mixing layer,some important methods,such as visual inspection and gradient method,were analyzed.A novel method,namely the Steyn method,was put forward.After describing its basic principle,its ideal model was given out.It was emphasized how the initial value affected the fit result.Then the signals(the profile of aerosol backscatter coefficient and height)obtained from the ceilomter Vaisala CL31 were fitted and the height of the mixing layer was obtained.The results show that with the Steyn method,some information,such as the mixing layer height and the entrainment depth,can be obtained accurately no matter the backscatter vertical distribution varies greatly or the mixing layer is very shallow.The spatial and time distribution of the mixing layer height agrees with the theoretical prediction very well.

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Reference (10)

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Detection of mixing layer depth with ceilometer

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