Publication Date:
2019-04-08
Description:
The lowest region of the troposphere is a turbulent layer denominated Atmospheric Boundary Layer (ABL) characterized by high daily variability due to the influence of surface forcings. This is the reason why detecting systems with high spatial and temporal resolution, like lidars, have been widely applied for researching this region. In this paper, we present a comparative analysis on the use of lidar backscattered signals at three wavelengths (355, 532 and 1064 nm) to study the ABL investigating the high-order moments, which give us information about the ABL height (derived by the variance method), aerosol layers movements (skewness) and mixing conditions (kurtosis) at several heights. Previous studies have shown that 1064-nm wavelength, due to the predominance of particle signature in the total backscattered atmospheric signal, provides an appropriate description of the turbulence field and thus, in this study, it was considered as a reference. We analyze two case studies, which show us that the backscattered signal at 355 nm, even after applying some corrections, has a limited applicability for turbulence studies using the proposed methodology due to the strong contribution of the molecular signature to the total backscatter signal. This increases the noise associated to the profiles and, consequently, generates misinformation. On the other hand, the information on the turbulence field derived from the backscattered signal at 532 nm is similar to that obtained at 1064 nm due to the appropriate attenuation of the noise, generated by molecular component of backscattered signal, by the application of the corrections proposed.
Electronic ISSN:
1867-8610
Topics:
Geosciences
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