Long-term measurements of refractive index structure constant in atmospheric boundary layer

2012 ◽  
Author(s):  
Otakar Jicha ◽  
Pavel Pechac ◽  
Stanislav Zvanovec ◽  
Martin Grabner ◽  
Vaclav Kvicera
Keyword(s):  
Boundary Layer ◽  
Refractive Index ◽  
Atmospheric Boundary Layer ◽  
Structure Constant ◽  
Index Structure

scholarly journals Turbulence Detection in the Atmospheric Boundary Layer using Coherent Doppler Wind Lidar and Microwave Radiometer

2021 ◽  
Author(s):  
Pu Jiang ◽  
Jinlong Yuan ◽  
Kenan Wu ◽  
Lu Wang ◽  
Haiyun Xia
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Spatial Resolution ◽  
Microwave Radiometer ◽  
Structure Constant ◽  
New Method ◽  
Index Structure ◽  
Wind Lidar ◽  
Temporal And Spatial ◽  
Doppler Wind Lidar

Abstract. The refractive index structure constant (Cn2) is a key parameter in describing the influence of turbulence on laser transmission in the atmosphere. A new method for continuous Cn2 profiling with both high temporal and spatial resolution is proposed and demonstrated. Under the assumption of the Kolmogorov “2/3 law”, the Cn2 profile can be calculated by using the wind field and turbulent kinetic energy dissipation rate (TKEDR) measured by coherent Doppler wind lidar (CDWL) and other meteorological parameters derived from microwave radiometer (MWR). In the horizontal experiment, a comparison between the results from our new method and measurements made by a large aperture scintillometer (LAS) is conducted. Except for the period of stratification stabilizing, the correlation coefficient between them in the six-day observation is 0.8389, the mean error and standard deviation is 1.09 × 10−15 m−2/3 and 2.14 × 10−15 m−2/3, respectively. In the vertical direction, the continuous observation results of Cn2 and other turbulence parameter profiles in the atmospheric boundary layer (ABL) are retrieved. More details of the atmospheric turbulence can be found in the ABL owe to the high temporal and spatial resolution of MWR and CDWL (spatial resolution of 26 m, temporal resolution of 147 s).

Estimating local seeing at Observatorio Astronómico Nacional in San Pedro Mártir using CFD simulations of the atmospheric boundary layer

2020 ◽  
Vol 496 (4) ◽  
pp. 5552-5563
Author(s):  
R Sánchez García ◽  
M G Richer ◽  
R Gómez Martínez ◽  
R Avila
Keyword(s):  
Boundary Layer ◽  
Wind Speed ◽  
Atmospheric Boundary Layer ◽  
Vertical Profile ◽  
Structure Constant ◽  
Index Of Refraction ◽  
San Pedro ◽  
Computational Fluid Dynamics Simulations ◽  
Dynamics Simulations ◽  
Sierra San Pedro Martir

ABSTRACT We present computational fluid dynamics simulations of the atmospheric boundary layer (ABL) at the Observatorio Astronómico Nacional in the Sierra San Pedro Mártir (OAN-SPM) whose objective is to model the seeing observed at the site. We constrain the simulations using observations of the seeing, the vertical profile of the wind speed, and the vertical profile of the temperature, the first two resolved as a function of wind direction. We successfully model the seeing observed under typical wind conditions for each direction by adopting input profiles of the wind speed, the turbulent kinetic energy, and the energy dissipation. The resulting vertical profiles of the index of refraction structure constant are qualitatively similar to the mean profile derived from studies at the site.

Estimates of the Refractive Index and Regular Refraction of Optical Waves in the Atmospheric Boundary Layer: Part 2, Laser Beam Refraction

2018 ◽  
Vol 31 (5) ◽  
pp. 445-450 ◽  
Author(s):  
S. L. Odintsov ◽  
V. A. Gladkikh ◽  
A. P. Kamardin ◽  
V. P. Mamyshev ◽  
I. V. Nevzorova
Keyword(s):  
Boundary Layer ◽  
Refractive Index ◽  
Laser Beam ◽  
Atmospheric Boundary Layer ◽  
Optical Waves

scholarly journals Determination of the Structural Characteristic of the Refractive Index of Optical Waves in the Atmospheric Boundary Layer with Remote Acoustic Sounding Facilities

Atmosphere ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 711 ◽  
Author(s):  
Odintsov ◽  
Gladkikh ◽  
Kamardin ◽  
Nevzorova
Keyword(s):  
Experimental Data ◽  
Boundary Layer ◽  
Refractive Index ◽  
Atmospheric Boundary Layer ◽  
Structural Characteristic ◽  
Structural Characteristics ◽  
Acoustic Sounding ◽  
Optical Waves ◽  
Ultrasonic Anemometer

The structural characteristic of the refractive index of optical waves was calculated from experimental data on the microstructure of the temperature turbulence in the atmospheric boundary layer. The experimental data were obtained with an acoustic meteorological radar (sodar), ultrasonic anemometer–thermometer, and meteorological temperature profilometer. Estimates of the structural characteristics for different conditions in the atmospheric boundary layer are presented and were compared with model profiles.

scholarly journals Finescale Clusterization Intermittency of Turbulence in the Atmospheric Boundary Layer

2020 ◽  
Vol 77 (7) ◽  
pp. 2375-2392
Author(s):  
Lei Liu ◽  
Fei Hu
Keyword(s):  
Boundary Layer ◽  
Atmospheric Boundary Layer ◽  
Return Time ◽  
Statistical Simulation ◽  
Convective Boundary ◽  
Wind Speeds ◽  
Stable Conditions ◽  
Telegraphic Approximation ◽  
Better Than

AbstractThe intermittency of atmospheric turbulence plays an important role in the understanding of particle dispersal in the atmospheric boundary layer and in the statistical simulation of high-frequency wind speed in various applications. There are two kinds of intermittency, namely, the magnitude intermittency (MI) related to non-Gaussianity and the less studied clusterization intermittency (CI) related to long-term correlation. In this paper, we use a 20 Hz ultrasonic dataset lasting for 1 month to study CI of turbulent velocity fluctuations at different scales. Basing on the analysis of return-time distribution of telegraphic approximation series, we propose to use the shape parameter of the Weibull distribution to measure CI. Observations of this parameter show that contrary to MI, CI tends to weaken as the scale increases. Besides, significant diurnal variations, showing that CI tends to strengthen during the daytime (under unstable conditions) and weaken during the nighttime (under stable conditions), are found at different observation heights. In the convective boundary layer, the mixed-layer similarity is found to scale the CI exponent better than the Monin–Obukhov similarity. At night, CI is found to vary less with height in the regime with large mean wind speeds than in the regime with small mean wind speeds, according to the hockey-stick theory.

Estimating refractive index structure constant and extinction coefficient under misalignment

Optik ◽  
2020 ◽  
Vol 206 ◽  
pp. 164182
Author(s):  
Dagang Jiang ◽  
Ting Lyu ◽  
Xin Liu ◽  
Yishuai Yuan ◽  
Bin Zhu
Keyword(s):  
Refractive Index ◽  
Extinction Coefficient ◽  
Structure Constant ◽  
Index Structure
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