Atmospheric Duct Detection Using Wind Profiler Radar and RASS

AbstractA method of detecting atmospheric ducts using a wind profiler radar (WPR) and a radio acoustic sounding system (RASS) is proposed. The method uses the RASS to measure the virtual temperature profile and calculate the Brunt–Väisälä frequency; it also uses the WPR to measure the spectral width of the atmosphere and the atmospheric refractive index structure constant. Then the profile of the atmospheric refractive index gradient and modified refractivity are calculated using virtual temperature, spectral width, and the atmospheric refractive index structure constant. Finally, the height and intensity of the atmospheric duct are calculated to achieve continuous monitoring of the atmospheric duct. To verify the height and intensity of the atmospheric duct, comparison experiments between WPR-RASS and radiosondes were carried out from June 2014 to June 2015 in Dalian, Liaoning Province, China. The results show that the profile of modified refractivity by WPR-RASS has exactly the same trend as the radiosondes, the two methods have a good consistency, and the atmospheric duct value from WPR-RASS is in good agreement with that from radiosondes.

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Analysis of Characteristics of Atmospheric Structure Constant of Refractive Index Based on Wind Profiler Radar in Precipitation

Lecture Notes in Electrical Engineering - Communications, Signal Processing, and Systems ◽

10.1007/978-981-13-6508-9_90 ◽

2019 ◽

pp. 745-752

Author(s):

Yating Li ◽

Debin Su ◽

Xingang Fan

Keyword(s):

Refractive Index ◽

Structure Constant ◽

Wind Profiler ◽

Atmospheric Structure ◽

Wind Profiler Radar

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Seasonal, annual and inter-annual features of turbulence parameters over the tropical station Pune (18°32' N, 73°51' E) observed with UHF wind profiler

Annales Geophysicae ◽

10.5194/angeo-26-3677-2008 ◽

2008 ◽

Vol 26 (12) ◽

pp. 3677-3692 ◽

Cited By ~ 5

Author(s):

Narendra Singh ◽

R. R. Joshi ◽

H.-Y. Chun ◽

G. B. Pant ◽

S. H. Damle ◽

...

Keyword(s):

Refractive Index ◽

Lower Troposphere ◽

Spectral Width ◽

Index Structure ◽

Wind Profiler ◽

Structure Parameter ◽

Post Monsoon ◽

Tropical Station ◽

Refractive Index Structure Parameter ◽

Turbulence Parameters

Abstract. The present study is specifically focused on the seasonal, annual and inter-annual variations of the refractive index structure parameter (Cn2) using three years of radar observations. Energy dissipation rates (ε) during different seasons for a particular year are also computed over a tropical station, Pune. Doppler spectral width measurements made by the Wind Profiler, under various atmospheric conditions, are utilized to estimate the turbulence parameters. The refractive index structure parameter varies from 10−17.5 to 10−13 m−2/3 under clear air to precipitation conditions in the height region of 1.05 to 10.35 km. During the monsoon months, observed Cn2 values are up to 1–2 orders of magnitude higher than those during pre-monsoon and post-monsoon seasons. Spectral width correction for various non-turbulent spectral broadenings such as beam broadening and shear broadening are made in the observed spectral width for reliable estimation of ε under non-precipitating conditions. It is found that in the lower tropospheric height region, values of ε are in the range of 10−6 to 10−3 m2 s−3. In summer and monsoon seasons the observed values of ε are larger than those in post-monsoon and winter seasons in the lower troposphere. A comparison of Cn2 observed with the wind profiler and that estimated using Radio Sonde/Radio Wind (RS/RW) data of nearby Met station Chikalthana has been made for the month of July 2003.

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Measurement and analysis of refractive index structure constant Cn2 profile over Delhi on diurnal and seasonal basis

MAUSAM ◽

10.54302/mausam.v64i2.693 ◽

2021 ◽

Vol 64 (2) ◽

pp. 363-370

Author(s):

M.I. ANSARI ◽

S.K. KUNDU ◽

K.C. SAIKRISHNAN ◽

RANJU MADAN

Keyword(s):

Refractive Index ◽

Wave Propagation ◽

Structure Constant ◽

Upper Atmosphere ◽

Index Structure ◽

Wind Profiler ◽

Scale Size ◽

Half Wavelength ◽

Measurement And Analysis ◽

Seasonal Basis

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