scholarly journals Initial Results of Meteor Wind with Langfang Medium Frequency Radar

Atmosphere ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 507
Author(s):  
Bing Cai ◽  
Qingchen Xu ◽  
Xiong Hu ◽  
Junfeng Yang
Keyword(s):  
Pulse Frequency ◽  
Meteor Shower ◽  
Height Distribution ◽  
Meteor Radar ◽  
Medium Frequency ◽  
Very High Frequency ◽  
Sampling Pulse ◽  
Wind Profiles ◽  
Observation Period ◽  
Mf Radar

We conducted meteor observations during the Leonid meteor shower on 16 November 2017 and 17 November 2018 with Langfang medium frequency (MF) radar (116° E, 40° N). This was the first nighttime meteor observation by MF radar in mid-latitude China. The observation period was 12:00–22:00 (UT) and the observation range was 78–150 km. By using broad vertical beams, totally 94 and 92 meteor echoes were obtained, along with their spatial, time and height distribution. Quite a few meteor echoes are within 30° zenith angles, from the southwest direction, and with a mean height of 107 km which is almost 10 km higher than traditional VHF (Very High Frequency) meteor radar observations. Initial bi-hourly and nightly averaged wind profiles were calculated, and well fitted the wind estimations by co-located VHF meteor radar at the altitude of 100–110 km. On the other side, echoes around 140 km are successfully detected in our observation, which may suggest that for most running MF radars, meteor echoes around 140 km altitude could be detected with a sampling pulse frequency less than 100 Hz.

scholarly journals Signatures of mesospheric particles in ionospheric data

2009 ◽  
Vol 27 (2) ◽  
pp. 823-829 ◽  
Author(s):  
M. Friedrich ◽  
K. M. Torkar ◽  
W. Singer ◽  
I. Strelnikova ◽  
M. Rapp ◽  
...  
Keyword(s):  
Electron Density ◽  
Indirect Evidence ◽  
Meteor Radar ◽  
Sounding Rockets ◽  
Close Vicinity ◽  
Incoherent Scatter ◽  
Summer Echoes ◽  
In Situ Observations ◽  
Mf Radar

Abstract. The state of the ionosphere during the 2007 ECOMA/MASS campaign is described by in-situ observations by three sounding rockets launched from the Andøya Rocket Range and by ground based observations. The ground based measurements included the incoherent scatter radar EISCAT near Tromsø (both on UHF and VHF), as well as an MF radar, a meteor radar and an imaging riometer all located in the close vicinity of the rocket range. The pronounced electron density bite-outs seen by two of the rockets could not be detected from the ground, but the associated PMSE (Polar Mesospheric Summer Echoes) provide indirect evidence of pronounced perturbations of mesospheric electron densities.

A comparison of winds measured by meteor radar systems and an MF radar at Buckland Park

Radio Science ◽  
1997 ◽  
Vol 32 (2) ◽  
pp. 867-874 ◽  
Author(s):  
T. A. Valentic ◽  
J. P. Avery ◽  
S. K. Avery ◽  
R. A. Vincent
Keyword(s):  
Meteor Radar ◽  
Radar Systems ◽  
Mf Radar

scholarly journals Meteor shower velocity estimates from single-station meteor radar: accuracy and precision

2012 ◽  
Vol 425 (2) ◽  
pp. 1473-1478 ◽  
Author(s):  
J. P. Younger ◽  
I. M. Reid ◽  
R. A. Vincent ◽  
D. J. Murphy
Keyword(s):  
Meteor Shower ◽  
Meteor Radar ◽  
Accuracy And Precision ◽  
Single Station

Observations of the 2001 Leonid meteor shower using VHF meteor radar

Icarus ◽  
2008 ◽  
Vol 196 (1) ◽  
pp. 164-170 ◽  
Author(s):  
S DELAPENA ◽  
S AVERY ◽  
J AVERY
Keyword(s):  
Meteor Shower ◽  
Meteor Radar ◽  
Leonid Meteor Shower

Climatologies of mean winds and tides observed by medium frequency radars at Tromsø (70°N) and Saskatoon (52°N) during 1987–1989

1991 ◽  
Vol 69 (8-9) ◽  
pp. 966-975 ◽  
Author(s):  
A. H. Manson ◽  
C. E. Meek
Keyword(s):  
Real Time ◽  
Theoretical Models ◽  
Temperature Gradients ◽  
Medium Frequency ◽  
Partial Reflection ◽  
Modal Composition ◽  
The Mean ◽  
Data Yield ◽  
Partial Reflection Radar ◽  
Mf Radar

A real-time winds system from Saskatoon has operated with the Tromsø medium frequency (MF) (partial reflection) radar (70°N, 20°E) since mid-1987. Although the system has a poorer data yield than usual, owing to smaller receiving antennas, it has proven possible over 2 years to obtain 12 month climatologies of mean winds and tides (70–75 to 100 km) with a 10 d resolution. These are compared with similar products from the Saskatoon MF radar (52°N, 107°W). The mean winds and tides generally show similar seasonal morphologies. However the mean winds are weaker, consistent with smaller meridional temperature gradients. Also, there are significant changes in the tidal wavelengths and amplitudes suggesting that considerable adjustments of modal composition have occurred. The tides are compared with recent numerical-theoretical models.

scholarly journals Diurnal variation of short-period (20–120 min) gravity waves in the equatorial Mesosphere and Lower Thermosphere and its relation to deep tropical convection

2011 ◽  
Vol 29 (4) ◽  
pp. 623-629 ◽  
Author(s):  
N. Venkateswara Rao ◽  
Y. Shibagaki ◽  
T. Tsuda
Keyword(s):  
Gravity Wave ◽  
Gravity Waves ◽  
Theoretical Calculations ◽  
Lower Thermosphere ◽  
Tropical Convection ◽  
Peak Activity ◽  
Medium Frequency ◽  
Short Period ◽  
Mesosphere And Lower Thermosphere ◽  
Mf Radar

Abstract. We study short period gravity waves (20–120 min) in the equatorial Mesosphere and Lower Thermosphere (MLT) using a Medium Frequency (MF) radar at Pameungpeuk (7.4° S, 107.4° E), Indonesia. In particular, we study local time and seasonal variation of the gravity wave variance and its relation to tropical convection. The gravity wave variance at 88 km enhances between 20:00 LT and 07:00 LT, with a peak at 02:00–03:00 LT. The enhancement is mainly observed during February–April and September–October and shows inter-annual variability. Convective activity over the same location persists from 16:00–21:00 LT with a peak activity ~18:00 LT and enhances between November–April. Time delay between the peak of convection and that of gravity wave activity ranges 1–15 h, which is consistent with theoretical calculations and previous reports based on reverse ray tracing analysis.

scholarly journals Mesospheric gravity wave momentum flux estimation using hybrid Doppler interferometry

2017 ◽  
Vol 35 (3) ◽  
pp. 733-750 ◽  
Author(s):  
Andrew J. Spargo ◽  
Iain M. Reid ◽  
Andrew D. MacKinnon ◽  
David A. Holdsworth
Keyword(s):  
Gravity Wave ◽  
Reynolds Stress ◽  
Momentum Flux ◽  
Meteor Radar ◽  
Stress Components ◽  
Vertical Beam ◽  
Flux Estimation ◽  
Radar Resolution ◽  
Using Data ◽  
Mf Radar

Abstract. Mesospheric gravity wave (GW) momentum flux estimates using data from multibeam Buckland Park MF radar (34.6° S, 138.5° E) experiments (conducted from July 1997 to June 1998) are presented. On transmission, five Doppler beams were symmetrically steered about the zenith (one zenith beam and four off-zenith beams in the cardinal directions). The received beams were analysed with hybrid Doppler interferometry (HDI) (Holdsworth and Reid, 1998), principally to determine the radial velocities of the effective scattering centres illuminated by the radar. The methodology of Thorsen et al. (1997), later re-introduced by Hocking (2005) and since extensively applied to meteor radar returns, was used to estimate components of Reynolds stress due to propagating GWs and/or turbulence in the radar resolution volume. Physically reasonable momentum flux estimates are derived from the Reynolds stress components, which are also verified using a simple radar model incorporating GW-induced wind perturbations. On the basis of these results, we recommend the intercomparison of momentum flux estimates between co-located meteor radars and vertical-beam interferometric MF radars. It is envisaged that such intercomparisons will assist with the clarification of recent concerns (e.g. Vincent et al., 2010) of the accuracy of the meteor radar technique.

scholarly journals Meteor echo height ceiling effect and mesospheric temperature estimation from meteor radar observations

2018 ◽  
Vol 36 (5) ◽  
pp. 1267-1274 ◽  
Author(s):  
Changsup Lee ◽  
Geonhwa Jee ◽  
Jeong-Han Kim ◽  
In-Sun Song
Keyword(s):  
Mean Free Path ◽  
Peak Height ◽  
Ceiling Effect ◽  
Asymmetric Distribution ◽  
Height Distribution ◽  
Meteor Radar ◽  
Temperature Estimation ◽  
Radar Observations ◽  
Broadband Emission ◽  
Mesospheric Temperature

Abstract. The mesospheric temperature estimation from meteor height distribution is reevaluated by using the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) and the King Sejong Station (KSS) meteor radar observations. It is found that the experimentally determined proportionality constant between the full width at half maximum (FWHM) of the meteor height distribution and temperature is in remarkable agreement with theoretical value derived from the physics-based equation and it is nearly time-invariant for the entire observation period of 2012–2016. Furthermore, for the first time we found that the FWHM provides the best estimate of temperature at slightly lower height than the meteor peak height (MPH) by about 2–3 km. This is related to the asymmetric distribution of meteor echoes around MPH, which is known to be caused by the meteor echo height ceiling effect (MHC). At higher altitude above MPH, the meteor detection rate is greatly reduced due to the MHC, and the cutoff height for this reduction follows a fixed molecular mean free path of the background atmosphere. This result indicates that the meteor height distribution can be used to estimate the mesospheric temperature, even under the asymmetric meteor echo distribution caused by the MHC at high altitude.

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