Seasonal results of aspect sensitivity from an MF radar over Kunming (25.6°N, 103.8°E), China

Abstract. The spring of 1997 has represented a stable period of operation for the joint University of Tromsø / University of Saskatchewan MF radar, being between refurbishment and upgrades. We examine the horizontal winds from the February to June inclusive and also include estimates of energy dissipation rates derived from signal fading times and presented as upper limits on the turbulent energy dissipation rate, ε. Here we address the periodicity in the dynamics of the upper mesosphere for time scales from hours to one month. Thus, we are able to examine the changes in the spectral signature of the mesospheric dynamics during the transition from winter to summer states.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; turbulence; waves and tides).

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Observation and Study of the Aspect Sensitivity and Echo Mechanism Based on the Wuhan MST Radar

IEEE Geoscience and Remote Sensing Letters ◽

10.1109/lgrs.2018.2871824 ◽

2019 ◽

Vol 16 (2) ◽

pp. 211-215

Author(s):

Haiyin Qing ◽

Zhengyu Zhao ◽

Yaohui Xu ◽

Chen Zhou

Keyword(s):

Mst Radar ◽

Aspect Sensitivity

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NLC and the background atmosphere above ALOMAR

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-5701-2011 ◽

2011 ◽

Vol 11 (12) ◽

pp. 5701-5717 ◽

Cited By ~ 41

Author(s):

J. Fiedler ◽

G. Baumgarten ◽

U. Berger ◽

P. Hoffmann ◽

N. Kaifler ◽

...

Keyword(s):

Diurnal Cycle ◽

Middle Atmosphere ◽

Thermal State ◽

Atmospheric Tides ◽

Data Set ◽

Ice Particles ◽

Cloud Water Content ◽

Radar Measurements ◽

Mf Radar

Abstract. Noctilucent clouds (NLC) have been measured by the Rayleigh/Mie/Raman-lidar at the ALOMAR research facility in Northern Norway (69° N, 16° E). From 1997 to 2010 NLC were detected during more than 1850 h on 440 different days. Colocated MF-radar measurements and calculations with the Leibniz-Institute Middle Atmosphere (LIMA-) model are used to characterize the background atmosphere. Temperatures as well as horizontal winds at 83 km altitude show distinct differences during NLC observations compared to when NLC are absent. The seasonally averaged temperature is lower and the winds are stronger westward when NLC are detected. The wind separation is a robust feature as it shows up in measurements as well as in model results and it is consistent with the current understanding that lower temperatures support the existence of ice particles. For the whole 14-year data set there is no statistically significant relation between NLC occurrence and solar Lyman-α radiation. On the other hand NLC occurrence and temperatures at 83 km show a significant anti-correlation, which suggests that the thermal state plays a major role for the existence of ice particles and dominates the pure Lyman-α influence on water vapor during certain years. We find the seasonal mean NLC altitudes to be correlated to both Lyman-α radiation and temperature. NLC above ALOMAR are strongly influenced by atmospheric tides. The cloud water content varies by a factor of 2.8 over the diurnal cycle. Diurnal and semidiurnal amplitudes and phases show some pronounced year-to-year variations. In general, amplitudes as well as phases vary in a different manner. Amplitudes change by a factor of more than 3 and phases vary by up to 7 h. Such variability could impact long-term NLC observations which do not cover the full diurnal cycle.

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MF radar interferometer measurements of meteor trail motions

Radio Science ◽

10.1029/rs025i004p00649 ◽

1990 ◽

Vol 25 (4) ◽

pp. 649-655 ◽

Cited By ~ 7

Author(s):

C. E. Meek ◽

A. H. Manson

Keyword(s):

Meteor Trail ◽

Mf Radar

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A comparison of northern hemisphere winds using SuperDARN meteor trail and MF radar wind measurements

Journal of Geophysical Research Atmospheres ◽

10.1029/2000jd900272 ◽

2000 ◽

Vol 105 (D14) ◽

pp. 18053-18066 ◽

Cited By ~ 17

Author(s):

G. C. Hussey ◽

C. E. Meek ◽

D. André ◽

A. H. Manson ◽

G. J. Sofko ◽

...

Keyword(s):

Northern Hemisphere ◽

Meteor Trail ◽

Wind Measurements ◽

Mf Radar

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Aspect sensitivity of VHF scatterers in the troposphere and stratosphere from comparisons of powers in off-vertical beams

Journal of Atmospheric and Terrestrial Physics ◽

10.1016/0021-9169(94)00056-t ◽

1995 ◽

Vol 57 (6) ◽

pp. 655-663 ◽

Cited By ~ 29

Author(s):

D. Hooper ◽

L. Thomas

Keyword(s):

Aspect Sensitivity

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Signatures of mesospheric particles in ionospheric data

Annales Geophysicae ◽

10.5194/angeo-27-823-2009 ◽

2009 ◽

Vol 27 (2) ◽

pp. 823-829 ◽

Cited By ~ 16

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.

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Mesospheric turbulent velocity estimation using the Buckland Park MF radar

Annales Geophysicae ◽

10.5194/angeo-19-1007-2001 ◽

2001 ◽

Vol 19 (8) ◽

pp. 1007-1017 ◽

Cited By ~ 21

Author(s):

D. A. Holdsworth ◽

R. A. Vincent ◽

I. M. Reid

Keyword(s):

Annual Variation ◽

Middle Atmosphere ◽

Velocity Estimation ◽

Turbulent Velocity ◽

Radio Science ◽

Meteorology And Atmospheric Dynamics ◽

Zonal Velocity ◽

Instruments And Techniques ◽

Full Correlation Analysis ◽

Mf Radar

Abstract. This paper investigates turbulent velocity estimation using the full correlation analysis (FCA) of spaced antenna (SA) data, and its application to the routine FCA observations of the Buckland Park MF (BPMF) radar. The effects of transmitter beamwidths are investigated, confirming the suggestions of previous authors that wide transmit beam widths lead to an overestimation of the turbulent velocity. The annual variation of the turbulent velocity is investigated, revealing an increase in turbulent velocity with height, and equinoctal minima and solstice maxima observed below 80 km. Investigations of the turbulent velocities about the March diurnal tide maximum reveals a diurnal variation in phase with the zonal velocity. Harmonic analysis reveals this relationship exists between February and September. Descending power layers are also observed during this period. A number of mechanisms are proposed to describe these observations.Key words. Meteorology and atmospheric dynamics (middle atmosphere dynamics; instruments and techniques) – Radio science (instruments and techniques)

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