SuperDARN: Meteor
Winds and Meteor
Processing
CEDAR Workshop, 2007
R. T. Parris, G. R. Bryson, W. A. Bristow
Geophysical Institute, University of Alaska Fairbanks
A. S. Yukimatu and M. Tsutsumi
National Institute of Polar Research
M. Freeman and M. Pinnock
British Antarctic Survey
Photo by W. A. Bristow
What the Radars
Observe
Meteors and SuperDARN
•
[Hall, et.al., 1997]
•
[Dai Wei, 2000]
Meteors and SuperDARN
•
Radars are well positioned for high latitude MLT studies
Three Techniques of Extracting
Meteor Region Information
• Extracting meteor data from the existing data
sets (British Antarctic Survey method)
– Hall, et.al., 1997
– Hibbins and Jarvis, 2007
– Hussey, et.al., 2000
• Using the existing hardware with new data
extraction and processing techniques to detect
meteor echoes (Time Series Method)
– Yukimatu and Tsutsumi, 2002
• Adapting the hardware and processing to better
detect meteor echoes (Digital Receiver Method)
British Antarctic Survey Method
[Hibbins and Jarvis, 2007, Hussey, et.al., 2000]
• Use selection criteria to classify meteor echoes in
existing data
–
–
–
–
–
Range <= 360 km
SNR > 3 dB
LOS velocity < 100 m/s
Velocity error < 50 m/s
Spectral width < 25 m/s
• Group meteors by beam and average to get hourly LOS
wind velocities
• Assume horizontal winds and assume winds constant
over field-of-view
• Use different beam directions to get vector winds
British Antarctic Survey Method
[Hibbins and Jarvis, 2007, Hussey, et.al., 2000]
[from Hibbins and Jarvis, 2007]
British Antarctic Survey Method
[Hibbins and Jarvis, 2007, Hussey, et.al., 2000]
Benefits
• This method can be
applied to all existing
data for all
SuperDARN radars
Caveats
• Range resolution is
nominally 45 km
• No altitude
information
Time Series Method
(Yukimatu and Tsutsumi, 2002)
Time Series Method
(Yukimatu and Tsutsumi, 2002)
Time Series Method
(Yukimatu and Tsutsumi, 2002)
Time Series Method
(Yukimatu and Tsutsumi, 2002)
Benefits
Caveats
• This method can be
• Range resolution is
run on all SuperDARN
nominally 15 km
radars
• No measured altitude
information – altitude
is inferred from
diffusion
Digital Receiver Method
στ1
⎛
⎞
1
⎟
≈ ⎜⎜
2
⎟
f
S
N
4
/
⎝ B
⎠
1/ 2
• Over-sample and
search for the rising
edge of echo
Meteor Trail
us
Si
gn
al
30
0
sm
it P
0
us ul
se
R
Ec
ho
30
Tr
an
• Use digital receiver
with flexible filtering
• Open the filter
bandwidth
Specular
Reflection
Radar
Station
Ground
s(t)+n(t)rms
Δt
s(t)
n(t)
Threshold
tR=1/fB
Digital Receiver Method
Power (decimal counts)
Ionospheric Scatter
TX Pulse
Meteor Echoes
Range (4.5 km range gates)
Digital Receiver Method
Hourly Wind Profiles
Digital Receiver Method
Benefits
Caveats
• High range resolution
• Only method that
measures altitude of
echoes
• Most like a typical
meteor radar
• Can only be run on
radars with digital
receivers
Meteor Data Acquisition
British Antarctic Survey
Data Access and Browsing System
• Northern Hemisphere Radars
–
–
–
–
–
–
–
Finland
Iceland-East
Goose Bay
Kapukasing
Saskatoon
Prince George
Kodiak
• Southern Hemisphere Radars
–
–
–
–
–
Syowa East
Syowa South
Sanae
Halley
Tiger
British Antarctic Survey
Data Access and Browsing System
• http://dabs.nerc-bas.ac.uk/dabs/
• Hourly averaged line-of-sight velocities
• Zonal and meridional wind components
– Number of points in average
– Standard deviation
– Latitude and longitude
Time Series Method
• Operating on SENSU Syowa radar since
2002
• Soon be running on ALL radars
• No publicly accessible data archive
– Contact Sessai Yukimatu
[email protected]
Digital Receiver Method
• Successful operation on Kodiak radar from
April 2003 – September 2006
• Update meteor software for new radar
operating system
• Distribute meteor software to Northern
Hemisphere SuperDARN radars for
implementation
• Construct Real-Time Data Access
–
–
–
–
ACF and XCF plots
Event, range, and altitude histograms
Decay times
Wind profiles
Acknowledgments
• British Antarctic Survey
– Mervyn Freeman
– Mike Pinnock
• National Institute of Polar Research
– Sessai Yukimatu
– Masaki Tsutsumi
References
•
•
•
•
•
Dai, Wei. Meteor Wind Wave Analysis of SuperDARN Observations.
Masters Thesis. University of Alaska Fairbanks. August 2000.
Hall, G. E., J. W. MacDougall, D. R. Moorcroft, J.-P. St.-Maurice, A. H.
Manson, and C. E. Meek. Super Dual Auroral Radar Network
observations of meteor echoes. Journal of Geophysical Research, Vol
102, No. A7. pp 14603-14614. July 1, 1997.
Hibbins, R. E., and M. J. Jarvis. A comparison of wind and tide
measurments in the upper mesosphere recorded with an imaging
Dopple interferometer and SuperDARN radar at Halley, Antarctica.
Atmospheric Chemistry and Physics Discussions. 7, 6573-6601, 2007.
Hussey, G. C., C. E. Meek, D. Andre, A. H. Manson, G J. Sofko and C. M.
Hall, A comparison of Northern Hemisphere winds using SuperDARN
meteor trail and MF radar wind measurements, Journal of Geophysical
Research, 105, D14, 18053-18066, 2000.
Yukimatu, Sessai Akira, Tsutsumi Masaki. A new SuperDARN raw time
series analysis method and its application to mesopause region
dynamics. Geophysical Research Letters. Submitted 2002.