Peter Taylor1 and Wayne Hocking2

1
The O-Q Net Windprofiler Project
Peter Taylor1 and Wayne Hocking2
1.York University, 2. University of Western
Ontario
MSC 7th Operational Meteorology Workshop
Walsingham
McDonald Campus, McGill
2
About Windprofilers
Radar windprofilers are instruments which measure
wind speeds and other related parameters within
the atmosphere over a relatively deep region.
Depending on the frequency and power used, this
height region could cover typically 400 meters
altitude to 10 or 15 km altitude, and even as
high as 25km for the most powerful
radars. Radar and windprofiler
primers http//quark.physics.uwo.ca/whocking/p10
3/radar.html http//quark.physics.uwo.ca/whocking
/cfi/home.html
3
VHF vs UHF/Microwave

• Very High Frequency (VHF) - 30 to 300 MHz
  (wavelengths of 10 metres to 1 metre)
• O-Q Wind Profilers signals from temperature
  and humidity fluctuations (turbulence) operate in
  the range 40-55 MHz.
• (McGill 52.00 MHz, Walsingham 44.5 MHz)
• Ultra High Frequency (UHF) - 300 to 3000 MHz
  (wavelengths of 1 metre to 10 centimetres)
• Microwave 1-300 GHz (30 cm to 1 mm)
• C-band - 4-8 GHz (wavelengths 7.5 to 3.75 cm)
  King Radar
• X-band - 8 -12 GHz (wavelengths 2.5 to 3.75 cm)
  ELBOW
• Weather Radar - signals from hydrometeors, and
  insects

4
They are useful in a wide variety of applications
for Windprofilers in meteorology. Examples
1. Numerical forecast models - upper level winds
help define the motions and persistence of lower
level systems
2. Early warning of catastrophic weather e.g.
Tornadic outbreak of May 3, 1999) (see
http//www.nws.noaa.gov/om/disaster/OK-KS/report7.
pdf)
3. Firefighting - identification of low level
wind jets
4. Measurement of turbulence strengths
and tropopause monitoring, studies of gravity
wave generation, pollution transport studies and
aviation meteorology.
5
With regard to Aviation meteorology
1. The radars cover the height regions in which
aircraft fly.
2. They are capable of producing real-time data
(nowcasting).
3. They can measure turbulence strengths as well
as wind speeds.
Also Better flight planning, permitting fuel
savings. Avoidance of severe turbulence and wind
shear.
AMDAR (Aircraft Meteorological Data Reporting)
Meteorological data can be obtained from large
areas of the World by collection of data from
aircraft fitted with appropriate software
packages. ASDAR (Aircraft to Satellite Data
Relay) ACARS (Aircraft Communication Addressing
and Reporting System)
6
Windprofilers offer the capability to complement
AMDAR and fill in its weaknesses.
MAPS
Each technique (AMDAR, Profilers)has strengths,
and by combining them, the sum of the whole will
exceed the sum of the parts.
So we conclude that Windprofilers have a
potentially very important role to play in all
sorts of areas of meteorology, including aviation
meteorology.
7
Windprofilers in the US. The USA has operated a
large NPN network of these profilers for the past
decade. Most of those radars operate at a
frequency of about 404 MHz. (UHF).
8
Cooperative Agency Profilers (CAP) The current
status of CAP sites in the continental US are
shown on the map below. Stars represent sites
that produce both wind and RASS data. Circles
represent sites that only produce wind data. The
majority of CAP systems are 915 MHz (UHF)
Boundary Layer Profilers, there are also several
449 MHz (UHF) and 50 MHz (VHF) profilers in the
CAP network.
Typical 915 MHz (UHF) Boundary Layer Profiler
with RASS(Photo Courtesy of Argonne National
Laboratory)
9
NPN/CAP Data Displays Feb 2006

• Note blue dot at EGBERT and red dots at McGill
  and Lunenberg
• http//www.profiler.noaa.gov/npn/profiler.jsp

10
Cape Canaveral Winds
11
Historically, Windprofilers began with
ionospheric radars working at 50 MHz. In
particular, the Jicamarca radar.
A long history of studies of the atmosphere with
VHF windprofilers then ensued, although at the
time they were called MST radars. Key groups
were the SOUSY group, NOAA, Jicamarca, Arecibo.
Others followed. Different VHF designs were
developed.
12
For Windprofiler applications, there are still
many advantages to VHF operation. These
include - Far less sensitive to precipitation
and clouds - Less sensitive to birds and
insects - Simpler electronics and less expensive
13

• But there are VHF disadvantages
• - Larger arrays needed (physical size is bigger)
• - Cannot get below 1.5 km altitude ---or can
  they??
• - Frequency allocation can be an issue (it is).
• Higher powers (50-100 kW).

In 1993, a VHF Windprofiler radar was built near
the University of Western Ontario. -low power -
only 10 kW peak. 10 duty cycle. In 1997,
another was installed at Resolute Bay (primarily
for mesospheric work) - again, low power (12 kW
peak).
14
Validation Radiosondes (Clovar)
15
Validation CMC analysis Note CMC analysed wind
speeds are 10-20 lower (on average) than
windprofiler data.
16
The O-Q Net Ontario and Quebecs version of a
windprofiler network. Built from WindTtracker
radars, operating at 40-55 MHz.
17
The New windprofiler network

• Connected to the web
• Data will be frequently updated (hourly)
• Data will be integrated into Numerical Forecast
  Models
• Radars will be used for aircraft flight planning
  and safety, and fuel economies.
• Radars will be employed in forecasts for
  firefighting
• Radars will be used to help anticipate severe
  weather
• Precipitation diagnostic to be further
  investigated
• Studies of fundamental science - waves,
  turbulence, mean flows, frontal systems etc.

18
WindTtrackers The upper levels winds (above
900m) are largely via Doppler. The beam angle is
10.9 degrees, in order to place a null vertically
and reduce specular contamination. For winds at
lower heights (lt 1.2 km), we use the loop
antennas. They use both Spaced Antenna and
Imaging Doppler Interferometry techniques. The
IDI is working best, but needs more testing.
Some useful web sites http//quark.physics.uwo.ca
/whocking/cfi/home.html http//www.radar.mcgill.c
a/vhf/ http//quark.physics.uwo.ca/whocking http
//www.yorku.ca/pat/O-QNet/Walsingham/
19
The Walsingham WindTtracker radar
x
20
(No Transcript)
21
Loop Antennas in background
Main Antennas
22
Receiving and Digitization System
23
Upper level winds early data
24
Walsingham, 2000 UTC, 25 Feb 06
25
Sample Numerical WindProfiler Data Walsingham
00Z, 25 Feb 2006 on, actual data extends to 12.5
km
26
Boundary-Layer Winds
27
Turbulence Measurements
28
An interesting recent Vortex from the McGill
Profiler
29
How can windprofiler data be used?

• What are most useful plots/pictures or numbers?
• Input to analyses or stand-alone information?
• Single profiler or network?
• Just winds or do we need T and q?
• Will forecasters have time to look at and
  interpret data?
• How can we help?
• 
  pat_at_yorku.ca
• http//www.yorku.ca/pat/O-QNet/Walsingham/

30
Acknowledgements

• Co-Is Isztar Zawadzki, Frederic Fabry, Gordon
  McBean, Bob Sica, Horia Hangan, Gary Klaassen,
  John Barron, Bob Mercer
• Canada Foundation for Innovation and Ontario
  Innovation Trust (for funding!)
• Mardoc for patience and in-kind contributions
• MSC for support and encouragement and site
  access (tba) (CARE, Trenton).
• Landowners Walsingham, Mary and Peter Gartshore
  Harrow, Agriculture and Agri-Food Canada (tba)
• York and Western Offices of Research Services.
  For interim financing (!) and management support.