CASA: NSF Center for Collaborative Adaptive Sensing of the Atmosphere

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CASA NSF Center for Collaborative Adaptive
Sensing of the Atmosphere
Dr. José Colom-Ustáriz
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Global Warming and Weather

• One of the expected consequences of global
  warming is extreme weather events such as
• Hurricane intensity
• Number of Tornadoes
• We therefore NEED, better detection, monitoring,
  prediction and modeling is needed.

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There is insufficient knowledge about what is
actually happening (or is likely to happen) at
theEarths surface where people live. NRC 1998
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Observation Limitations
Single NEXRAD (TJUA) in PR Distance Cayey to
Mayagüez 100km Site Elevation 850 m Curvature
Beam Elevation (Above Site) 600 m Total Beam
Elevation (Above SL) 1.4 km
NEXRAD Rainfall 1 Hour Total
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This System underneath NEXRAD
Water spout at Mayaguez, PR- Sept 2005
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CASA dense networks of low power radars

• Year 5 of a 10 year program

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Whats needed to solve this problem?
Remote sensing Microwave engineering Networking Di
stributed systems Numerical prediction Emergency
management Radar meteorology Quantitative
inversion Climate studies Social impact Antenna
design
expertise
working together
core partners
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Were not going to do this alone!
Industrial, government, and academic outreach
partners
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Qué tenemos en Puerto Rico ?

• Dos Radares PR1 y PR2 (EWR)
• Proveen medidas de Reflectividad
• Radares son single-pol no son Doppler.
• Datos se ha colectado durante tormentas de lluvia.

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Puerto Rico IP3 Test Bed
Off-the-Grid Radar 1er nodo bajo prueba en UMass
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What is a Radar?Radio detection and ranging

• How does a radar work?
• Games

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(No Transcript)
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Compare to Acoustic Echo-location
hello
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Acoustic Echo-location
hello
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Acoustic Echo-location
hello
distance
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Hi !!
t 2 x range / speed of sound
Example range 150 m Speed of sound 340
meters/second t 2 X 150 / 340 1 second
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RADAR Echolocation(RADAR RAdio Detection And
Ranging)Microwave Echo-Location
Tx
Rx
Microwave Transmitter
Receiver
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Target Range
Tx
Rx
time
t 2 x range / speed of light measure t, then
determine Range
Example t .001 sec Speed of light c 3x108
meters/second Range .001 x 3x108 / 2
150,000 m 150 km
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• We will see that Radars work by
• Transmitting microwave pulses.
• and measuring the
• Time delay (range)
• Amplitude
• Frequency
• Polarization
• of the microwave echo in each range gate

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Target Radial Velocity
Frequency ft
Frequency ft fd
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Target Radial Velocity
Frequency ft
Frequency ft fd
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Zero Velocity for Crossing Targets
Frequency ft
Doppler Frequency
Frequency ft fd
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QPE Quantitative Precipitation Estimation
0.1 mm/hr
1 mm/hr
15 mm/hr
100 mm/hr
gt150 mm/hr
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Play the games to learn the basics

• http//whyfiles.org
• http//meted.ucar.edu/hurrican/strike/index.htm
• http//meted.ucar.edu/hurrican/strike/
• http//meted.ucar.edu/hurrican/strike/info_3.htm
• http//www.nws.noaa.gov/om/hurricane/index.shtml
• http//www.nws.noaa.gov/om/edures.htm

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More Games for Kids 4-104

• http//www.nws.noaa.gov/om/reachout/kidspage.shtml

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References

• The COMET project http//www.comet.ucar.edu/
• NASA TRMM
• NCAR (National Center for Atmospheric Research) -
  University Corporation for Atmospheric Research
  (UCAR)
• NOAA Educational Page http//www.nssl.noaa.gov/ed
  u/ideas/radar.html
• Dave McLaughlin Basics of Radars presentation
• NWS http//www.crh.noaa.gov/fsd/soo/doppler/doppl
  er.htm