Phased Array R&D at NSSL

Phased Array Weather Radar Project Joint Action GroupDecember 7, 2004

Topic Outline

1. Impact of NEXRAD2. PAR Status3. NOAA’s Partners4. Congressional Study5. Early Tests6. Vision7. Summary

Source: NWS Office of Science and Technology

NEXRAD

NEXRAD

NEXRAD Impact on Performance Measures

NEXRAD Impact on Society

• NEXRAD deployment reduced expected tornado fatalities by 45%.

• NEXRAD deployment reduced expected tornado injuries by 40%.

• Using EPA methods, this translates to a $378M benefit per year (8 years, FY03 dollars, deaths avoided only).

(Sutter and Simmons, 2005)

PAR Status• Navy accepts PAR from Lockheed Martin (Oct. 2003).• NSSL assigned to keep PAR “in good working order” as

per NOAA/FAA/Navy MOU (Oct. 2003).• Test and evaluation period underway (Oct. 2003 –

present).• NOAA funding for PAR ($1M, FY04; $2M, FY05).• Working problems with digital signal processor, cooling

system, and software (2004).• PAR now ready to collect data and perform

intercomparison and multi purpose use studies (January 2005 on).

• NOAA/FAA/NAVY calls for making PAR available to other agencies and research community by Dec. 2006.

NOAA’s Partners in PAR

• Navy – own SPY-1 antenna• FAA – investigating multi purpose use• U of Okla. – own environmental processor• CASA – UMASS, OU, CSU, U. of Puerto Rico• National Weather Service (NOAA NWS)• Lockheed Martin, BCI

Interpretation of the Aerospace Inc. Study

• The Aerospace Inc. study indicates that phased array transmit/receive (T/R) elements will enjoy significant cost reductions over present prices.

• Companies interviewed in the Aerospace study pegged 2010 costs for active, T/R elements to be in the $35-250 range.

• The SPY-1 antenna, containing ~ 5,000 individual passive elements at $1,500-2,000 each, cost ~$10M.

• Thus it will be possible to manufacture a phased array antenna for weather surveillance for less than $1M. Note that this antenna includes the transmitter and primary receiver (active T/R elements).

Early Tests - Reflectivity

PAR 20040530 012309Z 0.75deg KTLX 20040530 012310Z 0.5deg

Early Tests - Velocity (aliased)

PAR 20040530 012309Z 0.75deg KTLX 20040530 012327Z 0.5deg

Vision

• From Aerospace, Inc. Study• Multi Purpose Radar• Integrated Radar Network including CASA

radars• Using Radar Data to Initialize Forecast

Models

Vision from Aerospace, Inc. Study

Given this price breakthrough, it is now possible to envision a four-faced radar system (four antennae mounted as in a pyramid) that would yield a weather radar with no moving parts. This would greatly reduce lifecycle cost and yield a volume scanning rate of approximately 20 seconds. The current NEXRAD volume scanning rates are between 5 and 6 minutes.

Multi Purpose Vision

Integrated Radar Network Vision

Big (NOAA, FAA), little (CASA) radars, other (HLS, DOT,?) radars, built real-time accessible

data bases.

• Deployment of scalable radar systems

•Local, regional, national accessible databases

•Heavy involvement of state and local governments

•Potential commercial involvement

•Media involvement

Using Radar Data to Initialize Forecast Models

• Radar is the only technology that “measures” the atmosphere on the space and time scales of the phenomena one wants to forecast.

• Assimilation of radar data can retrieve wind, temperature, and “pressure” observations.

Using Radar Data to Initialize Forecast Models (2)

Using Radar Data to Initialize Forecast Models (3)

• Run very short term, very high resolution, ensemble based forecast models to get probabilistic forecasts of severe weather events.

• Move from “warn on detection” to “warn on forecast”.

• Extend tornado lead times from 12 minutes to 45 minutes.

Using Radar Data to Initialize Forecast Models (4)

• WFUS54 KOUN 032330• TOROKC• OKC151-040000-

• BULLETIN - EAS ACTIVATION REQUESTED• TORNADO WARNING• NATIONAL WEATHER SERVICE NORMAN OK• 630 PM CDT THU OCT 3 2002

• THE NATIONAL WEATHER SERVICE IN NORMAN HAS ISSUED A

• * TORNADO WARNING FOR...• WOODS COUNTY IN NORTHWEST OKLAHOMA

• * UNTIL 700 PM CDT

• * AT 630 PM CDT...DOPPLER RADAR DETECTED A SEVERE THUNDERSTORM • CAPABLE OF PRODUCING A TORNADO 13 MILES WEST OF CAPRON...MOVING • EAST-NORTHEAST AT 30 MPH.

• * LOCATIONS IN THE WARNING INCLUDE CAPRON

• IN ADDITION TO THE TORNADO THREAT... A LINE OF SEVERE THUNDERSTORMS • EXTENDS FROM THE KANSAS STATE LINE NORTHWEST OF ALVA TO 9 MILES WEST • OF AVARD. THESE THUNDERSTORMS WILL BE CAPABLE OF PRODUCING DAMAGING • WINDS AND HAIL TO THE SIZE OF HALF DOLLARS IN THE AVARD...CORA... • AVARD...HOPETON AND ALVA AREAS.

• TAKE COVER NOW. LEAVE MOBILE HOMES AND VEHICLES. IF POSSIBLE...MOVE• TO A BASEMENT OR STORM SHELTER. OTHERWISE MOVE TO AN INTERIOR ROOM OR• HALLWAY ON THE LOWEST FLOOR. STAY AWAY FROM WINDOWS AND OUTSIDE• WALLS.

• LAT...LON 3698 9895 3682 9884 3688 9854 3700 9854

• ...SPEG.

Summary• PAR technology will become cheap.• Multi-purpose radars are feasible:

– Weather surveillance– Radar data assimilation into very high resolution, very short

term, ensemble based forecast models– Aircraft tracking– Non-cooperative aircraft tracking– 4D measurements for dispersion winds– Chem/bio detection

• Polarization diversity, multi-frequency, active PAR T/R elements already exist.

• Can government agencies collaborate on a multi-purpose project of this magnitude?

Back Up

Slides

PAR Congressionally Mandated Study

• The October 2003 version of the Omnibus Appropriations Bill specifies, "A parallel assessment of the practicality of commercializing the SPY-1 or successor for weather forecasting is funded under the National Weather Service……NWS shall submit a feasibility study to the Committees on Appropriations no later than May 1 2004."

• The Aerospace Corporation produced an 89-page document as a result of a two-month, quick-look study effort that addresses these Congressional concerns.

Results of the Aerospace Inc. Study• “One company stated that the cost of PAR transmit/receive elements will go from

$1,200 in 1999 to $250 in 2010; another company informally estimated the 2010 cost at $100. The Aerospace Corporation thinks that the cost will be closer to $35, but this estimate needs additional substantiation.

• Market evidence and engineering statistics indicate significant increases to component reliability, which will greatly reduce the impact of single-point-of failure components and result in much lower recurring costs.

• Integration of PAR technology into the existing NEXRAD system could be done gracefully.

• A formal, in-depth analysis is required to provide a clear picture of the cost/benefits of Phased Array Radar for weather Doppler radar application.

• A more comprehensive, top-down study should be undertaken to define architectural requirements and performance objectives that can be addressed by PAR in the 2005-2020 timeframe.

• This comprehensive study needs to be done in concert with the NSSL to quantitatively identify the performance benefits of PAR in terms of severe weather detection and potential savings in life and property.”