**Section 3.2 OSIP Business Case Analysis for OSIP Project \# 04-002**

**WSR-88D Data Resolution and Coverage Enhancements**

**3.2.1 Executive Summary**

WSR-88D systems are operated by three agencies: Department of Commerce
(DOC), Department of Defense (DOD), and Department of Transportation
(DOT). Operations and Maintenance support is provided by the Radar
Operations Center (ROC) located in Norman, Oklahoma. NEXRAD Product
Improvement (NPI) activities are managed in the Office of Science and
Technology (OS&T), Program and Plans Division. Systems Engineering for
NPI is provided by OS&T Systems Engineering Center (SEC).

NOAA's NWS needs additional and improved radar data to improve support
to severe weather warnings, flood and flash flood warnings, and general
forecast services (reference NWS SON 04-004). Upon deployment of the
NEXRAD Open Radar Data Acquisition (RDA) the opportunity exists to
Number range CHAPTERgenerate much finer spatial resolution data and to
increase the range of Doppler data. The WSR-88D Super-Resolution Project
(Super Resolution) will provide data with a sample size of 0.25km by 0.5
degree, and will extend Doppler data to a range of 300 km. These data
improvements will provide for more detailed analysis of particular
storms and support improvements in NWS warnings and forecasts.

This modification is a set of software releases to the RDA, Radar
Product generator (RPG) and display systems. The Super Resolution
WSR-88D Proof-of-Concept activity was performed by the National Severe
Storms Laboratory (NSSL). Options for production software development on
the RDA include 1) additional tasking under the existing ORDA
development contract, 2) utilize ROC resources, 3) utilize resources
available in SEC, or 4) some combination of the above. The RPG
development will be performed by the ROC software engineering group, and
related product display modifications will be performed by the
associated software development groups (e.g., AWIPS software development
supports AWIPS-required software modifications). Software integration
and deployment of software releases for the RDA and RPG are performed by
the ROC.

**3.2.2 Project/Investment Description**

The spatial sampling of the current operational system (Legacy
Resolution) is 1km by 1° for Reflectivity, and 250m by 1° for Doppler.
Super-Resolution spatial sampling is 250m by 0.5° for both Reflectivity
and Doppler. The maximum range for Doppler data currently is 230km;
Super Resolution will increase this range to 300km. The increased
resolution provides more storm detail to the WSR-88D user. The expanded
Doppler range will provide more storm data in cases where an adjacent
WSR-88D may be out of operation, or is at a longer range from a given
storm. Together, these data improvements will increase the probability
that severe weather features will be identified and severe weather
warnings will be issued in a timely manner.

***Improved Angular and Range Resolution***

**Better Detail on Structure of Tornadoes**

![](media/image1.png){width="1.5833333333333333in"
height="1.5229166666666667in"}

**Current Reflectivity: 1.0**° **x 1.0 km Super-Resolution Reflectivity:
0.5**° **x 0.25 km**

Super Resolution will be implemented with software changes to the RDA,
RPG and display systems. The initial deployment will require that the
RPG recombine the Super-Resolution data to Legacy Resolution before it
is input to the current algorithms in order to meet error-of-estimates
requirements. New software has been prototyped by NSSL to produce
super-resolution base products for the user display systems. The display
systems require modification to incorporate these super-resolution
displays. Future development will evaluate the effectiveness of
utilizing Super Resolution data in algorithms such as Mesocyclone
Detection and Tornado Detection.

**3.2.3 Alternatives and Analysis**

Several alternative technical approaches were evaluated (see the summary
table in attachment 1). The accuracy with which the WSR-88D makes moment
estimates is directly dependent on the number of samples used by the
signal processor for a given radial. Recent, and planned, improvements
in range/velocity ambiguity mitigation and clutter filtering are also
dependent on a sufficient number of samples per radial. Recent work by
NCAR, validated by NSSL, has shown that an appropriate weighting of the
samples forming a 1° radial (termed windowing) can provide very good
accuracy while still achieving the desired increase in data resolution.
An operational constraint is that WSR-88D users need storm data to be
updated as frequently as possible for timely tornado warnings. Finally,
while Super Resolution base products will be generated, the WSR-88D
derived product algorithms (e.g., Mesocyclone Detection, Tornado
Detection, Precipitation Estimation) were developed with Legacy
Resolution data, and have not been tested with Super Resolution data.
These algorithms must initially, therefore, continue to be provided
Legacy Resolution data. The alternative approaches are described below,
beginning with the recommended approach.

1.  **Alternatives Description**

**a.** Use overlapping 1° radials, utilizing current VCP scanning rates.
Employ window weighting (von Hann window weighting where clutter
filtering is not needed, and Blackman window weighting where clutter
filtering is needed) to achieve Super Resolution data. Perform
recombination of Super Resolution data to Legacy Resolution in the RPG.

**b.** Use overlapping 1° radials with no windowing, utilizing current
VCP scanning rates. Since these radials include a subset that
corresponds exactly to the current RDA sampling, use this subset
directly to generate a Legacy Resolution buffer in the RPG.

**c.** Produce two data streams at the RDA, one with 0.5° azimuthal data
sampling, one with 1° azimuthal data sampling.

**d.** Perform 0.5° sampling using only those pulses falling within a
0.5° radial. Slow the scanning rate to provide a sufficient number of
pulses to meet moment estimation accuracy requirements. Perform
recombination of Super Resolution data to Legacy Resolution in the RPG
or produce a separate 1° data stream in the RDA.

**e.** Perform 0.5° sampling using only those pulses falling within a
0.5° radial, using current VCP scanning rates. Accept higher errors of
estimates. Perform recombination of Super Resolution data to Legacy
Resolution in the RPG or produce a separate 1° data stream in the RDA.

**f.** Perform 0.5° sampling using only those pulses falling within a
0.5° radial, using current VCP scanning rates. Perform range
oversampling with pseudowhitening to achieve current level of estimation
accuracy.

**3.2.3.2 Alternatives Analysis**

**Alternative a - 1° Sampling, overlapping radials, window weighting**

+-------------------------+--------------------------------------------+
| Benefits                | -   Improved tornado warnings              |
|                         |                                            |
|                         | -   Desired azimuthal and range resolution |
|                         |     improvement                            |
+-------------------------+--------------------------------------------+
| Science / Technical     | -   Tornado signatures detectable at 50%   |
| Merit                   |     greater range                          |
|                         |                                            |
|                         | -   Rotational Shear signatures 15%-20%    |
|                         |     stronger                               |
|                         |                                            |
|                         | -   Compatible with GMAP, SZ-2 and Dual    |
|                         |     Pol                                    |
|                         |                                            |
|                         | -   Increased standard deviation of moment |
|                         |     estimates:                             |
|                         |                                            |
|                         |     -   Z: 0.6 dB to 0.8 dB                |
|                         |                                            |
|                         |     -   V: 0.96 m/s to 1.35 m/s            |
+-------------------------+--------------------------------------------+
| Operational, System,    | -   Increased capacity requirements on     |
| and Business Impacts    |     RDA, RPG and comms infrastructure      |
|                         |                                            |
|                         | -   Added display products for display     |
|                         |     systems and partners                   |
+-------------------------+--------------------------------------------+
| Life cycle costs        | -   Development cost (\[sync up with       |
| (including development, |     Program Plan\]                         |
| acquisition, operations |                                            |
| and maintenance, and    | -   Non-recurring costs incurred by        |
| sustainability; include |     OST/SEC, OHD, ROC, NSSL, OST/PPD and   |
| all non-recurring and   |     WDTB                                   |
| recurring costs)        |                                            |
|                         | -   No added recurring costs               |
+-------------------------+--------------------------------------------+
| Schedule                | -   Build 10 (2QFY08)                      |
+-------------------------+--------------------------------------------+
| Risks                   | -   Added capacity requirements exceed     |
|                         |     RDA, RPG and comms infrastructure      |
|                         |     capability                             |
|                         |                                            |
|                         | -   Development not complete on time       |
+-------------------------+--------------------------------------------+
| Policy Compliance       | -   No 508/515 Impact                      |
+-------------------------+--------------------------------------------+
| Management              | -   Within NPI Purview                     |
+-------------------------+--------------------------------------------+
| Other                   | -                                          |
+-------------------------+--------------------------------------------+

**Alternative b - 1° Sampling, overlapping radials, no windowing**

+-------------------------+--------------------------------------------+
| Benefits                | -   Some improvement in tornado warnings   |
|                         |                                            |
|                         | -   Desired improvement in range           |
|                         |     resolution                             |
|                         |                                            |
|                         | -   Some improvement in azimuthal          |
|                         |     resolution                             |
+-------------------------+--------------------------------------------+
| Science / Technical     | -   Tornado signatures not improved as     |
| Merit                   |     much as Alternative a                  |
|                         |                                            |
|                         | -   No increase in estimation errors       |
|                         |     compared to legacy levels              |
+-------------------------+--------------------------------------------+
| Operational, System,    | -   Increased capacity requirements on     |
| and Business Impacts    |     RDA, RPG and comms infrastructure      |
|                         |                                            |
|                         | -   Added display products for display     |
|                         |     systems and partners                   |
+-------------------------+--------------------------------------------+
| Life cycle costs        | -   Development cost (\[sync up with       |
| (including development, |     Program Plan\]                         |
| acquisition, operations |                                            |
| and maintenance, and    | -   Non-recurring costs incurred by        |
| sustainability; include |     OST/SEC, OHD, ROC, NSSL, OST/PPD and   |
| all non-recurring and   |     WDTB                                   |
| recurring costs)        |                                            |
|                         | -   No added recurring costs               |
+-------------------------+--------------------------------------------+
| Schedule                | -   Build 10 (2QFY08)                      |
+-------------------------+--------------------------------------------+
| Risks                   | -   Added capacity requirements exceed     |
|                         |     RDA, RPG and comms infrastructure      |
|                         |     capability; RPG in particular is       |
|                         |     impacted                               |
|                         |                                            |
|                         | -   Development not complete on time       |
+-------------------------+--------------------------------------------+
| Policy Compliance       | -   No 508/515 Impact                      |
+-------------------------+--------------------------------------------+
| Management              | -   Within NPI Purview                     |
+-------------------------+--------------------------------------------+
| Other                   | -                                          |
+-------------------------+--------------------------------------------+

**Alternative c - 0**.5° Sampling/1° Sampling on two data streams

+-------------------------+--------------------------------------------+
| Benefits                | -   Provides desired azimuthal and range   |
|                         |     sampling                               |
|                         |                                            |
|                         | -   Improves tornado warnings              |
+-------------------------+--------------------------------------------+
| Science / Technical     | -   Tornado signatures detectable at 50%   |
| Merit                   |     greater range                          |
|                         |                                            |
|                         | -   Rotational shear signatures 15%-20%    |
|                         |     stronger                               |
|                         |                                            |
|                         | -   Produce legacy-equivalent data in      |
|                         |     parallel with super-res data           |
|                         |                                            |
|                         | -   Doubling of moment estimation errors   |
|                         |     for Super Resolution data              |
+-------------------------+--------------------------------------------+
| Operational, System,    | -   Increased capacity requirements on     |
| and Business Impacts    |     RDA, RPG and comms infrastructure      |
|                         |                                            |
|                         | -   Added display products for display     |
|                         |     systems and partners                   |
|                         |                                            |
|                         | -   Large increase in RDA processor load   |
|                         |     and RDA-RPG comms load                 |
+-------------------------+--------------------------------------------+
| Life cycle costs        | -   Development cost (\[sync up with       |
| (including development, |     Program Plan\]                         |
| acquisition, operations |                                            |
| and maintenance, and    | -   Non-recurring costs incurred by        |
| sustainability; include |     OST/SEC, OHD, ROC, NSSL, OST/PPD and   |
| all non-recurring and   |     WDTB                                   |
| recurring costs)        |                                            |
|                         | -   No added recurring costs               |
+-------------------------+--------------------------------------------+
| Schedule                | -   Build 10 (2QFY08)                      |
+-------------------------+--------------------------------------------+
| Risks                   | -   Added capacity requirements exceed     |
|                         |     RDA, RPG and comms infrastructure      |
|                         |     capability; RDA in particular is       |
|                         |     impacted                               |
|                         |                                            |
|                         | -   Development not complete on time, RDA  |
|                         |     development needed                     |
+-------------------------+--------------------------------------------+
| Policy Compliance       | -   No 508/515 Impact                      |
+-------------------------+--------------------------------------------+
| Management              | -   Within NPI Purview                     |
+-------------------------+--------------------------------------------+
| Other                   | -                                          |
+-------------------------+--------------------------------------------+

**Alternative d -- 0.5° sampling, s**low antenna rotation rate to
acquire adequate samples

+-------------------------+--------------------------------------------+
| Benefits                | -   Provides desired azimuthal and range   |
|                         |     sampling                               |
|                         |                                            |
|                         | -   Improves tornado warnings              |
+-------------------------+--------------------------------------------+
| Science / Technical     | -   Tornado signatures detectable at 50%   |
| Merit                   |     greater range                          |
|                         |                                            |
|                         | -   Rotational shear signatures 15%-20%    |
|                         |     stronger                               |
|                         |                                            |
|                         | -   No increase in moment estimation       |
|                         |     errors                                 |
|                         |                                            |
|                         | -   Slower VCPs                            |
+-------------------------+--------------------------------------------+
| Operational, System,    | -   Increased capacity requirements on     |
| and Business Impacts    |     RDA, RPG and comms infrastructure      |
|                         |                                            |
|                         | -   Added display products for display     |
|                         |     systems and partners                   |
|                         |                                            |
|                         | -   Slower VCPs during periods of severe   |
|                         |     weather are likely unacceptable to     |
|                         |     operations                             |
+-------------------------+--------------------------------------------+
| Life cycle costs        | -   Development cost (\[sync up with       |
| (including development, |     Program Plan\]                         |
| acquisition, operations |                                            |
| and maintenance, and    | -   Non-recurring costs incurred by        |
| sustainability; include |     OST/SEC, OHD, ROC, NSSL, OST/PPD and   |
| all non-recurring and   |     WDTB                                   |
| recurring costs)        |                                            |
|                         | -   No added recurring costs               |
+-------------------------+--------------------------------------------+
| Schedule                | -   Build 10 (2QFY08)                      |
+-------------------------+--------------------------------------------+
| Risks                   | -   Added capacity requirements exceed     |
|                         |     RDA, RPG and comms infrastructure      |
|                         |     capability; RPG in particular is       |
|                         |     impacted                               |
|                         |                                            |
|                         | -   Development not complete on time       |
|                         |                                            |
|                         | -   Unacceptable operational impact        |
|                         |     because of slower VCPs                 |
+-------------------------+--------------------------------------------+
| Policy Compliance       | -   No 508/515 Impact                      |
+-------------------------+--------------------------------------------+
| Management              | -   Within NPI Purview                     |
+-------------------------+--------------------------------------------+
| Other                   | -                                          |
+-------------------------+--------------------------------------------+

**Alternative e -- 0.5° Sampling, accept** higher errors of estimates

+-------------------------+--------------------------------------------+
| Benefits                | -   Provides desired azimuthal and range   |
|                         |     sampling                               |
|                         |                                            |
|                         | -   Improves tornado warnings              |
+-------------------------+--------------------------------------------+
| Science / Technical     | -   Tornado signatures detectable at 50%   |
| Merit                   |     greater range                          |
|                         |                                            |
|                         | -   Rotational shear signatures 15%-20%    |
|                         |     stronger                               |
|                         |                                            |
|                         | -   Doubling of moment estimation errors   |
+-------------------------+--------------------------------------------+
| Operational, System,    | -   Added display products for display     |
| and Business Impacts    |     systems and partners                   |
|                         |                                            |
|                         | -   Other products may be degraded due to  |
|                         |     additional errors in estimates         |
+-------------------------+--------------------------------------------+
| Life cycle costs        | -   Development cost (\[sync up with       |
| (including development, |     Program Plan\]                         |
| acquisition, operations |                                            |
| and maintenance, and    | -   Non-recurring costs incurred by        |
| sustainability; include |     OST/SEC, OHD, ROC, NSSL, OST/PPD and   |
| all non-recurring and   |     WDTB                                   |
| recurring costs)        |                                            |
|                         | -   No added recurring costs               |
+-------------------------+--------------------------------------------+
| Schedule                | -   Build 10 (2QFY08)                      |
+-------------------------+--------------------------------------------+
| Risks                   | -   Unacceptable level of errors in        |
|                         |     estimates, compromising usability of   |
|                         |     products                               |
+-------------------------+--------------------------------------------+
| Policy Compliance       | -   No 508/515 Impact                      |
+-------------------------+--------------------------------------------+
| Management              | -   Within NPI Purview                     |
+-------------------------+--------------------------------------------+
| Other                   | -                                          |
+-------------------------+--------------------------------------------+

**Alternative f - Super-resolution with oversampling and
pseudowhitening**

+-------------------------+--------------------------------------------+
| Benefits                | -   Provides desired azimuthal and range   |
|                         |     sampling                               |
|                         |                                            |
|                         | -   Improves tornado warnings              |
+-------------------------+--------------------------------------------+
| Science / Technical     | -   Tornado signatures detectable at 50%   |
| Merit                   |     greater range                          |
|                         |                                            |
|                         | -   Rotational shear signatures 15%-20%    |
|                         |     stronger                               |
|                         |                                            |
|                         | -   Minimize effect of errors in estimates |
|                         |                                            |
|                         | -   May not be compatible with SZ-2 and    |
|                         |     Dual Pol samples requirements          |
+-------------------------+--------------------------------------------+
| Operational, System,    | -   Added display products for display     |
| and Business Impacts    |     systems and partners                   |
|                         |                                            |
|                         | -   Additional processing capacity         |
|                         |     required                               |
+-------------------------+--------------------------------------------+
| Life cycle costs        | -   Development cost (\[sync up with       |
| (including development, |     Program Plan\]                         |
| acquisition, operations |                                            |
| and maintenance, and    | -   Non-recurring costs incurred by        |
| sustainability; include |     OST/SEC, OHD, ROC, NSSL, OST/PPD and   |
| all non-recurring and   |     WDTB                                   |
| recurring costs)        |                                            |
|                         | -   No added recurring costs               |
+-------------------------+--------------------------------------------+
| Schedule                | -   Build 13 (3QFY11)                      |
+-------------------------+--------------------------------------------+
| Risks                   | -   Increased processing capacity          |
|                         |     requirements                           |
|                         |                                            |
|                         | -   Increased testing requirements         |
|                         |                                            |
|                         | -   This Alternative cannot be developed   |
|                         |     in time to meet the Super Resolution   |
|                         |     schedule, and is no longer a viable    |
|                         |     alternative for Super Resolution       |
|                         |     Initial Operating Capability           |
+-------------------------+--------------------------------------------+
| Policy Compliance       | -   No 508/515 Impact                      |
+-------------------------+--------------------------------------------+
| Management              | -   Within NPI Purview                     |
+-------------------------+--------------------------------------------+
| Other                   | -                                          |
+-------------------------+--------------------------------------------+

**3.2.3.3 Solution Selection**

The various alternatives were presented to the NEXRAD Technical Advisory
Committee and to the NEXRAD Program Management Committee. Option "a" was
selected as the approach which would provide the desired functionality
in a timely manner with the least impact on system capacity and still
achieve errors-of-estimates requirements.

**3.2.4 Enterprise Architecture (EA)**

NEXRAD and associated system modifications are a service component for
several Lines of Business, including Disaster Management, Environmental
Management, Internal Risk Management and Mitigation and Recreational
Resource Management and Tourism. Reference the NOAA Enterprise
Architecture:
(<https://bestpractices.nws.noaa.gov/contents/ea/documentations/Section_6_Weather_&_Water_02032006.pdf>)

The proposed modification is consistent with the agency target
architecture. NEXRAD is a key Observing System. NPI is directly
consistent with planned outcomes of the target architecture. As stated
in Version 1.4 of the NOAA Enterprise Architecture document, \"In order
to migrate from the current to target architecture Weather and Water
must sustain on-going improvements and address remaining deficiencies in
all seven programs and sub-goals. To do so requires the Weather and
Water:

• Improve lead times for watches and warnings

• Improve accuracy for weather forecasts

• Improve integration and interoperability between program and sub-goals

• Improve prioritization of research and development

Regarding types of data used, this project uses major subject areas
identified in the NWS ITA Vol. IV:

-   Observation - radar data collected by NEXRAD

-   Reference data -geographic, operational, and management and support
    information

-   Science - hydrometerological knowledge required to develop and
    operate the forecast techniques required for the NWS mission.

This project will collect radar data in a manner allowing for enhanced
forecast and warning processes. NPI will implement the Super-resolution
capability to improve severe weather detection and warnings.

**3.2.5 Security and Privacy**

Security for NEXRAD Product Improvement (NPI) project is provided for
and funded by the three participating agencies through development costs
paid in accordance with the cost-share MOA. NPI will ensure conformance
to each agency's security requirements, building off the existing NEXRAD
security implementation. Security requirements will be tested as a part
of the System test Program. An increment to the Certification and
Accreditation package will be developed in accordance with Radar
Operation Center, the system owner. It is not expected that
super-resolution will materially impact any aspect of NEXRAD security
and privacy.

**3.2.6 Program/Project (Investment) Management**

The Project Manager has been qualified to run this Level 2 project.
Project Manager Information:

Gregory Cate (Project Manager Level Validation = 3).

Address: 2227 WEST LINDSEY NORMAN OK 73069

Phone: 405-366-9243 x3510

Email: Gregory.S.Cate@noaa.gov

The NEXRAD Product Improvement Program Manager reports to the Chief of
the Program Management Branch within the NWS Office of Science and
Technology.

## 3.2.7 Government Paperwork Elimination Act (GPEA)

## Not applicable. This system does not implement electronic transactions or record-keeping.