1. NEXRAD Data and Products at NCDC
National Climatic Data Center
Brian Nelson
John Bates
Steve Ansari
Stephen Del Greco
NOAA/NESDIS

2. Outline Brief Overview of NEXRAD Data at NCDC Products at NCDC
Applications (software)
Product development
GEWEX connection
Working Group on Precipitation Radar Networks
Outline

3. NEXRAD Overview Weather Surveillance Radar – 1988 Doppler
Next Generation Radar
Development started in 1960s
Deployment started in 1988
First WSR-88D Site in 1990 Norman Ok
Last Site in 1997 in Indiana
Most Sites have been operational since 1995/1996
~$5 million/ site
~500 GB/radar/year
WSR-88D – Dates and other info

4. NEXRAD Overview 155 Sites (145 CONUS)
Puerto Rico, Guam, Hawaii, Alaska, etc.
Radar Coverage in CONUS

5. Level II Reflectivity Spectral Width Notch Velocity
NEXRAD Data
Level III
20 + Products
Reflectivities
Radial Velocities
Wind Profile
Vertical Integrated Liquid
Surface Rainfall
Precipitation
Level II
Reflectivity
Spectral Width
Notch Velocity
NEXRAD Level II and Level III
Volume Scans
1o x 1km
5-6 minutes rainfall mode
Derived Products
Polar and Rectangular Gridded
From 5,6 minute to Hourly and Storm Event

6. WSR-88D Radar Data Services NCDC Radar Archives:
Entire NEXRAD Period of Record:
1991 – Present
1.5 Petabytes – 334,652 DVDs
Increases at 480 Gigabytes/Day
Potential increase to 6,656 Gigabytes/Day
NEXRAD Level II
4,786 Requests
658 Unique Users
Total Volume serviced – 39.9TB
Annual Volume Ingested – 72TB
NCDC Radar Archives and Request
NEXRAD Level III
2,421 Requests
378 Unique Users
Total Volume serviced – 1.4TB
Annual Volume Ingested – 2TB

7. Precipitation Products
Precipitation products available at NCDC
Name
Span
Time
Space
How to get
NEXRAD Level II
1995 – present
5min
1deg x 1km
Online order
NEXRAD Level III
5min to Hourly
1deg x 1km – 4km nominal
MPR
1996 – present
Hourly
4km HRAP
THREDDS
Q2 – QPE-SUMS
2005 – present
5 minute
1 deg x 1 km
GPCP
present
Monthly, Daily
1 deg – 2.5 deg
ftp
DSI 3200
1900 – present
Daily
In-situ
DSI 3240
1970 – present
CRN
2000 – present
In –situ
HADS
Model Data
Varies
THREDDS -
NOMADS
Radar-
Based
Satellite-
Based
Precipitation Products at NCDC
In-Situ
Model

8. WSR-88D Radar Data Services Services include:
Direct access to NEXRAD Digital Data, Data Visualization, Analysis and Export Tools via the NCDC radar resources web page
URL:
Spatial Search
Temporal Search
File Search
Order Data
NEXRAD Data Access

9. Software Applications
Java NEXRAD Viewer
Examples and Figures from Steve Ansari

10. Software Applications
Java NEXRAD Viewer
Filter NEXRAD Export Data
Export NEXRAD to shapefiles, ESRI Grids, GrADS (coming soon: NetCDF, GeoTIFF & HDF)
Export Simple Math Results
Examples and Figures from Steve Ansari

11. High-Resolution Microwave-Based Precipitation Analysis
R&D
Quarter degree spatial, daily temporal analysis (Tom Smith, Ralph Ferraro, Yin, and others)
Microwave-based precipitation
AMSU, SSMI, AMSR-E, TRMM satellites, and gauge data
May augment with IR data to fill gaps
Latest MW algorithms for consistency
Developed an OI of MW and gauge observations
Estimation of error and scale OI statistics
Bias-adjustment method may be applied to product
GPCP work – Tom Smith and others at CICS/ESSIC

12. NOAA Multi-sensor QPE – Vision
Rain Gauge Data
Multisensor Precipitation Reanalysis (MPR)
Real-Time Multisensor QPE
NWS
NCDC
OAR/NSSL
Radar Data
NOAA Multisensor QPE Products & Services
Satellite Data
NESDIS/ORA
Other OAR Labs
NOAA QPE vision wrt NWS – NCDC - NSSL
External Partners
NWP Model Output Data
Lightning Data

13. Multi-Sensor Precipitation REANALYSIS
Complete Rain Gauge Data
Additional NWP Model Output
National Multisensor Precipitation Reanalysis
Reanalysis Products
Additional Satellite Data
Customers
NCDC Archive*
WSR-88D Level II Data
National Reflectivity Mosaic
Customers
CRAFT
Real-Time Products
Rain Gauge Data
National Multisensor QPE
Multi-sensor Precip Reanalysis benefits from real-time analysis
NWP Model Output
REAL-TIME ANALYSIS
NMQ
Lightning Data
Satellite Data
* Level II and Level III

14. Multi-Sensor Precipitation REANALYSIS
Why precipitation?
Critical climate variable through water cycle
Critical weather and water variable
Why multisensor?
Improves accuracy, resolution, coverage
Why reanalysis?
Affords more complete and better quality-controlled input data, and “best” scientific algorithms available
Can provide consistent high-resolution high-quality products
Why now?
High-resolution high-quality precipitation data (both historical and real-time) critically needed for water management … among others.
A decade of operational experience with real-time multisensor quantitative precipitation estimation (QPE)
Experience with limited-scope/scale multisensor precipitation reanalysis
National Mosaic and Quantitative Precipitation Estimation (NMQ) Project
MPR Justification

15. Multi-Sensor Precipitation REANALYSIS
Applications
Drought
Flood Management
Flash Flood Prediction
Water Supply
Transportation
Emergency Management
Agriculture
Debris Flows
Ecosystems Management
Hydrologic Design
Research
MPR
Multi-sensor product
High Resolution
Unbiased
Continental U.S
Customers
NWS
NOAA
Federal Agencies
Tribal Agencies
State Agencies
Local Agencies
Private Sector
Academia
Hydrologic, Environmental Engineers
MPR uses, customers

16. Multi-Sensor Precipitation REANALYSIS
Research to Operations
Customer Feedback
2005
2006
2007
Operational ?
Reanalysis
Research
Regional Product
Development
CONUS Product
Distribution
Product
Re-Development
New Data Sources
MPR Research to Operations
Product Dissemination – THREDDS Data Server

17. Precipitation products can help meet Phase II Objectives
NEXRAD and GEWEX
Precipitation products can help meet Phase II Objectives
Research quality data sets
Biases addressed and Uncertainty characterized
Energy and Water Cycle contribution to Climate
Major input to Energy and Water Budget studies
Space-Time characteristics of predictability of key variables
Data resolution affords for assessing space-time characteristics
Seasonal prediction of water and energy cycle variability
Long term allows for intra and inter annual studies
Assess climate prediction and global change
Can be input or benchmark for climate studies
Connect high resolution precip to GEWEX

18. WGPRN Data Format Data Transmission Archive Data Access
Determine the feasibility of producing common precipitation products from radar networks for a common time period.
Data Format
Data Transmission
Archive
Data Access
Resolution (Space and Time)
Algorithms
Issues related to radar networks in a common system

19. WGPRN Common Data Model Visualization File Format &Analysis #1 CDM
NetCDF file
File Format #2
OpenDAP Server
File Format #N
WCS Service

20. Possibilities and Associated Issues
WGPRN
Possibilities and Associated Issues
Band
Doppler Capabilities
Data Processing
Base Data
Data resolution
Data Transmission
Data format
Data Archive
C,X,S etc.
Yes, No
Radar Product Generator
Level II data (Z,V,W)
1o by 1km
NOAAPort
Standards
National Archive Center
Attenuation
Severe Weather
Internal Standard
Variables
File size
Data Transmission
CDM
Central Location
Example at NCDC
Agreements with Canada, Mexico, Korea

21. Conclusions 150 NEXRAD sites
Data format, organization, management
Provide for high resolution precipitation estimates
Space scales 4km and less
Temporal scales hourly and less
Archive is 10+ years
Allows longer term investigations
Current Reanalysis project
CONUS to other Continental-Scale implementations
Common Data Format
Data Archive
Data Transmission
Data Accessibility