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NEXRAD Data and Products at NCDC

National Climatic Data CenterBrian NelsonJohn Bates

Steve AnsariStephen Del Greco

NOAA/NESDIS

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Outline

• Brief Overview of NEXRAD

• Data at NCDC

• Products at NCDC

• Applications (software)

• Product development

• GEWEX connection

• Working Group on Precipitation Radar Networks

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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

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NEXRAD Overview

• 155 Sites (145 CONUS)

• Puerto Rico, Guam, Hawaii, Alaska, etc.

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NEXRAD Data

Level II• Reflectivity• Spectral Width• Notch Velocity

Level III• 20 + Products• Reflectivities• Radial Velocities• Wind Profile• Vertical Integrated Liquid• Surface Rainfall• Precipitation

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

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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 II4,786 Requests 658 Unique UsersTotal Volume serviced – 39.9TBAnnual Volume Ingested – 72TB

NEXRAD Level III2,421 Requests 378 Unique UsersTotal Volume serviced – 1.4TBAnnual Volume Ingested – 2TB

WSR-88D Radar Data Services NCDC Radar Archives:

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Precipitation Products

Name Span Time Space How to get

NEXRAD Level II

1995 – present 5min 1deg x 1km Online order

NEXRAD Level III

1995 – present 5min to Hourly 1deg x 1km – 4km nominal

Online order

MPR 1996 – present Hourly 4km HRAP THREDDS

Q2 – QPE-SUMS

2005 – present 5 minute 1 deg x 1 km Online order

GPCP 1979 - present Monthly, Daily 1 deg – 2.5 deg

ftp

DSI 3200 1900 – present Daily In-situ Online order

DSI 3240 1970 – present Hourly In-situ Online order

CRN 2000 – present Hourly In –situ Online order

HADS 1996 – present Hourly In-situ Online order

Model Data Varies Varies Varies THREDDS -NOMADS

Precipitation products available at NCDC

Radar-Based

In-Situ

Model

Satellite-Based

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Direct access to NEXRAD Digital Data, Data Visualization, Analysis and Export Tools via the NCDC radar resources web pageURL: http://www.ncdc.noaa.gov/oa/radar/radarresources.html

Spatial Search

Temporal Search

File Search

Order Data

WSR-88D Radar Data Services Services include:

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Software Applications

Java NEXRAD Viewerhttp://www.ncdc.noaa.gov/oa/radar/radarresources.html

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Software ApplicationsJava NEXRAD Viewer

• Filter NEXRAD Export Data

•Export NEXRAD to shapefiles, ESRI Grids, GrADS (coming soon: NetCDF, GeoTIFF & HDF)

•Export Simple Math Results

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R&D

High-Resolution Microwave-Based Precipitation Analysis

Quarter degree spatial, daily temporal analysis (Tom Smith, Ralph Ferraro, Yin, and others)

Microwave-based precipitationAMSU, SSMI, AMSR-E, TRMM satellites, and gauge

dataMay augment with IR data to fill gaps

Latest MW algorithms for consistencyDeveloped an OI of MW and gauge observations

Estimation of error and scale OI statisticsBias-adjustment method may be applied to product

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NOAA Multi-sensor QPE – Vision

Rain Gauge Data

Satellite Data

Radar Data

NWP Model Output Data

Lightning Data

External Partners

NWS

NCDC

NESDIS/ORA

OAR/NSSL

Other OAR Labs

NOAA Multisensor QPE

Products & Services

Real-Time Multisensor

QPE

Multisensor Precipitation

Reanalysis (MPR)

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WSR-88D Level II Data

Rain Gauge Data

Satellite Data

NWP Model Output

Lightning Data

National Reflectivity

Mosaic

National Multisensor

QPE

Complete Rain Gauge Data

Additional Satellite Data

Additional NWP Model

Output National Multisensor Precipitation Reanalysis

Reanalysis Products

Real-Time Products

Customers

NMQREAL-TIME ANALYSIS

Customers

NCDC Archive*

CR

AF

T

* Level II and Level III

Multi-Sensor Precipitation REANALYSIS

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Why precipitation?Critical climate variable through water cycleCritical 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 availableCan 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 reanalysisNational Mosaic and Quantitative Precipitation Estimation (NMQ) Project

Multi-Sensor Precipitation REANALYSIS

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Applications

Drought

Flood Management

Flash Flood Prediction

Water Supply

Transportation

Emergency Management

Agriculture

Debris Flows

Ecosystems Management

Hydrologic Design

Research

Customers

NWS

NOAA

Federal Agencies

Tribal Agencies

State Agencies

Local Agencies

Private Sector

Academia

Hydrologic, Environmental Engineers

MPR

Multi-sensor product

High Resolution

Unbiased

Continental U.S

Multi-Sensor Precipitation REANALYSIS

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Research to Operations

Product Dissemination – THREDDS Data Serverhttp://eclipse.ncdc.noaa.gov:9090/thredds/dodsC/radar/catalog.html

Customer Feedback

2005 2006 2006 2007 Operational ?

Reanalysis Research

Regional ProductDevelopment

CONUS ProductDistribution

ProductRe-Development

New Data Sources

Multi-Sensor Precipitation REANALYSIS

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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

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WGPRN

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

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WGPRN

Common Data Model

File Format#N

File Format#2

File Format#1

Visualization&Analysis

NetCDF file

OpenDAP Server

WCS Service

CDM

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WGPRN

Possibilities and Associated Issues

• C,X,S etc.

• Yes, No

• Radar Product Generator

• Level II data (Z,V,W)

• 1o by 1km

• NOAAPort

• Standards

• National Archive Center

• Band

• Doppler Capabilities

• Data Processing

• Base Data

• Data resolution

• Data Transmission

• Data format

• Data Archive

• Attenuation

• Severe Weather

• Internal Standard

• Variables

• File size

• Data Transmission

• CDM

• Central Location

Example at NCDC• Agreements with Canada, Mexico, Korea

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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

http://www.ncdc.noaa.gov/oa/radar/radarresources.html