Unidata - To provide the data services, tools, and cyberinfrastructure leadership that advance Earth system science, enhance educational opportunities, and broaden participation. Unidata
    •      
  advanced  
 

Participants:

Harry Edmon, Univ of WA
Rit Carbone, USWRP
Woody Roberts, FSL
Richard Chinman, IITA
Dave Fulker, Unidata
Linda Miller, Unidata
 

Dave Fulker called Ken Crawford, a Unidata Policy Committee member, to invite him or a OU or CAPS representative to attend the meeting, but there was an important CAPS meeting that conflicted with the date.

Background:

Dave provided an overview of activities leading to the meeting.  He emphasized the Users Committee recommendation that Unidata act on behalf of the Unidata sites to access Level II data from the radars and make it available to all institutions that are interested in using the data. Fulker and Miller met with several NWS officials to discuss the access and distribution of the data and were encouraged by the NWS to pursue the use of the Level II data among university institutions.  During that meeting, it was agreed that an amendment would be made to the current RIDDS arrangement to allow redistribution of the Level II data for use in education and research activities.

Direct Connection to Local WSR-88D:

The process for obtaining the direct connection to a local radar is a letter to the Regional NWS Headquarters requesting the connection with a short proposal on a collaborative project using the data.

RIDDS is the system that is used to provide access to the local radar and distribution of the data to a single point.  It requires two Sun workstations placed at the WSFO site. One is referred to as the "RIDDS" station and is directly connected to the RPG and a Ethernet hub. The second station is the one that can be modified by the institution and is connected to the Ethernet hub.
 
The following university sites have a RIDDS agreement for direct connection to their local WSR-88D radars:

        Univ of WA
        Univ of CA, Santa Cruz
        Univ of NV, DRI
        Naval Post Graduate School
        NCSU
        MIT
        TAMU
        Penn State
        SUNY-Albany
 

Radar Interface & Data Distribution System (RIDDS)

Harry defined the characteristics of the RIDDS system  in Seattle. The two Suns are described above. The station running the RIDDS has about 32 MB of memory.  The site is archiving about 3 weeks of data.  The experience in Seattle has been about 9.8 MB of data with a volume scan every 6 minutes in interesting weather and every 10 minutes in normal conditions. There are 4 products with 17 tilts.  Bob House is using Zebra (NCAR product) to view the data. Various compression schemes were tested with worst being 4:1 and best being 50:1.  The average is 8:1 and using GZIP, it is 10:1.  The RIDDS is a common interface to the Radar Products Generator (RPG), created by the Operational Support Facility (OSF) in Norman, OK.

Woody reported that in 18 months the RIDDS will become obsolete.  Bob Saffle, NWS, will be moving the system to an open RPG system with 4 ports on the Ethernet with Level II data.  They will be using the TCP/IP protocol.

Forecast System Lab (FSL)

Woody Roberts provided an overview of FSL related activities.  FSL is accessing three radars; Cheyenne, Goodland and Denver.  The RIDDS system has cost them about 13K for each connection.  FSL is using a SPARC2 and runs a 5km Cartesian grid.  FSL ignores the spectrum width.  They are creating a mosaic from the 3 radar systems.  He indicated that modelers want the radial winds. The Cartesian grid is 500m using 2km nested grid. He mentioned that AWIPS would carry a subset of products from the NEXRAD sites.

Next Steps

It was agreed that a co-sponsored workshop should be held in the September-October
time frame to discuss product definition and how to proceed.  The co-sponsors would be the USWRP and Unidata.  Rit Carbone pointed out that there is a plan for 120M for a 5 year research initiative between 2000-2005

There are several groups and communities who are interested in the products from the RPG, including hydrology, NCAR's RAP, ATD, MMM etc.

We will begin a proof of concept which will include the University of Washington, FSL,
and perhaps others.  It was suggested that we contact Richard Oye, ATD, to gather information about related activities.

Fulker emphasized the use of the vBNS or Next Generation Internet (NGI) for experimenting.  Harry said that Washington has 2 or 3 T3s and their connection has been very effective in moving the data using the LDM/IDD technology thus far.

Institutions or contacts mentioned for a prototype experiment were:
        Princeton, Jim Smith
        Florida State
        UCLA
        San Jose

Post Scripts to this report:

Exchange between Woody and Dave proposing:

  1.   Access for FSL & Washington to FSL high speed network
  2.   Porting/installation of the Washington code at FSL
  3.   Washington & FSL ingest routines developed to handle each other's data
  4.   Create rectilinear products  at the point of ingest that are free of information loss, but that permit recipients to subscribe to _subsets_ of each volume scan (Rit's description)
  5.   Investigate the applicability of Dick Oye's software
Mike Carelli, NWS, called to say that testing can begin, but there is a need to be very cautious with the use of the data for education and research activities.  The NWS and Tri-Agency group will provide a formal amendment to the RIDDS agreement soon.  It will be passed to Unidata, in draft form, for review and comment.
 
Linda Miller
External Liaison                                      Telephone: (303) 497-8646
UCAR/Unidata Program Center             Fax: (303) 497-8690
P.O. Box 3000                                       E-mail: lmiller@unidata.ucar.edu
Boulder, CO 80307-3000                       http://my.unidata.ucar.edu/

 
 
 
 
  Contact Us   •   Site Map   •   Search   •   Terms and Conditions   •   Privacy Policy   •   Participation Policy
 
National Science Foundation (NSF) UCAR Office of Programs University Corporation for Atmospheric Research (UCAR)   Unidata is a member of the UCAR Office of Programs, is managed by the University Corporation for Atmospheric Research, and is sponsored by the National Science Foundation.
P.O. Box 3000   •   Boulder, CO 80307-3000 USA   •   Tel: 303-497-8643   •   Fax: 303-497-8690