Real Time Data

Transmission of NOAA Tail Doppler Radar Data for 2010 & 2011 Hurricane Seasons

Introduction

The NOAA WP-3D aircraft provide X-band Doppler/reflectivity measurements of tropical storms and cyclones. Doppler measurements from volume backscatter precipitation profiles can provide critical observations of the horizontal winds as the precipitation advects with these winds. In 2010, NOAA NESDIS, NOAA AOC, NOAA HRD and Remote Sensing Solutions teamed to capture these profiles and send the radial Doppler profile observations to National Weather Service in near real-time over satellite communication data link. The design of this transmission system included features to enhance the reliability and robustness of the data flow from the P-3 aircraft to the end user. The end objective is to provide these Doppler profiles, and other atmospheric and oceanic observations, in a routine and automated fashion to NWS and others in the forecasting community for operational utilization in support of hurricane forecasting and warning. It is important to note that the actual radial Doppler profile data was transmited in real time, as opposed to images of the data.

Project Objectives

Real-time Radar / Data Server:

  • Aircraft-ground data communication server provides in near real-time:
    • Processed Tail Doppler Radar Profiles (Doppler, spectral width, reflectivity factor)
    • Lower Fuselage Reflectivity Profiles
    • Scientific Data (e.g. AXBT profiles)
  • Weather Message Processor provides:
    • Radar meta data files to NCO as the data becomes available. Will contain processed Tail Doppler and/or Lower Fuselage radar profiles.
    • Scientific and AXBT meta data files.
    • Quality of service implemented that monitors aircraft-ground communications and automatically handles disruptions.

Real-Time Data Transmission from the NOAA P-3 Aircraft

TDR Doppler profiles made available in near real-time to NWS/NCEP/EMC in BUFR format:

  • HRD processor generated quality controlled TDR Doppler profiles in near real-time.
  • Doppler profiles were automatically transferred to the aircraft server.
  • Aircraft server autonomously translated Doppler profiles in real-time into compress payloads and transmitted them from N42 and N43 to the ground server over the satellite data link.
  • Autonomous ground server received data payloads, processed the payloads to generate radar weather message files and transfer them to the TOC where they were converted to BUFR format and made available to NWS/NCEP/EMC.
  • A dual "heartbeat" was implemented on the satellite data link to maximize data transfer reliability and pass status information.
  • Both P-3 aircraft have been upgraded to the Swift Broadband SATCOM system

Real Time Radar Profile Data Processing

Airborne Server:

  • Receives data packets from Sigmet processor & extracts radar profiles.
  • Archives radar profile and ancillary data.
  • For lower bandwidth data links, further profile data processing implemented (i.e. range gate averaging, bit remapping, compression, Gamache’s Doppler processing) to reduce data rates to within link budget.
  • Build compressed packetized data and transmits to ground server.
  • Transmits data as soon as it becomes available.

Ground Server:

  • Receives packetized data, and rebuild radar profile data.
  • Implement quality of control and ground processing of radar profiles.
  • Build NCO standardized radar files and send to TOC server as they become available.
  • Implements subscription service where client applications and users can subscribe for data. Relay data packets to subscribed users.

Real Time Radar Display



Real Time AXBT Profile Plot



Real Time Data Processing Flow Chart

Data Processing Flow Chart

Enhancements made for 2011 Hurricane Season

For 2011, transmission of high resolution data to NWS/NCEP/EMC was implemented. These data can be sent to other facilities such as HRD and NHC for additional real-time ground processing and visualization. This includes reflectivity, Doppler and spectral width profiles from the TDR, reflectivity profiles from the LF Radar, AXBT temperature-depth profiles and 1 Hertz science data. The examples on this page are to illustrate the resolution and types of data that will be transmitted to the ground for distribution. NOTE: The raw data is transmitted, not just images, allowing maximum flexibility in interpreting the data.

Tail Doppler Radial Velocity Plot



This is a cooperative effort between: AOC, NCEP/NCO, NWS/TOC, NESDIS, AOML/HRD, NCEP/EMC, and Remote Sensing Solutions.