Summary of Global Tropospheric Wind Sounder GTWS Technology Roadmap

1
Summary of Global Tropospheric Wind Sounder
(GTWS) Technology Roadmap

• Ken Miller, Mitretek Systems
• June 23, 2003

2
Agenda

• Purpose
• Vital National Need
• Multi-year Interagency Program Recommendation
• Status
• Reference Designs
• DWL Alternatives
• Roadmap
• Summary and Recommendations
• Acknowledgments

3
Purpose

• GTWS Acquire global wind profiles
• Roadmap Focus GTWS activities
• Draft roadmap submitted for NASA and NOAA
  consideration
• Based on multi-agency input
• High level
• Important unknown factors
• Resource needs will vary widely depending on
  approach and rate of technology progress

4
Vital National Need

• Global winds are the number 1 unmet observational
  requirement for global weather forecasts (NPOESS
  IPO)
• NASA Earth Science Directorate plans include
  global tropospheric wind observation and
  assimilation
• Wind data will support missions of NOAA, NASA,
  DOD, FAA, FEMA, Department of Homeland Security
• Benefits to government, industry, and citizens
  include
• Weather forecasting
• Atmospheric and climate studies
• Transportation
• Air quality forecasting
• Shipping
• Agriculture
• Construction

5
Multi-year InteragencyProgram Recommendation

• Participating agencies
• Prepare a long term plan
• Define appropriate agency roles
• Share funding, staff, and other resource
  commitments
• Share user benefits

6
Status

• NOAA/NASA partnership since 2000
• Guided by GTWS Executive Steering Committee
  (GESC)
• Investigate data acquisition
• GESC action item to prepare this roadmap
• Data requirements
• OSSEs
• Requirements validation
• Benefit quantification
• Favorable preliminary benefit-to-cost ratios
• Reference instruments and missions
• Assess technology readiness
• Support evaluation of alternatives
• Preliminary cost estimates
• NASA Laser Risk Reduction Program (LRRP)

7
Status (continued)

• Instrument activities
• NASA, NOAA, IPO and others demonstrating ground
  and airborne DWLs
• IPO funding airborne work on calibration/validatio
  n  
• Related international missions
• Japanese National Space Development Agency
  (NASDA)
• European Space Agency (ESA)

8
Status - Measurement Concept
7.7 km/s

• Vertical resolution range gates
• 45 o nadir angle
• Scan through 8 azimuth angles
• Fore and aft perspectives in TSV
• Move scan position 1 sec
• No. shots averaged 5 sec prf
• 4 ground tracks

Aft perspective
45
585 km
400 km
45
Horizontal TSV
414 km
7.2 km/s
290 km
290 km
9
Status - Instrument Concepts
Belt Drive
Radiator
Telescope with Sunshade
Rotating Deck
Component Boxes
Direct
Radiator
Component Housing
Coherent
Note Large solar arrays not shown
10
Status - DWL Alternatives

• Each alternative has advantages
• Direct detection
• Coherent
• Hybrid
• Hybrid combines complementary aspects of coherent
  and direct detection
• Possibly the most rapid and economical approach
• May complicate mission and spacecraft issues
• IPO is sponsoring a hybrid DWL feasibility study

11
Status -Reference Designs

• Need space-qualified DWL capable of meeting data
  requirements
• Coherent and direct detection reference designs
  completed
• Large and heavy spacecraft
• Massive optical components
• Very high electrical power consumption
• Hybrid
• Promising point design supported by IPO
• Reference design not completed

12
Roadmap - Near Term Issues

• Technology development needed
• Lasers
• Detectors
• Low-mass telescopes
• Scanners
• Momentum compensation
• Benefits and sensitivity to data requirements
• Hybrid reference design
• DWL alternatives - trade studies
• Impacts on data products from atmospheric
  properties, DWL alternatives, and spacecraft
  mechanics
• Calibration and validation

13
Roadmap

• Time scale depends on
• Funding and resource decisions
• Technology advances
• Longest lead time estimates
• Flight qualified lasers 4 years
• Electro-optic scanners (alternative to rotating
  telescope scanners) up to 6 years
• Laboratory, ground, air, and space demonstrations
  will reduce risk and cost

14
Roadmap Major Tasks and Phasing
No time scale assigned pending planning decisions
15
Roadmap Task Descriptions

• 1. GESC Oversight- coordinate interagency
  support and management
• 2. Data Requirements and Data Utility
  Preparedness
• Benefits, sensitivity to data requirements
• Data assimilation
• Revised data requirements, if justified
• 3. Achieve Technology Readiness
• Lasers
• Detectors
• Low-mass telescopes
• Scanners
• Momentum compensation

16
Roadmap Task Descriptions (continued)

• 4. Architecture- system engineering and
  architecture for optimal design and acquisition,
  e.g.
• Trades between data requirements and technology
• Hybrid reference design
• Trades between DWL alternatives
• Atmosphere and lidar models
• Impacts on data products from atmospheric
  properties, DWL alternatives, and spacecraft
  mechanics
• Calibration and validation
• 5. Ground Demonstration- prototype DWLs

17
Roadmap Task Descriptions (concluded)

• 6. Air Demonstration
• Selected DWL approach
• Variety of atmospheric conditions
• 7. Space Demonstration
• Prove ability to meet data requirements from
  orbit
• Shuttle, International Space Station, DOD Space
  Test Program mission, or other platform
• 8. Operational Mission
• Acquire, launch, and operate end-to-end system
• Produce and distribute data products
• Orbit a second instrument, as required, to meet
  temporal and spatial resolution requirements

18
Lower Level Roadmaps
19
Roadmap - Preliminary Resource Estimates

• Cost estimates for internal government use
• Depend on a wide range of contingencies
• Inference from experience is not very accurate

20
Roadmap First Cut Fraction of Relative Cost by
Task
Fraction of total cost
21
Summary and Recommendations

• Promising preliminary benefit to cost ratio
• Requires technology advances
• Architecture studies
• To drive future work
• Potential savings on development, space
  demonstration, and mission
• Interagency team
• Near term activities

22
Acknowledgments
Farzin Amzajerdian (NASA/LaRC) Robert Atlas
(NASA/GSFC) Wayman Baker (NOAA/NWS) James Barnes
(NASA/LaRC) David Emmitt (Simpson Weather
Associates) Bruce Gentry (NASA/GSFC) Ingrid Guch
(NOAA/NESDIS) Michael Hardesty (NOAA/OAR) Michael
Kavaya (NASA/LaRC) Stephen Mango
(NPOESS/IPO) Kenneth Miller (Mitretek
Systems) Steven Neeck (NASA/HQ) John Pereira
(NOAA/NESDIS) Frank Peri (NASA/LaRC) Upendra
Singh (NASA/LaRC) Gary Spiers (NASA/JPL) James G.
Yoe (NOAA/NESDIS)