Slide 1 Tennessee Tech University by pengtt

VIEWS: 4 PAGES: 28

									     Environmental Application of
       Remote Sensing: CE 6900
Course Instructor: Dr . Faisal Hossain (Associate Prof.)




                              Tennessee Technological University
               Department of Civil and Environmental Engineering
SOIL MOISTURE
  SATELLITES
     By: Abebe Gebregiorgis
                           Outlines
• Soil Moisture Active and Passive Satellite (SMAP) – NASA
   –   Introduction
   –   Mission Imperative Overview
   –   Scientific Objectives
   –   Scientific Overview
   –   Application Overview
   –   Current status
• Soil Moisture and Ocean Satellite (SMOS) – ESA
   –   Mission Imperative Overview and Scientific Objectives
   –   Scientific Overview
   –   Application Overview
   –   Current status
• Summary
Soil Moisture Active
Passive (SMAP) Satellite
                Introduction
• SMAP - both active and passive sensors
     • L-band radiometer – (passive sensor )
     • L-band radar – (active sensor)


• Designed to provide
  – Global Soil moisture
  – Freeze/thaw
                 Mission
• to provide global measurements of
  soil moisture and freeze/thaw state
  via L-band radar and radiometry so as
  to
      –Improve estimates of land surface
       evaporation,
      –Have good understanding of land-
       atmosphere water and energy exchange
           Specific objectives
• Understand processes that link the terrestrial
  water, energy and carbon cycles
• Estimate global water and energy fluxes at the
  land surface
• Enhance weather and climate forecast skill
• Develop improved flood prediction and drought
  monitoring capabilities
           Scientific Overview
Artistic rendition of the SMAP spacecraft
                               Scientific overview …
• Orbit
  – Orbit Altitude: 670 km
    (450 to 700 km)
  – Inclination: 98 degrees,
    sun-synchronous
  – Local Time of Ascending
    Node: 6 pm
  – SMAP will make
    measurements from a
    6am/6pm sun-
    synchronous polar orbit
                           Scientific overview …


• Configuration:
  Conically-scanning
  reflector
  – Diameter: 6 meters
  – Shared by both radar
   and radiometer
                              Scientific overview …



• Configuration:

  – 1000 km wide swath
  – Scanning system: Along track scanning ???
   SMAP Satellite’s swath path 1
shows the initial path of the satellite
           SMAP Satellite’s swath path 2
shows the swath path illustrate the scanning pattern
                 of the antenna
      SMAP Satellite’s swath path 3
shows the swath path with more extensive
               coverage
SMAP measurement geometry
             Data Products




• Schematic representation of passive (left) and
  active (right) microwave interaction with soil and
  vegetation
                                  Scientific overview …


• Configuration:

  – Resolution:
    • 40 km radiometer
    • 1-3 km SAR (Synthetic Aperture Radar)
    • 10 km – combined product
  – Rotation rate: 14.6 RPM
  – Beam efficiency: 90%
                Data Products

• Soil Moisture
  – L-Band Radiometer (1.41 GHz)
     • Resolution = 40 km
  – L-Band Radar (1.26 GHz)
     • Resolution = 10 km
• Freeze/Thaw
  – L-Band Radar (1.26 GHz)
  – Resolution 3 km
                 Data Products

• Sampling duration
  – 6 am/ 6 pm
• Revisit duration
  – Global = 3 days
  – Boreal = 2 days
• Mission life
  – Minimum = 3 years
          Application Overview
 • Hydrological Hazards Applications:
    – Drought and Flood
 • Ecosystem Services Applications
    – Agricultural Productivity
 • Weather Forecast Applications
 • Climate Prediction Applications
 • Human Health Applications
                      Status
SMAP launch is currently targeted for 2014
SOIL MOISTURE AND OCEAN
 SALINITY (SMOS) SATELLITE
                     Introduction
• European Space Agency (ESA)

• The SMOS mission is a direct response to the
  current lack of global observations of soil
  moisture and ocean salinity

• It objectives are to:
  – globally monitor surface soil moisture over land surfaces,
  – globally monitor surface salinity over the oceans, and
  – Improve the characterization of ice and snow covered
    surfaces.
          Scientific overview
• altitude of 755 km
• view an area of almost 3000 km in diameter.




                                      Click here
                                      SMOS
•   Launch: 2009
•   Duration: Minimum 3 years
•   Instrument: Microwave Imaging Radiometer
•   Instrument concept:     Passive microwave
•   Frequency:         L-band (21 cm -1.4 GHz)
•   Number of receivers:     69
•   Spatial resolution: 35 km
•   Temporal resolution: 3 days revisit at Equator
•   Swath: 3000 km
         Scientific application
• Soil moisture
• Ocean salinity


           Current Status
                 SMAP & SMOS
• Do they have overlapping mission?
• May new science opportunities arise if data from
  SMAP and SMOS mission are combined ?

Facts:
• SMOS will explore a potential technology but will provide
  only a 35 km resolution
• SMAP will explore a potential technology and different
  instrument design and will provide a 10 km resolution
• SMOS - ocean salinity, whereas SMAP -freeze/thaw
                                   Evolution of SMOS & SMAP
                            Day
                                            SMOS         SMAP Radar-Radiometer
Resolved Temporal Scales




                                     Climate Applications


                           Week                             Weather Applications



                                             Evolution                             Carbon Cycle
                                             of L-Band                             Applications
                                             Sensing
                           Month


                                   100 km                   10 km                        1 km
                                               Resolved Spatial Scales
This material is extracted and compiled from
  • http://smap.jpl.nasa.gov/
  • http://www.esa.int/esaLP




 Thank You

								
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