Applying Longterm SSMI Observations to Dust Storm Study

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Applying Long-term SSM/I Observations to Dust
Storm Study

• Jinyang Du
• USDA-ARS Hydrology Remote Sensing Lab
• Aug 27-29, 2007, Boulder

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Objectives

• Explore the potential role of microwave remote
  sensing in dust storm monitoring
• Use long-term microwave satellite observations to
  study the change of earth surface conditions
• Demonstrate the relationship between Microwave
  Indexes and ground surface parameters of dust
  storm source regions
• Scattering Index
• Polarization Index
• Impact of current and future microwave satellites
  on dust storm monitoring

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Special Sensor Microwave Imager (SSM/I)

• Seven-channel, four-frequency (19.35, 22.235, 37,
  and 85.5 GHz) microwave radiometer
• conically scanning
• Incidence angle 53 degree
• Data from SSM/I mounted on Defense
  Meteorological Satellite Program (DMSP) F13
  platform are used in the study
• (Data source NSIDC)

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Study Region- Ordos Plateau of China

• 3720'4050'
• 10624'11128'
• A transitional zone of arid to semi-arid climates
• One of the Asian dust-storm source regions

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Scattering Index

• Precipitation and Snow are masked out
• Scattering Index can be used to evaluate feature
  scattering properties
• Dry loose soil particles can be strong scatterers

SI451.88-0.44Tb_19v-1.775Tb_22v0.00574Tb_22v
Tb_22v Tb_85v (Ferraro et al.,
1994)
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Polarization Index
Global Polarization Index Map
Global NDVI Map
PI(Tb_v-Tb_h)/(Tb_vTb_h)
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Scattering Index (April, Erdos Plateau)
Compare SI and Number of dust-storm days observed
from meteorology station
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Polarization Index (May, Erdos Plateau)
Compare PI and Number of dust-storm days observed
from meteorology station
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Summary

• Microwave remote sensing can provide unique
  ground surface information
• SI and PI derived from SSM/I observations can be
  used to monitor the surface condition of sand
  storm regions
• Long-term earth observations from current
  microwave satellites SSM/I, AMSR-E, WindSat and
  future L-Band satellites (SMAP, SMOS) will help
  to understand the change of land surface