The Remote Sensing Data Extraction Module

What is RESDEM?

RESDEM is a web based processing system for geospatial scientific data sets. Currently supported datasets via the online ordering application are: SSMI (Special Sensor Microwave/Imager), Topex/Poseidon, AMSR (Advanced Microwave Scanning Radiometer-EOS), and TRMM (Tropical Rainfall Measuring Mission). For imformation on the products Available look under the appropriate sections below.

SSM/I

The SSM/I sensor is carried aboard the Defense Meteorological Satellite Program (DMSP) satellites. It is a seven channel passive microwave radiometer operating at four frequencies onboard the Defense Meteorological Satellite Program (DMSP) series of polar orbiting satellites. SSM/I provides instantaneous rain rates on a global coverage at a spatial resolution of 0.51 Â 0.51 from 1987 to present. The SSM/I rainfall algorithm developed at NOAA utilizes the 85 V GHz channel to evaluate the scattering of upwelling radiation by ice particles within the rain layer. Precipitation rates are derived using relationships between rain fall and the amount of ice within the rain layer. The SSM/I data were downloaded from ftp://lake.nascom.nasa.gov/data/TRMM/Ancillary/ssmi.

Products Available

Rain Rate
Brightness Temperature
Delta T

  • Daily Averages (tiff)
  • Monthly Averages (tiff)
  • Yearly Averages (tiff)
Topex/Poseidon

Topex/Poseidon is an on going mission launched in 1992 as a joint venture between the National Aeronautics and Space Administration (NASA) and and the Centre National d’Études Spatiales (CNES) to map ocean surface topography. Measurements on this satelite are taken by two altimeters Topex operating at 5.3ghz and 13.6ghz and Poseidon operating at 13.65 ghz.

Products Available

Sea Surface Height
DBF/CSV File

AMSR

The AMSR-E on the EOS’ Aqua satellite launched on May 4, 2002, is a conically scanning total power passive microwave radiometer that measures microwave radiation (brightness temperatures) across 12 wavelength regions (12 channels) and at frequencies ranging from 6.9 to 89.0 GHz. Both horizontal and vertical polarized radiations are measured separately at each frequency (Njoku et al., 2003). The input brightness temperature data, corresponding to a 56 km mean spatial resolution, are re- sampled to a global cylindrical 25 km Equal-Area Scalable Earth Grid (EASE-Grid) cell spacing. The Aqua orbit is sun-synchronous with equator crossings at 1:30 P.M. and 1:30 A.M. The AMSR-E data were downloaded from NASA’s Distributed Active Archive System (DAAC) at http://daac.gsfc.nasa.gov.

Products Available

Soil Moisture
Vegetative Water Content

  • Daily Averages (tiff)
  • Monthly Averages (tiff)
  • Yearly Averages (tiff)
TRMM

The TRMM is a joint mission between the National Space Development Agency (NASDA) of Japan and the National Aero- nautics and Space Administration (NASA) of the United States as part of the Earth Observing System (EOS). TRMM provides global (501N–501S) data on rainfall using microwave and visible-infrared sensors. Instantaneous rainfall estimates are obtained every 3 h with a 0.251 Â 0.251 footprint. Launched in 1997, TRMM provides continuous coverage from 1998–present. The primary rainfall instruments of TRMM are the precipitation radar, TRMM micro- wave imager, and the visible/infrared scanner (Kummerow et al., 1998). The TRMM 3B42.v6 products were downloaded from NASA’s Distributed Active Archive System (DAAC) at http://daac. gsfc.nasa.gov for its entirety (1998–present).

Products Available

Rain Rate
Threshold Events

  • Daily Averages (tiff)
  • Monthly Averages (tiff)
  • Yearly Averages (tiff)
  • SWAT modeling DBF Files
AVHRR

The Advanced Very High Resolution Radiometer (AVHRR) is a space-borne sensor embarked on the National Oceanic and Atmospheric Administration (NOAA) family of polar orbiting platforms (POES). AVHRR instruments measure the reflectance of the Earth in 5 relatively wide (by today’s standards) spectral bands. The first two are centred around the red (0.6 micrometer, 0.5 THz) and near-infrared (0.9 micrometer, 0.3 THz) regions, the third one is located around 3.5 micrometer, and the last two sample the thermal radiation emitted by the planet, around 11 and 12 micrometers, respectively.

Products Available

  • Cloud Detection
  • NDVI
  • Reflectance