Getting-Started Guide

1. What does Remote Sensing Systems offer?

2. What is remote sensing?

3. What data are available from Remote Sensing Systems?

4. Which data set should I use?

5. What data formats are available from Remote Sensing Systems?

6. Where can I get Remote Sensing Systems data?

7. How can I view the data before I download it?

8. How do I read the data?

9. I need more help.

 

1. What does Remote Sensing Systems offer?

Remote Sensing Systems (RSS) is a world leader in processing and analyzing microwave data collected by satellite microwave sensors. We provide research-quality geophysical data to the global scientific community. Learn more about us.

 

2. What is remote sensing?

Remote sensing, as it pertains to our research at Remote Sensing Systems, refers to observations made from a distance, using satellites orbiting the earth.  These satellites are designed to observe the earth at specific wavelengths, or frequencies, in the electromagnetic spectrum. At Remote Sensing Systems, we primarily use satellite data from the microwave region of the electromagnetic spectrum.


Image provided courtesy of Victor Blacus / CC-BY-SA-3.0

 

Microwaves are a type of electromagnetic radiation emitted and reflected by the Earth and atmosphere.  Microwave radiation interacts with the atmosphere.  The electromagnetic spectrum figure above shows microwaves have frequencies between that of radio/TV and infrared radiation. Many types of remote sensing instruments measure microwaves.  We process data from three types here at Remote Sensing Systems: Radiometers, Scatterometers, and Sounders.

Radiometers (SSMI/SSMIS, TMI, AMSR, AMSR2, WindSat, GMI) passively measure microwave radiation naturally emitted from the surface of the earth.  Different amounts of radiation are emitted from land surfaces versus water surfaces.  Over the oceans, a radiative transfer model and physical algorithms are used to retrieve geophysical parameters: surface wind speed, atmospheric columnar water vapor, cloud liquid water, rain rate and sea surface temperature.  To measure sea surface temperature, lower frequency measurements are needed.  Not all radiometers can measure the lower frequencies.

Scatterometers (NSCAT, QuikSCAT, ASCAT) are active microwave instruments that emit microwave pulses to the surface of the earth and measure the reflected/returned energy.  A geophysical model function is used to extract surface wind speed and direction from the returned energy.

Sounders (MSU, AMSU) make use of multiple channels and frequencies to measure the microwave radiation originating from different heights in the atmosphere. Using a weighting function, microwave sounder data can be used to determine the atmospheric temperature for these heights in the atmosphere, effectively creating an atmospheric profile of temperature.

 

3. What data are available from Remote Sensing Systems?

Instrument data available at Remote Sensing Systems are listed in the table below.

Instrument

Full Name

Satellite(s)

Geophysical Parameters from RSS

Time Period Available

SSM/I

Special Sensor Microwave Imager

DMSP F8 to DMSP F15

Wind speed, water vapor, cloud liquid water, and rain rate over oceans

1987 - present

SSMIS

Special Sensor Microwave Imager/Sounder

DMSP F16 - DMSP F20

Wind speedwater vaporcloud liquid water, and rain rate over oceans

2003 - present

TMI

TRMM Microwave Imager

TRMM

Sea surface temperature, wind speed, water vapor, cloud liquid water, and rain rate over oceans

1997 - 2015

AMSR-2

Advanced Microwave Scanning Radiometer-2

GCOM -W1

Sea surface temperaturewind speedwater vaporcloud liquid water, and rain rate over oceans

2012 - present

AMSR-E

Advanced Microwave Scanning Radiometer for EOS

EOS Aqua

Sea surface temperaturewind speedwater vaporcloud liquid water, and rain rate over oceans

2002 - 2011

AMSR

Advanced Microwave Scanning Radiometer

ADEOS-II

Sea surface temperaturewind speedwater vaporcloud liquid water, and rain rate over oceans

2003 – 2003

WindSat

WindSat Polarimetric Radiometer

Coriolis

Sea surface temperature, wind speed, wind direction, water vapor, cloud liquid water, rain rate, and winds through rain over oceans

2003 - present

GMI

GPM Microwave Imager

GPM

Sea surface temperaturewind speedwater vaporcloud liquid water, and rain rate over oceans

2014 - present

NSCAT

NASA Scatterometer

ADEOS-I

Wind speed and direction over oceans

1996 - 1997

SeaWinds

SeaWinds

ADEOS-II

Wind speed and direction over oceans

2003 - 2003

SeaWinds (QuikSCAT) 

SeaWinds

QuikSCAT

Wind speed and direction over oceans

1999 - 2009

ASCAT

Advanced Scatterometer

MetOp –A, MetOp – B

Wind speed and direction over oceans

2006 - present

MSU

Microwave Sounding Unit

TIROS-N, NOAA-6- to NOAA-14

Atmospheric temperatures

1978 - 2005

AMSU

Advanced Microwave Sounding Unit

NOAA-15, -16, 18, Aqua, MetOp - A

Atmospheric temperatures

1998 - present

 

4. Which data set should I use?

In order to choose the appropriate data set, start by assessing your research needs.

  • Do you need the most accurate, unprocessed data? [use daily files or orbit files if available]
  • Do you need a complete map with no data gaps? [use 3-day, weekly files, or merged data files]
  • What time frame do you need (daily, weekly, longer)?
  • Do you need precise measurements or could your result be obtained via averaged data (either in time or space)?   [use daily for precise measurements, merged data or averaged data otherwise]
  • Are you interested in data from a specific instrument or do you require a parameter measurement blended from multiple satellites?  [access instrument files or use a merged product]
  • Does your research require climate-quality, error-assessed data?  [use the monthly, 1-deg data]

Once you have determined your research needs, check out our Data Access page.

 

5. What data formats are available from Remote Sensing Systems?

The microwave products listed in the last column of the table above are available as raw binary data files (just the data, no headers, metadata or special formatting).  NetCDF files (a self-describing format with metadata) are available at NASA data archive centers.  For QuikSCAT, NSCAT, and ASCAT we provide orbital files (one orbit of data per file) as well as gridded daily, 3-day, weekly, or monthly files (orbital data mapped to a 0.25 deg grid).  Special climate summary files are also available for some geophysical parameters.  Descriptions of the data products are available on the missions or measurements web pages and included links.

Instrument Data

RSS

GHRC

PO.DAAC

 NSIDC

SSMI measurements

binary

netCDF

 

 

SSMIS measurements

binary

netCDF

 

 

TMI measurements

binary

 

 

 

AMSR-2 measurements

binary

 

 

 

AMSR-E measurements

binary

 

 

HDF-EOS

WindSat measurements

binary

 

netCDF

 

GMI measurements

binary

 

 

 

QuikSCAT winds

Binary

 

HDF

 

ASCAT winds

Binary

 

netCDF

 

NSCAT winds

Binary

 

 

 

MSU air temps

Text, UAH format, netCDF

 

 

 

AMSU air temps

Text, UAH format, netCDF

 

 

 

 

6. Where can I get Remote Sensing Systems data?

Data files are available from Remote Sensing Systems by FTP or HTTP.  See the Data Access table for specific links to the various files.  Some of the NASA data archive centers also provide the data and may offer additional visualization tools or resources.

 

7. How can I view the data before I download it?

Most data products developed at Remote Sensing Systems can be viewed using our web browse environments:  SSMI/SSMIS, TMI, AMSR-E, AMSR2, WindSatGMIQuikSCAT, and ASCAT.  The browse environment displays pre-rendered maps of data.  If you find a specific image for which you would like to download the data file, click on the Get Data button within the browse environment.

 

8. How do I read the data?

For the binary data provided by Remote Sensing Systems there are read routines in IDL, Fortan-90, Matlab, C++ and Python located in the support directories under each instrument on our FTP and HTTP data servers.  These read routines can be augmented to suit your processing needs.  Verify text files are provided to ensure proper reading of the data after altering the read routine.  Please be sure to check that the verify text file matches your output before contacting us with questions.  All read routines have been tested on Windows machines with IDL 8.2, Intel Visual Fortran-90 compiler, Matlab r2014a, Intel C++ XE 2011, and Python 2.7 on Windows machines.  NetCDF data files can also be accessed using many of the visualization tools publicly available.

 

9. I need more help.

If you have more questions, visit our Support page, where you will find FAQs and contact information.