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SMEX02 European Remote Sensing Satellite (ERS-2) AMI Data, Iowa


This data set consists of browse images acquired by the C-band Active Microwave Instrument (AMI) onboard the European Remote Sensing Satellite 2 (ERS-2) and provides only a general quality assessment of the ERS-2 AMI data. The Precision Images (PRIs) were used as a part of the Soil Moisture Experiment 2002 (SMEX02) and are available to research groups from the European Space Agency (ESA). The data were obtained over the SMEX02 study area in Iowa, USA on 31 May, 5 July, and 13 September 2002. These images are uncalibrated, subsets of the raw ERS-2 AMI PRIs. The images are a function of decibels (dB) and are intended for browsing locations and general features. They cannot be used to derive dB values; researchers interested in dB values must obtain the AMI data.

These data were collected as part of a validation study for the Advanced Microwave Scanning Radiometer - Earth Observing System (AMSR-E). AMSR-E is a mission instrument launched aboard NASA's Aqua Satellite on 04 May 2002. AMSR-E validation studies linked to SMEX are designed to evaluate the accuracy of AMSR-E soil moisture data. Specific validation objectives include assessing and refining soil moisture algorithm performance; verifying soil moisture estimation accuracy; investigating the effects of vegetation, surface temperature, topography, and soil texture on soil moisture accuracy; and determining the regions that are useful for AMSR-E soil moisture measurements.

Citing These Data

Jackson, T. and R. Van der Velde. 2004. SMEX02 European Remote Sensing Satellite (ERS-2) AMI Data, Iowa. [indicate subset used]. Boulder, Colorado USA: NASA DAAC at the National Snow and Ice Data Center.

Overview Table

Category Description
Data format JPEG image files
Spatial coverage and resolution 41.308°N to 42.389°N, -93.913°W to -93.017°W
Temporal coverage and resolution 31 May 2002 to 13 September 2002
Data were gathered on 31 May, 5 July, and 13 September 2002
File naming convention Files use the convention ERSdaacmmddyy.jpg
File size File sizes are between 4.07 MB and 4.67 MB
Parameter(s) C-band backscatter browse scenes
Procedures for obtaining data Data are available via FTP

Table of Contents

1. Contacts and Acknowledgments
2. Detailed Data Description
3. Data Access and Tools
4. Data Acquisition and Processing
5. References and Related Publications
6. Document Information

1. Contacts and Acknowledgments

Investigator(s) Name and Title

Thomas Jackson, Rogier Van der Velde
U.S. Department of Agriculture (USDA) Agriculture Research Service (ARS) National Soil Tilth Laboratory

Technical Contact

NSIDC User Services
National Snow and Ice Data Center
University of Colorado
Boulder, CO 80309-0449  USA
phone: +1 303.492.6199
fax: +1 303.492.2468
form: Contact NSIDC User Services

2. Detailed Data Description


Data are JPEG format image files.

File Naming Convention

The image files use the convention: ERSdaacmmddyy.jpg. For example, the file acquired on 7 July 2002 is "ERSdaac070502.jpg."

File Size

File sizes range from 4.07 MB to 4.67 MB.

Spatial Coverage

Southernmost Latitude: 41.308° N
Northernmost Latitude: 42.389° N
Westernmost Longitude: -93.913° W
Easternmost Longitude: -93.017° W

The spatial coverage of each scene is shown in Table 1.

Table 1. Coverage of the ERS-2 AMI scenes

datelatitude longitude latitude longitude
31 May 42.216°N 93.963°W 41.179°N 93.063°W
5 July 42.389°N 93.913°W 41.308°N 93.017°W
13 Sept42.372°N 93.935°W 41.294°N 93.041°W

Spatial Resolution

Pixel spacing is 12.5 m.

Temporal Coverage

Data were gathered on 31 May, 5 July, and 13 September 2002.

Parameter or Variable

C-band radar backscatter browse images.

Sample Data Record

The following is a small sample of the image file "ERSdaac070502.jpg."

sample PRI image

3. Data Access and Tools

Data Access

Data are available via FTP. (This data set gives only a general impression about the quality of the ERS-2 AMI data. Full ERS-2 data are available only by individual research groups from the ESA)

Table 2 below shows ordering information of the different scenes. Please contact the ESA to order the full ERS-2 AMI PRIs.

Table 2. Ordering information for the different ERS-2 scenes

date orbit frame order number Ur_id
31 May 37183 2763 33521 44018
5 July 37684 2763 34007 45335
13 Sept38686 2763 34233 45020


Total volume of combined files is 13.3 MB.

Related Data Collections

4. Data Acquisition and Processing

Sensor or Instrument Description

The C-band Active Microwave Instrument (AMI) onboard the ERS-2 space platform provides backscatter measurements around incidence angles of 23° and at VV polarization.

5. References and Related Publications

Please see the SMEX02 site for more information, and the NSIDC SMEX site to access data.

ERS Active Microwave

AMI Instrument Description

European Remote Sensing Satellite-2

6. Document Information

Acronyms and Abbreviations

The following acronyms and abbreviations are used in this document.

AMI Active Microwave Instrument
AMSR-E Advanced Microwave Scanning Radiometer - Earth Observing System
ERS-2 European Remote Sensing Satellite
ESA European Space Agency
FTP File Transfer Protocol
PRI Precision Image
SMEX Soil Moisture Experiment

Document Creation Date

June 2004

Document URL