Project Description

DMSP SSM/I Brightness Temperatures
for Polar Regions

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Summary

The Special Sensor Microwave/Imager was built in support of the Navy's Fleet Numerical Oceanography Command (FNOC) and the Air Force Weather Center. Operating continuously, it advanced viewing capacities over those of earlier microwave instruments, such as the Nimbus-7 SMMR, in areas such as swath width and calibrating precision. Its mission is to provide global, visual and infrared cloud data and other specialized near-real-time meteorological, oceanographic and solar-geophysical data for use in weather analyses and defense operations.

Table of Contents

1. Project Overview
2. Data Availability
3. Access
4. Principal Investigator
5. Submitting Investigator
6. References
7. Detailed Description

1.Project Overview

Name of Project

Special Sensor Microwave/Imager (SSM/I)

Purpose

SSM/I brightness temperatures are used in many practical applications, such as for tracking global rainfall and storm systems, and measuring ocean surface wind speeds and sea states. As they relate to the Polar Regions, brightness temperatures are used to derive, measure, track and map sea ice concentration and age.

Geographic Region

The sensor samples every 12.5 km along track at 85.5 GHz, every 25.0 km along track at lower frequencies. Coverage is global except for circular sectors, 311 km in radius located poleward of 87.2 degrees North and 87 degrees South, which are never measured due to orbit inclination. The measurement footprint size (effective field of view) is as follows:

• 19.3 GHz 70 X 45 km
• 22.2 GHz 60 X 40 km
• 37.0 GHz 38 X 30 km
• 85.5 GHz 16 X 14 km

The brightness temperatures contained in this data set are gridded to the polar stereographic projection. Please see Grid Definition Methodology for a complete description of the geographic regions described in this data collection.

2. Data Availability

Data Type

Displayed in polar stereographic projection, gridded brightness temperatures for North and South polar regions are contained on 18 CD-ROM volumes, each covering about three months of data recorded from 9 July 1987 through 31 December 1991.

3. Access

NSIDC User Services
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, CO 80309-0449  USA
phone: +1 303.492.6199
fax: +1 303.492.2468
form: Contact NSIDC User Services
e-mail: nsidc@nsidc.org

4. Principal Investigator

Roger Barry

Please direct all queries to NSIDC User Services.

5. Submitting Investigator

Vince Troisi

Please direct all queries to NSIDC User Services.

6. References

Please see the bibliography.

7. Detailed Description

Please review the DMSP SSM/I Brightness Temperatures for Polar Regions data set documentation.

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Document Type: Project Document
Revision Date: December 1995