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Special Feature: Studying the Oceans from Space

IP.com Disclosure Number: IPCOM000131348D
Original Publication Date: 1978-Aug-01
Included in the Prior Art Database: 2005-Nov-10
Document File: 11 page(s) / 43K

Publishing Venue

Software Patent Institute

Related People

Ware Myers: AUTHOR [+3]

Abstract

[Figure containing following caption omitted: Three high-speed data streams from a new ocean- monitoring satellite are computer-processed on the ground into meaningful geophysical and meteorological information.] On June 26, 1978, a NASA Jet Propulsion Laboratory satellite, Seasat-A, was launched into a near-polar orbit from Vandenberg Air Force Base, California. It is orbiting earth 14 times a day at the average equatorial altitude of 784 kilometers (about 500 miles). Sweeping across 95 percent of the ocean area every 36 hours, it is capable of taking more measurements in a single day than previous sea-based instruments acquired in decades.

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THIS DOCUMENT IS AN APPROXIMATE REPRESENTATION OF THE ORIGINAL.

This record contains textual material that is copyright ©; 1978 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Contact the IEEE Computer Society http://www.computer.org/ (714-821-8380) for copies of the complete work that was the source of this textual material and for all use beyond that as a record from the SPI Database.

Special Feature: Studying the Oceans from Space

Ware Myers

Contributing Editor

(Image Omitted: Three high-speed data streams from a new ocean- monitoring satellite are computer-processed on the ground into meaningful geophysical and meteorological information.)

On June 26, 1978, a NASA Jet Propulsion Laboratory satellite, Seasat-A, was launched into a near-polar orbit from Vandenberg Air Force Base, California. It is orbiting earth 14 times a day at the average equatorial altitude of 784 kilometers (about 500 miles). Sweeping across 95 percent of the ocean area every 36 hours, it is capable of taking more measurements in a single day than previous sea-based instruments acquired in decades.

The satellite's four microwave instruments and its visual and infrared radiometer are returning data to earth in three streams: an occasional realtime analog transmission from the synthetic aperture radar at 20 MHz, a rate equivalent to 110 million bits per second; a real-time digital transmission from the other instruments at 25K bps; and a periodic digital transmission of stored data at 800K bps.

Because of the great expanse of the sea, little is known on a daily basis of sea-surface winds and temperatures, wave heights and lengths, and storms and ice fields. For example, almost all the information about sea waves comes from about 1200 ships -- most of them in the northern hemisphere -- that occasionally report estimates of wave height, period, and dominant direction. However, when oceanographers have had the opportunity to compare these estimates with actual measurements, they have often found them inaccurate.

Yet this type of data is needed -- and needed with about the same frequency and density as now required for meteorological data over land in the United States -- if meteorologists are to achieve accurate one- or two-week forecasts." Moreover, the lack of data from the oceans has made long-range forecasts for the continents themselves much less accurate than they might be.

   (Image Omitted: Studying the world's oceans -- Painting shows Seasat A spacecraft as it studies oceans from earth orbit. The spacecraft is determining if microwave sensors have value in providing information about sea state and related weather phenomena. Seasat A was launched from Vandenberg Air Force Base on June 26, 1978, into a near polar orbit 800 kilometers (500 miles) high. It circles the globe 14 times a day, providing coverage of 95 percent of the oceans every 36 hours. Instrument resolution varies, but in some cases it is as small as 25 mete...