Tabletop earth-watch stations: hooking up an antenna to a fax - to receive weather satellite data

Whole Earth Review, Fall, 1990 by Robert Horvitz

WEATHER satellites (wesats) stare down at the Earth's atmosphere, sending streams of data and pictures to stations on the ground. These pictures and data are free to anyone able to receive them. if you have a computer with a monitor that can display 16 or more levels of gray, and the proper kind of receiver, you can combine these with other accessories to set up a basic "Earth-watch" monitoring station. Wesat monitoring is already a cottage industry, with schools, farmers, commodity traders, fishermen and pilots some of the early adopters. First-rate how-to information is available at little or no cost. There is a growing number of mail-order sources for reasonably priced hardware and software. Computer bulletin boards distribute the latest orbital information, schedules, and tracking and imaging software. And the federal government supplies free support services for so-called "direct users" of NOAA weathersats.

NOAA's National Environmental Satellite, Data and Information Service (NESDIS) has excellent publications designed to help people use wesat information. Most of them are free on request. The manuals for the TIROS (polar orbit) and GOES (geosynchronous) satellites are must reading at a later stage. But the first thing to ask for is the Educator's Guide For Building and Operating Environmental Satellite Receiving Stations by R. Joe Summers (NOAA Technical Report NESDIS 44, February 1989, 106 pages softbound). Summers is a high-school science teacher in Chambersburg, PA. His manual is as useful for setting up a non-school station as it is for creating one in the classroom. To order, and request a list of other free NESDIS publications, write to:

  Ms. Mona F. Smith, E/SP21
   National Environmental Satellite, Data
   and Information Service (NESDIS), E/PO2
   Data Collection & Direct Broadcast Branch
   Room 806, World Weather Building
   Washington, DC 20233.

The American Meteorological Society recently published a thorough review of the American, Soviet, European, Indian and Japanese weathersat systems, including a survey of ways to use the data. It's pricy, but invaluable: consult it to learn what data is available where, and how to turn measurements into knowledge. Weather Satellites: Systems, Data, and Environmental Applications, edited by Rao, Holmes, Anderson, Winston and Lehr; 1990, 503 pages hardbound. $85 postpaid from the American Meteorological Society, 45 Beacon Street, Boston, MA 02108; 617/227-2425.

Another basic reference, more aimed at the public, is the Weather Satellite Handbook by Dr. Ralph E. Taggart. The 4th edition is due out about now from the American Radio Relay League (ARRL). For availability and price information, write to Metsat Products, Box 142, Mason, MI 48854.

ESPECIALLY FOR TEACHERS

There's a sudden boom in environmental education, and wesat monitoring is a great classroom tool for teaching. NASA has funded a "Direct Readout Program" to encourage teachers to use environmental satellite data in the classroom. Under this program, the Environmental Research Institute of Michigan (ERIM) is setting up a clearinghouse for curricular resources, and hosting summer workshops to teach secondary-school teachers how to build and use a wesat station. For more information, and applications for the workshop, contact Tom Leadholme at ERIM, PO. Box 8618, Ann Arbor, MI 48107; 313/994-1200, ext. 3622).

The Talcott Mountain Science Center in Connecticut is organizing an interactive weather education network. A series of live TV programs are planned for satellite relay to up to 80 schools on a biweekly schedule, with a professional meteorologist showing students how to use data that they've collected and shared, to make forecasts. For more information, contact the project coordinator, Dan Barstow, at the Talcott Center (203/677-85711.

SYSTEM SUPPLIERS

Different equipment is needed to tune in the various sources of weather imagery. There are three general options:

* Polar-orbiting satellites (regional pictures at visible and infrared wavelengths; also send data about air temperatures, ozone density and Earth radiance, plus higher-resolution pictures requiring more expensive equipment to receive).

* Wesats in geosynchronous orbit (several kinds of visual-band and infrared images, plus relays of sensor data, weather charts, schedules and announcements).

*"WEFAX" relays via shortwave (mostly drawn charts rather than pictures; aimed primarily at maritime users, so emphasizing coastal/oceanic weather).

For many people, the TIROS satellites in polar orbit are good first targets, since they combine ease of access with data that is diverse but not overwhelming in quantity. Getting the geosynchronous wesats [GOES) takes some extra gear, although that's an easy upgrade once a polar "base camp" is established.

In recent years, the trend has been for a small company to start off with a single wesat product, then to add equipment made by others to satisfy requests for help putting a complete monitoring station together. So now many companies selling system components also offer complete integrated packages. Prices vary widely, as even this partial list shows: