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An image satellite weather folks check.How do we interpret satellite imagery? To use the pictures from the image satellite weather specialists need to process and customize the information.
For example, see a sample satellite image for Calgary, Alberta Canada. We can derive planet temperatures, humidity pictures, cloud pics and wind data from the satellite depictions. Both for identifying long-term trends and providing the greater precision needed for short-term weather predictions, sometimes called nowcasting. Satellite pix offer us enhanced perspective for use in air pollution studies as well. Large scale image satellite weather photography has become important to pilots flying into areas with a sparse surface weather data. We can extract the information they need from a series of photographs. Weather satellite historyThe first weather satellite: Tiros-1 (1 tiros) in 1960, USA.Since then we have become used to a That was brief. Are you in the satellite business? - Selling satellite receivers and signals? Imagery? Sell your stuff online. It can be easier. This is how I made this busy web site. Geostationary?A satellite can be launched to a perfect combination of acceleration, speed, velocity and height so that its position above a particular spot on the rotating earth never changes. That's what geostationary means.
It has to be over the equator for this to work. Since it is so high ( around 22,000 miles or 36,000 km ), it can give us a good equator map and cloud pictures over most of the earth, except for the poles. It has to go nearly 7000 miles or 11,000 km per hour relative to the earth's axis to stay positioned.
Portable weather stations, kind of…We receive a fresh image satellite weather snapshot of varying energy-frequency-wavelength values for a large area of the planet every 15 minutes. These are quite good for animating satellite photos. Five satellites allow us to see the entire earth between around 60°N and 60°S. They linger above the equator at 75°W, 135°W, 140°E, 70°E and about 0°, the prime meridian. What's even better, if one fails, the others can reposition themselves to compensate for the shortfall until it starts working again.The vehicles, at nearly half a ton each, rotate rapidly for stability while the cameras are held steady and they get useful solar energy from various sunlight wavelengths. Clever thinking on the part of these engineers. The satellite instruments provide photos using infrared radiation and visible light, plus a collection of other data. A telescope scans the earth to give us illustrations with the required resolution and then sends the data to the ground where computers overlay the continent geography maps. The completed image then goes back to the satellite for worldwide distribution to forecast centres, tv stations and whatnot. Though it's not flawless, the whole system is quite dependable. Sweeping the earth below…We have to make a trade-off here. High altitude weather satellites can see larger areas, anytime, but with a comparatively low resolution. Lower satellites can see much closer and clearer, but not very far and so they have to move across the earth to get a complete image satellite weather picture.Only 500 miles/800 km up or so, we have polar orbiting satellites, This is fast enough so that each satellite's orbit remains fixed relative to the sun and it always makes its northbound journey near noon and each place gets its photo taken at roughly the same time every day. We call this time coordinated quality sun-synchronous. Visualize the satellite photos resembling ribbons stretching up and down around the earth. Naturally, there will be increasing overlap closer to the poles. The extra data in these regions are used for making more complete North Pole maps. This increased temporal resolution, frequency, gives high-latitude meteorologists good North Pole pictures and usable animations. That's very important to these people because of the poorer image satellite weather photo quality from the geo-stationary satellites in these Polar Regions. This so-called Television Infra-Red Observational Satellite (TIROS) comes complete with cameras and other high-tech image satellite weather devices such as radiometers, sounders, data collection systems and monitors. Receivers that can "see" the satellite can get data from it and the High Resolution Picture Transmission (HRPT) images can be quite amazing.
The big picture comparisonThese two types of satellites provide us with at variety of angles for interpreting the imagary and making sense of the chaos.Geostationary - Steady, high frequency image satellite weather pictures and large area photographs. Good for animated satellite displays. Polar Orbiting - Greater image satellite weather resolution for studying and analyzing photos, but not for animating them. This one's also less costly.
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