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Earth photo satellite chaos: figure out what you see.

Suppose you just saw an earth photo satellite image for the first time. How do you make sense of the mess of light and dark areas, the monotony and the dull shades of grey? Or moving patches of grey in a live photo satellite animation? If you could increase the contrast in the photo, things would become more distinct.

I can see clearly now

Our eyes can only separate around 40 shades of grey.

The satellite system uses over 200, most of which mark divisions meteorologists do not really care about at any given time.

Forecasters often use an infra-red satellite display. This maps a distinct grey shade to a small temperature range, and color may be added for clarity.

The image becomes more useful if a limited number of shades pinpoints important items as sharply as possible. The extra tones at hand allow us to work in other temperature ranges.

Fortunately, users of this earth photo satellite product can customize it to their needs if equipped with the right software. A computer program allows you to assign a specific brightness to a narrow temperature range or radiation intensity value. Scientists call this type of control image enhancement, and we can compare it to the gamma correction example in the photos above.

Enhance your own image by going online...maybe by
developing a web site of your own.

An example, please.

Need help with this? How useful is a black to white scale that uses evenly divided temperature/grey increments ranging from less than minus 150°F to over 130°F?

These extremes may be seen occasionally in the earth-atmosphere system. But we don't witness them often, and certainly not within a small geographical region at any given time.

Now suppose you were a meteorologist for an area who expects, at this time of year, to see temperatures always between 10° and 80°. Why not set those 40 or so levels to cover that temperature range and stow away the un-needed temperature increments into a small range of greys?

Now you have a custom enhanced earth photo satellite image that suits the needs of your current situation. It addresses your relevant temperature span.

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Advanced techniques

Another trick the software allows you to use is to cycle through the entire grey-scale twice in one earth photo satellite illustration.

We find this very useful where good detail is needed over a tremendous temperature (which corresponds to elevation) range, such as in a thunderstorm cloud, a cumulonimbus.

Even more modern technology allows us to use various colours instead of just greys. Furthermore, you can overlay different types of earth photo satellite images and get a multispectural composite. Expect great developments in this area of satellite interpretations in the future.

A scale of shades or colors on the side of the image shows the viewer level what temperature range each shade corresponds to. And with it you can identify the extremes and convert brilliance level to temperature.