The copper plates conducted heat rapidly to and from the bismuth telluride, thus maintaining the temperature difference.

ECONOMIST: Solar power

That warming trend was especially marked at night, when the temperature difference between the ground and the air is highest.

ENGADGET: Study says wind turbines raise surrounding area temperature, but only at night

These pens would bob 60 feet below the surface, kept in place with motors powered by heat exchangers that use the temperature difference between deep water and shallow water to generate electricity.

FORBES: Magazine Article

The operating temperature makes a difference, too.

ECONOMIST: Aircraft fatigue

When a robot finds a cave sensed by a difference in temperature it returns by the shortest route, the beeline, back to the lander.

FORBES: Swarms of Robots Could Be Used to Find Life on Mars

They get their initial power and instability from the difference in temperature between the very hot Sahara air and the substantially cooler air along the coast of the Gulf of Guinea.

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Typically, the colder it is outside the faster the warm air from inside escapes, which can leave your heating system on all through the day without any noticeable difference to the temperature.

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Things like the type of soap or the water temperature don't make as big a difference as you'd think.

WSJ: Hand-Washing Techniques for Good Health

Recently, work has shown that if you analyse long-term global temperature rise for windy days and calm days separately, there is no difference.

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Though RNA editing has been observed before, in animals ranging from humans to nematode worms, this is the first time an edit has been tied to a clear evolutionary difference caused by a feature of the environment in this case ambient temperature.

ECONOMIST: A hitherto-unknown way to evolve