Satellite and weather balloon data tell us that the Earth's average temperature has fallen slightly during the last 20 years.

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But a week later this was retracted, and another release was written, saying that the debris was simply that of a military weather balloon.

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The markings have been blamed variously on mice, on a weather balloon trailing lines and tackle, and most amusingly on a kangaroo that may have escaped from a local zoo.

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Or eavesdrop as producer Melissa Bernstein recalls the wild story of attaching a camera to a weather balloon only to have it break loose and fly 200 miles before landing largely intact.

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The boy's father, Richard Heene, apparently used the balloon to track the weather.

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Hurtling towards the stratosphere the balloon was fitted with weather instruments designed to measure, among other things, temperature, pressure and wind speed.

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Unstable means that if an imaginary balloon filled with air from near the ground were to be lifted upward, colliding with some weather feature such as a cold front, the "balloon" would become warmer than the surrounding air at that level.

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Weather stations, ocean measurements, decreases in snow cover, reductions in Arctic sea ice, longer growing seasons, balloon measurements, boreholes and satellites all show results consistent with the surface record of warming.

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