Just such an aerosol effect is believed to have disrupted the Earth's thermal balance during the Laki event, cooling some Northern Hemisphere regions by as much as 1 or more degrees Celsius below the long-term average.

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As technologies evolve that the Founders could not have possibly anticipated -- from fully automatic weapons and thermal imagers to satellites and digital technologies -- we have to figure out how to balance our rights as individuals and needs as a society.

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