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    | q | 
    Based on global model simulations and for a wide range of 
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    scenarios, global
    average water vapor concentration and 
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    precipitation are projected to increase during the 21st 
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    century. 
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    | q | 
    By the second half of the 21st century, it is likely that 
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    precipitation will have increased over northern mid- to 
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    high latitudes and Antarctica in winter. 
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    | q | 
    At low latitudes there are both regional increases and 
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    decreases over land areas. 
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    | q | 
    Larger year to year variations in precipitation are very 
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    likely over most areas where an increase in mean 
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    precipitation is projected. 
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