|  |  |  |  |  |  |  |  |  |  |  |  |  |  | 
   
    | q | On the 23,000-year cycle, 
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    |  | 
   
    |  | methane variations closely 
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    |  | resemble the variations of 
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    |  | monsoon strength. 
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    |  | 
   
    | q | The peak values of methane 
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    |  | match the expected peaks in 
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    |  | 
   
    |  | monsoon intensity not only in 
 | 
   
    |  | timing but also in amplitude. 
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    |  | 
   
    | q | This match suggests a close 
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    |  | connection between CH4 
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    |  | 
   
    |  | concentrations and the 
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    |  | monsoon on the 23,000-year 
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    |  | climate cycle. 
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    |  | 
   
    | q | By why? 
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