The extent of the [[sea ice]] in the [[Atlantic]] sector of the [[Arctic Ocean|Arctic sea]] has been shown to be correlated with the length of the [[sunspot cycle]] during the last 450 years. [http://www.tmgnow.com/repository/solar/lassen1.html]
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The extent of the [[sea ice]] in the [[Atlantic]] sector of the [[Arctic Ocean|Arctic sea]] has been shown to be correlated with the length of the [[sunspot cycle]] during the last 450 years.<ref>http://www.tmgnow.com/repository/solar/lassen1.html</ref>