multimillennial climate variation

climatology

Also known as: multimillennial variation

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Last updated

July 17, 2026

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Multimillennial climate variation refers to significant shifts in Earth's climate over thousands of years. These changes are studied using proxy evidence from natural archives like tree rings, ice cores, and ocean sediments, as direct instrumental records are limited to recent history.12

The Earth's climate has alternated between warm "greenhouse" phases and cool "icehouse" phases throughout its history. These long-term variations are driven by factors such as tectonic plate movement and changes in greenhouse gas concentrations. Orbital variations, known as Milankovitch cycles, also influence climate by altering the distribution of solar radiation over long timescales. While some regions experience cooling and increased moisture over millennia, others may become warmer and drier, reflecting complex changes in atmospheric circulation patterns.354

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climate change
Millennial and multimillennial variation
The climatic changes of the past thousand years are superimposed upon variations and trends at both millennial timescales and greater. Numerous indicators from eastern North America and Europe show trends of increased cooling and increased effective moisture during the past 3,000 years. For…
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The climatic changes of the past thousand years are superimposed upon variations and trends at both millennial timescales and greater. Numerous indicators from eastern North America and Europe show trends of increased cooling and increased effective moisture during the past 3,000 years. For…
Read More