Response to Marks (2025): Contemporary global warming versus climate change in the Holocene

The Holocene geological record provides the most immediate context for understanding and interpreting the climate of the present and future Earth System. Marks (2025) suggests a Holocene climate steered largely by cyclical solar forcing, and that modern warming, driven by increased solar activity, will be replaced within the coming 3 kyr by cooling almost everywhere. This view contrasts with palaeoclimate data, instrumental records, an understanding of climate drivers and feedbacks, and global and regional climate modelling studies, which show that Holocene climate was largely controlled by slow Milankovitch-related changes. Superimposed on these were minor solar fluctuations with a higher frequency. Solar activity was at the same ‘high’ level in the 1780s, 1860s and 1980s, making it a highly unlikely cause of recent warming. Modern global warming has two main drivers: 1) anthropogenic greenhouse gases, which rose steeply after 1950; and 2) both water vapour, which increases as the ocean warms, and clouds. Atmospheric CO2 levels are higher than at any other time since the Middle Miocene, making global temperatures warmer than any multi-century interval since the Last Interglacial. Earth ’s climate has left its equable Holocene state. The long residence time of CO2 ensures persistent warming for tens of millennia.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).