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Inicio de la variabilidad climática del milenio con la intensificación de la glaciación del hemisferio norte

David A Hodell¹, Fátima Abrantes^2,3, Carlos A Alvarez Zarikian⁴

¹Godwin Laboratory for Palaeoclimate Research, Department of Earth Sciences, University of Cambridge, UK.

Science (New York, N.Y.)

|February 19, 2026

Abstract:

The Quaternary Period (the last 2.58 Ma) was characterized by the waxing and waning of large ice sheets in the Northern Hemisphere. Using sediment sequences from the Iberian Margin, we demonstrate that expansion of Northern Hemisphere ice sheets around 2.7 Ma was accompanied by the emergence of millennial climate variability (MCV) during glacial periods. The onset of MCV at ~2.7 Ma was heralded by isolated precursor events, followed by multiple millennial climate oscillations at ~2.5 Ma. These events coincided with deposition of ice-rafted detritus in the North Atlantic, suggesting a role for marine-terminating ice sheets. Once established, MCV became an intrinsic feature of glacial climates of the Quaternary. Our findings underscore the profound impact Northern Hemisphere glaciation had on climate variability across multiple time scales.

Palabras clave:

variabilidad climática Cuaternario glaciación oscilaciones climáticas capas de hielo margen ibérico paleoclimatología

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