paleoclimate

Carbonate platform evolution in response to the Mid – Pleistocene climate transition on the North-West Shelf of Australia: Insights from forward stratigraphic modelling

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Regional bathymetric map showing Scott Reef's location on Australia's Northwest Shelf relative to nearby reefs and tectonic features.

Researchers used forward stratigraphic modelling to reconstruct how Scott Reef, on Australia's Northwest Shelf, grew and changed shape during the Middle Pleistocene Transition, a period when ice age cycles became longer and more extreme. They found that a major sea-level fall around 1.2 million years ago exposed and karstified the reef, while a later long … Read more…

Coral thermal tolerances constrain extreme Mesozoic–Cenozoic hothouse reconstructions

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Maps comparing coral habitat suitability under two paleogeographic reconstructions, with fossil coral sites marked as crosses.

Modern reef-building corals only thrive within a narrow sea surface temperature range of about 22–30°C. The authors use this preference as an independent check on past climate models, running an ensemble of simulations from 250 million years ago to today across a range of CO2 levels and paleogeographies. Their coral-constrained temperature curve closely matches earlier … Read more…

DeepMIP-Eocene-p2: Experimental design for Phase 2 of the early Eocene component of the CMIP7/PMIP7 Deep-time Model Intercomparison Project (DeepMIP-Eocene)

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Maps comparing the Phase 1 (55 Ma), modern, and new Phase 2 (51 Ma) paleogeography reconstructions used in the DeepMIP-Eocene model experiments.

This paper outlines the experimental design for Phase 2 of DeepMIP-Eocene, a project that coordinates climate model simulations of the early Eocene, a period around 56–41 million years ago when global temperatures were far higher than today and carbon dioxide levels were much greater. The design updates the paleogeography, vegetation and carbon dioxide inputs used … Read more…

Tectonic and climatic implications of the Aleutian Arc initiation ≥56 million years ago

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Figure 1 from Hoernle et al. (2026)

Researchers analysed the age and chemistry of lavas from the base of the western Aleutian volcanic arc, sampled across roughly 700 kilometres, to work out when subduction began there. The results show that Aleutian subduction started at least 56 million years ago, with early lavas resembling those formed during the onset of subduction in the … Read more…

Pacific and Atlantic Modes of Overturning in the Miocene Climatic Optimum

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During the Cenozoic Era, the ocean’s meridional overturning circulation (MOC) has alternated between North Pacific and North Atlantic sinking modes. The Miocene Climatic Optimum (17.0–14.7 Ma) is a key interval for reconstructing this history because there is partial and inconclusive evidence for both MOC modes during this period. Here, we use the GFDL CM2.1 coupled climate … Read more…

Polar wander leads to large differences in past climate reconstructions

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The position of continents and oceans in geological time dictates the biogeographic dispersal of life, influences the preservation of mineral resources, and informs our understanding of Earth’s climate trajectory. Reconstructing past crustal locations requires a plate tectonic model that differs depending on whether the model uses a mantle reference frame, or a paleomagnetic reference frame, … Read more…

Earth’s ‘boring billion years’ created the conditions for complex life

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Sydney University Media Release, 20 October 2025 Plate tectonics played central role shaping life-supporting oceans Between 1.8 and 0.8 billion years ago, Earth’s tectonic activity locked atmospheric carbon dioxide into carbonate minerals within the oceanic crust, paving the way for oxygen-rich seas and evolving life. Source: research paper A study led by researchers from the … Read more…

Phanerozoic icehouse climates as the result of multiple solid-Earth cooling mechanisms

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The Phanerozoic climate has been interrupted by two long “icehouse” intervals, including the current icehouse of the last ~34 million years. While these cool intervals correspond to lower atmospheric CO2, it is unclear why CO2 levels fell, with hypotheses suggesting changes in CO2 degassing rates or modification of silicate weathering through changing continental lithology or paleogeography. Here, … Read more…

Modelling global precipitation since 250 million years ago

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We have developed a novel data-driven approach to reconstruct precipitation patterns through geological time, since the supercontinent Pangea was in existence. Our approach involves linking climate-sensitive sedimentary deposits such as coal, evaporites and glacial deposits to a global plate model, reconstructed paleo-elevation maps and high-resolution General Circulation Models via Bayesian machine learning. We model the … Read more…