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The demise of the Laurentide ice sheet during the early Holocene epoch allows rates of ice sheet decay under natural conditions to be assessed. Analysis of terrestrial and marine records of the deglaciation along with a climate model reveal two periods of rapid melting during the final retreat of this ice sheet, with rates of sea level rise of up to 1.3 cm per year.

Tropical Pacific hydrology affects the global climate through the strength of the Pacific Walker Circulation. Yanet al. reconstruct variations in the Pacific Walker Circulation in the South China Sea over the last millennium and find that less precipitation fell during warmer and more rainfall during cool periods.

The western Pacific warm pool and the Indonesian throughflow affect tropical climate and atmospheric convection. Marine sediment records reveal uniformly elevated temperatures from 10,000 to 7,000 years ago, despite the initiation of modern Indonesian throughflow circulation about 9,500 years ago.

A build-up of warm water in the shallow tropical Atlantic during the last deglaciation and early Holocene probably resulted from intervals of weaker Atlantic Meridional Overturning Circulation, according to proxy records and model simulations.

For the past few centuries, multidecadal climate variability in North Atlantic sea surface temperatures has been modulated by the Atlantic Multidecadal Oscillation (AMO). A coral-based temperature reconstruction reveals that the AMO is a transient climate feature that only became significant after AD 1730.

The hydrological response to climate forcing during the past 25,000 years varied throughout the Indo-Pacific warm pool region. Marine sediment records suggest that during the Last Glacial Maximum, drying in northeast Borneo did not result in a vegetation shift, whereas the development of a severe dry season on Sumba led to water stress and the expansion of herby vegetation.

Analysis of benthic foraminiferal δ¹⁸O profiles from sediment cores in two depth transects in the Northwest Atlantic suggests that the subtropical gyre was deeper and stronger during the Last Glacial Maximum compared with today.

The Australian–Indonesian monsoon is an important component of the climate system in the tropical Indo-Pacific region. High-resolution records of monsoon-controlled austral winter upwelling during the past 22,000 years reveal that glacial–interglacial variations in the Australian–Indonesian winter monsoon have been in phase with the Indian summer monsoon system.

Although North Atlantic deep-water formation was greatly reduced during the last glacial maximum, bottom-water currents were as vigorous as at present. However, they were weakened during periods of North Atlantic surface freshening. A strong correlation can be seen between bottom-water-current strength and Greenland air-temperature records, thus confirming a close connection between ocean circulation and abrupt climate change.

Temperature reconstructions for the surface of the Northern Hemisphere are based largely on terrestrial records from extra-tropical or high-elevation sites, despite the fact that global average surface temperature changes closely follow those of the global tropics, which are 75 per cent ocean. Here, a decadally resolved continuous sea surface temperature is reconstructed for the Indo-Pacific warm pool that spans the past 2,000 years, allowing for comparison with observations.

Expansions of Antarctic Intermediate Water can help explain centennial-scale atmospheric CO₂ highs during the last deglaciation, according to a reconstruction of the marine carbonate system in the Southern Ocean.

The Nd isotope composition of seawater has been used to reconstruct past changes in the various contributions of different water masses to the deep ocean, with the isotope signatures of endmember water masses generally assumed to have been stable during the Quaternary. Here, the authors show that deep water produced in the North Atlantic had a significantly more radiogenic Nd signature during the Last Glacial Maximum compared to today.

Palaeoclimate records show that the Atlantic meridional overturning circulation weakened substantially at the end of the Little Ice Age, probably in response to enhanced freshwater fluxes from the Arctic and Nordic seas.

New sea surface temperature and oxygen isotope records, combined with climate modelling experiments, show that slowdowns of the Atlantic meridional overturning circulation during Heinrich stadials and the Younger Dryas stadial affected the tropical Indian Ocean hydroclimate through changes to the Hadley circulation.

Sea surface temperatures have varied over the past 2,000 years. A synthesis of surface-temperature reconstructions shows ocean surface cooling from ad 1 to 1800, with much of the trend from 800 to 1800 driven by volcanic eruptions.