Featured
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Glacial cooling and climate sensitivity revisited
A compilation of proxy data are used with an isotope-enabled climate model ensemble to constrain cooling during the Last Glacial Maximum, producing estimates of equilibrium climate sensitivity that agree well with the current consensus range.
- Jessica E. Tierney
- , Jiang Zhu
- & Christopher J. Poulsen
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Article |
Ice retreat in Wilkes Basin of East Antarctica during a warm interglacial
Uranium isotopes in subglacial precipitates from the Wilkes Basin of the East Antarctic Ice Sheet reveal ice retreat during a warm Pleistocene interglacial period about 400,000 years ago.
- T. Blackburn
- , G. H. Edwards
- & J. T. Babbe
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Article |
The timing and effect of the earliest human arrivals in North America
A Bayesian age model suggests that human dispersal to the Americas probably began before the Last Glacial Maximum, overlapping with the last dates of appearance for several faunal genera.
- Lorena Becerra-Valdivia
- & Thomas Higham
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Article |
Millennial-scale hydroclimate control of tropical soil carbon storage
Over the past 18,000 years, the residence time and amount of soil carbon stored in the Ganges–Brahmaputra basin have been controlled by the intensity of Indian Summer Monsoon rainfall, with greater carbon destabilization during wetter, warmer conditions.
- Christopher J. Hein
- , Muhammed Usman
- & Valier V. Galy
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Article |
Temperate rainforests near the South Pole during peak Cretaceous warmth
Multi-proxy core data and model simulations support the presence of temperate rainforests near the South Pole during mid-Cretaceous warmth, indicating very high CO2 levels and the absence of Antarctic ice.
- Johann P. Klages
- , Ulrich Salzmann
- & M. Scheinert
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Article |
Coupling of Indo-Pacific climate variability over the last millennium
Coral records indicate that the variability of the Indian Ocean Dipole over the last millennium is strongly coupled to variability in the El Niño/Southern Oscillation and that recent extremes are unusual but not unprecedented.
- Nerilie J. Abram
- , Nicky M. Wright
- & David Heslop
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Article |
Oceanic forcing of penultimate deglacial and last interglacial sea-level rise
A reduction in the strength of the Atlantic Meridional Overturning Circulation initiated during the penultimate deglaciation led to excess polar ice losses, contributing to higher sea levels during the last interglacial period.
- Peter U. Clark
- , Feng He
- & Sarah Dendy
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Article |
Palaeoclimate evidence of vulnerable permafrost during times of low sea ice
A reconstruction of permafrost dynamics using speleothems from a Siberian cave indicates that Siberian permafrost is robust to warming when Arctic sea ice is present, but vulnerable when it is absent.
- A. Vaks
- , A. J. Mason
- & G. M. Henderson
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Article |
Two-million-year-old snapshots of atmospheric gases from Antarctic ice
Analysis of two-million-year-old ice from Antarctica provides a direct comparison of atmospheric gas levels before and after the shift from glacial cycles of 100 thousand years to 40-thousand-year cycles around one million years ago.
- Yuzhen Yan
- , Michael L. Bender
- & John A. Higgins
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Letter |
The amplitude and origin of sea-level variability during the Pliocene epoch
Sea level varied by 13 ± 5 metres on average, but up to 25 metres, over glacial–interglacial cycles during the Pliocene epoch, due to partial collapses of Antarctic Ice Sheets.
- G. R. Grant
- , T. R. Naish
- & M. O. Patterson
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Letter |
Mediterranean winter rainfall in phase with African monsoons during the past 1.36 million years
Comparisons between past regional drivers of precipitation extremes found time series data from Lake Ohrid and modern climate models of the Mediterranean may help to reduce simulation uncertainties in predictions of the Mediterranean climate.
- Bernd Wagner
- , Hendrik Vogel
- & Xiaosen Zhang
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Letter |
No evidence for globally coherent warm and cold periods over the preindustrial Common Era
Warm and cold periods over the past 2,000 years have not occurred at the same time in all geographical locations, with the exception of the twentieth century, during which warming has occurred almost everywhere.
- Raphael Neukom
- , Nathan Steiger
- & Johannes P. Werner
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Letter |
Neogene cooling driven by land surface reactivity rather than increased weathering fluxes
A carbon cycle model constrained by weathering-sensitive isotopic tracers reveals that long-term cooling in the Neogene period reflects a change in how surface denudation is partitioned into weathering and erosion.
- Jeremy K. Caves Rugenstein
- , Daniel E. Ibarra
- & Friedhelm von Blanckenburg
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Letter |
Isotopic constraint on the twentieth-century increase in tropospheric ozone
Isotope data from polar firn and ice are used to constrain the increase in tropospheric ozone between 1850 and 2005 ad.
- Laurence Y. Yeung
- , Lee. T. Murray
- & Jérôme Chappellaz
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Letter |
Industrial-era decline in subarctic Atlantic productivity
A continuous, multi-century record of subarctic Atlantic marine productivity shows that a marked decline in net primary productivity has occurred across the subarctic Atlantic basin over the past two centuries.
- Matthew B. Osman
- , Sarah B. Das
- & Eric S. Saltzman
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Article |
Twentieth-century hydroclimate changes consistent with human influence
Multiple observational datasets and reconstructions using data from tree rings confirm that human activities were probably affecting the worldwide risk of droughts as early as at the beginning of the twentieth century.
- Kate Marvel
- , Benjamin I. Cook
- & A. Park Williams
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Letter |
Mid-latitude net precipitation decreased with Arctic warming during the Holocene
A reduced gradient in temperatures between low and high latitudes during the Holocene led to drier mid-latitudes.
- Cody C. Routson
- , Nicholas P. McKay
- & Toby Ault
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Letter |
Nonlinear rise in Greenland runoff in response to post-industrial Arctic warming
Ice-core-derived melt records reveal that atmospheric warming has recently intensified Greenland ice-sheet surface melt and runoff to levels that are exceptional over at least the last 350 years.
- Luke D. Trusel
- , Sarah B. Das
- & Michiel R. van den Broeke
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Letter |
Abrupt ice-age shifts in southern westerly winds and Antarctic climate forced from the north
The position of the Southern Hemisphere westerly winds responds immediately to abrupt North Atlantic climate events of the last ice age, with a spatially heterogeneous impact on Antarctic climate.
- Christo Buizert
- , Michael Sigl
- & Eric J. Steig
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Letter |
Ice loss from the East Antarctic Ice Sheet during late Pleistocene interglacials
Studies of an Antarctic marine sediment core suggest that the East Antarctic Ice Sheet retreated in the vicinity of the Wilkes Subglacial Basin during extended warm periods of the late Pleistocene, when temperatures were similar to those predicted to occur within this century.
- David J. Wilson
- , Rachel A. Bertram
- & Carlota Escutia
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Letter |
Rapid glaciation and a two-step sea level plunge into the Last Glacial Maximum
Details of the drops in sea level associated with glaciation during the Last Glacial Maximum are revealed using a coral proxy from the Great Barrier Reef.
- Yusuke Yokoyama
- , Tezer M. Esat
- & Hironobu Kan
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Letter |
North Pacific freshwater events linked to changes in glacial ocean circulation
Sediment-core and modelling analyses suggest that, during distinct cold periods known as Heinrich Stadials, changes in ocean circulation in the North Atlantic triggered discharge of freshwater from the Cordilleran Ice Sheet into the North Pacific.
- E. Maier
- , X. Zhang
- & G. Lohmann
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Letter |
A two-million-year-long hydroclimatic context for hominin evolution in southeastern Africa
A multiple-proxy reconstruction for the catchment of the Limpopo River and of sea surface temperatures in the Indian Ocean provides evidence for hydroclimatic changes that may have been important in hominin evolution.
- Thibaut Caley
- , Thomas Extier
- & Jacques Giraudeau
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Letter |
Synchronous tropical and polar temperature evolution in the Eocene
A 26-million-year record of equatorial sea surface temperatures reveals synchronous changes of tropical and polar temperatures during the Eocene epoch forced by variations in concentrations of atmospheric carbon dioxide, with a constant degree of polar amplification.
- Margot J. Cramwinckel
- , Matthew Huber
- & Appy Sluijs
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Review Article |
Antarctic and global climate history viewed from ice cores
A discussion of past Antarctic and global climate history as seen from Antarctic ice cores, with an outlook on future goals and drilling priorities.
- Edward J. Brook
- & Christo Buizert
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Letter |
Minimal East Antarctic Ice Sheet retreat onto land during the past eight million years
Analysis of cosmogenic isotopes from a marine sediment core shows that much of the land-based East Antarctic Ice Sheet has remained stable for the past eight million years, including during the warm Pliocene epoch.
- Jeremy D. Shakun
- , Lee B. Corbett
- & Carling C. Hay
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Letter |
Anomalously weak Labrador Sea convection and Atlantic overturning during the past 150 years
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.
- David J. R. Thornalley
- , Delia W. Oppo
- & Lloyd D. Keigwin
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Letter |
Climatic control of Mississippi River flood hazard amplified by river engineering
A suite of river discharge, tree-ring, sedimentary and climate data shows that the Mississippi’s flood magnitude has risen by about twenty per cent over the past half-century, largely owing to engineering works.
- Samuel E. Munoz
- , Liviu Giosan
- & Jeffrey P. Donnelly
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Letter |
Global patterns of declining temperature variability from the Last Glacial Maximum to the Holocene
Temperature variability decreased globally by a factor of four between the Last Glacial Maximum and the Holocene epoch, as a result of changes in the meridional temperature gradient.
- Kira Rehfeld
- , Thomas Münch
- & Thomas Laepple
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Letter |
Southern Hemisphere climate variability forced by Northern Hemisphere ice-sheet topography
An Antarctic ice core reveals that, during the last ice age, the topography of Northern Hemisphere ice sheets shifted tropical Pacific convection eastward, increasing climate variability in the high southern latitudes.
- T. R. Jones
- , W. H. G. Roberts
- & J. W. C. White
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Letter |
Reconciling divergent trends and millennial variations in Holocene temperatures
Analysis of pollen records from North America and Europe reveals a warming trend over the Holocene, consistent with climate-model simulations.
- Jeremiah Marsicek
- , Bryan N. Shuman
- & Simon Brewer
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Letter |
Initiation and long-term instability of the East Antarctic Ice Sheet
Geophysical and geological data reveal increased ice-sheet variability and surface meltwater—possibly analogous to future conditions—offshore of the Aurora subglacial basin of East Antarctica during warm climate intervals of the past 50 million years.
- Sean P. S. Gulick
- , Amelia E. Shevenell
- & Donald D. Blankenship
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Letter |
Evidence of marine ice-cliff instability in Pine Island Bay from iceberg-keel plough marks
Plough marks in Pine Island Bay, West Antarctica, left by the keels of drifting icebergs 12,000 years ago provide evidence that marine ice-cliff instability can drive rapid ice-sheet retreat.
- Matthew G. Wise
- , Julian A. Dowdeswell
- & Robert D. Larter
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Letter |
Very large release of mostly volcanic carbon during the Palaeocene–Eocene Thermal Maximum
Boron and carbon isotope data, used in an Earth system model, show that the Palaeocene–Eocene Thermal Maximum was associated with a much greater release of carbon than thought, most probably triggered by volcanism in the North Atlantic.
- Marcus Gutjahr
- , Andy Ridgwell
- & Gavin L. Foster
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Letter |
Minimal geological methane emissions during the Younger Dryas–Preboreal abrupt warming event
Measurements from Antarctic ice suggest that geological methane emissions are much lower than previously thought, and that methane emissions from hydrates and permafrost in response to climate warming are minimal.
- Vasilii V. Petrenko
- , Andrew M. Smith
- & Jeffrey P. Severinghaus
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Brief Communications Arising |
Overestimate of committed warming
- Gavin A. Schmidt
- , Jeff Severinghaus
- & Thomas F. Stocker
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Letter |
Isotopic evidence of multiple controls on atmospheric oxidants over climate transitions
Observations from a Greenland ice core reveal that tropospheric oxidants are sensitive to climate-driven changes in reactive halogen chemistry and stratosphere-to-troposphere transport of ozone, in addition to ozone precursor emissions.
- Lei Geng
- , Lee T. Murray
- & Becky Alexander
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Article |
A simple rule to determine which insolation cycles lead to interglacials
A simple model, based on only summer insolation energy and time since the previous deglaciation, correctly predicts the deglaciation history of the past 2.6 million years, including the change in frequency of glacial–interglacial cycles about one million years ago.
- P. C. Tzedakis
- , M. Crucifix
- & E. W. Wolff
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Letter |
Theory of chaotic orbital variations confirmed by Cretaceous geological evidence
Cretaceous astrochronologic evidence reveals a resonance transition associated with the orbits of Mars and the Earth, confirming predicted chaotic Solar System behaviour and enabling an improvement in the geological timescale.
- Chao Ma
- , Stephen R. Meyers
- & Bradley B. Sageman
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Letter |
Heinrich events triggered by ocean forcing and modulated by isostatic adjustment
Heinrich events — episodes of massive iceberg discharge from the Laurentide Ice Sheet into the North Atlantic Ocean — are triggered by the incursion of warm ocean waters destabilizing the calving front.
- Jeremy N. Bassis
- , Sierra V. Petersen
- & L. Mac Cathles
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Letter |
Hydroclimate changes across the Amazon lowlands over the past 45,000 years
Oxygen isotope records derived from stalagmites in the eastern Amazon reveal that rainfall was about half of today’s during the Last Glacial Maximum but half again as much during the mid-Holocene, broadly coinciding with global changes in temperature and carbon dioxide.
- Xianfeng Wang
- , R. Lawrence Edwards
- & Hong-Wei Chiang
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Letter |
Centennial-scale Holocene climate variations amplified by Antarctic Ice Sheet discharge
Records of iceberg-rafted debris and climate model simulations reveal that fluctuations in Antarctic Ice Sheet discharge may have amplified climate fluctuations during the Holocene.
- Pepijn Bakker
- , Peter U. Clark
- & Michael E. Weber
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Letter |
Greenland was nearly ice-free for extended periods during the Pleistocene
Measurements of cosmic-ray-produced 10Be and 26Al in a bedrock core from beneath the summit of the Greenland Ice Sheet show that Greenland was nearly ice-free for extended periods under Pleistocene climate forcing.
- Joerg M. Schaefer
- , Robert C. Finkel
- & Roseanne Schwartz
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Letter |
A persistent and dynamic East Greenland Ice Sheet over the past 7.5 million years
10Be and 26Al isotopic evidence in quartz sand from the seafloor shows that a dynamic East Greenland Ice Sheet has existed for the past 7.5 million years.
- Paul R. Bierman
- , Jeremy D. Shakun
- & Dylan H. Rood
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Letter |
Sub-ice-shelf sediments record history of twentieth-century retreat of Pine Island Glacier
Many glaciers and ice shelves in the West Antarctic Ice Sheet are retreating or thinning rapidly, but the triggering mechanism has been unclear; now, the retreat of Pine Island Glacier is found to have begun in the 1940s following warming El Niño events in the Pacific Ocean, showing that glacial retreat can continue long after an initial push from the climate.
- J. A. Smith
- , T. J. Andersen
- & D. G. Vaughan
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Letter |
Evolution of global temperature over the past two million years
Reconstruction of global average surface temperature for the past two million years shows continuous cooling until about 1.2 million years ago, followed by a general flattening, with close coupling of global temperature and atmospheric greenhouse gas concentrations over the past 800,000 years.
- Carolyn W. Snyder
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Letter |
Late Pleistocene climate drivers of early human migration
The dispersal of Homo sapiens across the Arabian Peninsula and the Levant during the last glacial period was not a single event, but occurred in four astronomically-paced migration waves.
- Axel Timmermann
- & Tobias Friedrich
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Article |
Early onset of industrial-era warming across the oceans and continents
Reconstructions of ocean and land temperatures since ad 1500 indicate that sustained, industrial-era warming of land areas in the Northern Hemisphere and tropical oceans began earlier than previously thought, around the mid-nineteenth century.
- Nerilie J. Abram
- , Helen V. McGregor
- & Lucien von Gunten