Antarctic Climate Evolution

Antarctic Climate Evolution
Copyright
Contents
List of contributors
Preface
1 Antarctic Climate Evolution – second edition
	1.1 Introduction
	1.2 Structure and content of the book
	Acknowledgements
	References
2 Sixty years of coordination and support for Antarctic science – the role of SCAR
	2.1 Introduction
	2.2 Scientific value of research in Antarctica and the Southern Ocean
	2.3 The international framework in which SCAR operates
	2.4 The organisation of SCAR
	2.5 Sixty years of significant Antarctic science discoveries
	2.6 Scientific Horizon Scan
	2.7 Summary
	References
	Appendix
3 Cenozoic history of Antarctic glaciation and climate from onshore and offshore studies
	3.1 Introduction
	3.2 Long-term tectonic drivers and ice sheet evolution
	3.3 Global climate variability and direct evidence for Antarctic ice sheet variability in the Cenozoic
		3.3.1 Late Cretaceous to early Oligocene evidence of Antarctic ice sheets and climate variability
		3.3.2 The Eocene-Oligocene transition and continental-scale glaciation of Antarctica
		3.3.3 Transient glaciations of the Oligocene and Miocene
		3.3.4 Pliocene to Pleistocene
	3.4 Regional seismic stratigraphies and drill core correlations, and future priorities to reconstruct Antarctica’s Cenozoic...
		3.4.1 Ross Sea
		3.4.2 Amundsen Sea
		3.4.3 Bellingshausen Sea and Pacific coastline of Antarctic Peninsula
		3.4.4 The Northern Antarctic Peninsula and South Shetland Islands
		3.4.5 The Eastern Margin of the Antarctic Peninsula
		3.4.6 The South Orkney Microcontinent and adjacent deep-water basins
		3.4.7 East Antarctic Margin
			3.4.7.1 Weddell Sea
				3.4.7.1.1 Gondwana break-up, Weddell Sea opening and pre-ice-sheet depositional environment
				3.4.7.1.2 The Eocene-Oligocene transition and paleoenvironment during increasing glacial conditions
				3.4.7.1.3 Recent geophysical survey beneath the Ekström Ice Shelf and future directions for drilling
			3.4.7.2 Prydz Bay
				3.4.7.2.1 Early Cenozoic greenhouse and earliest glacial phase in late Eocene
				3.4.7.2.2 Oligocene–Miocene ice-sheet development
				3.4.7.2.3 The Polar Ice Sheet (late Miocene(?)–Pleistocene)
			3.4.7.3 East Antarctic Margin – Sabrina Coast
			3.4.7.4 Wilkes Land margin and Georges V Land
	3.5 Summary, future directions and challenges
	Acknowledgements
	References
4 Water masses, circulation and change in the modern Southern Ocean
	4.1 Introduction
		4.1.1 Defining the Southern Ocean
	4.2 Water masses – characteristics and distribution
		4.2.1 Upper ocean
		4.2.2 Intermediate depth waters
		4.2.3 Deep water
		4.2.4 Bottom water
	4.3 Southern Ocean circulation
		4.3.1 Antarctic Circumpolar Current (ACC)
		4.3.2 Southern Ocean meridional overturning circulation (SOMOC)
		4.3.3 Deep western boundary currents
			4.3.3.1 Pacific deep western boundary current
			4.3.3.2 Indian deep western boundary currents
			4.3.3.3 Atlantic deep western boundary current
		4.3.4 Subpolar circulation – gyres, slope and coastal currents
			4.3.4.1 Gyres
			4.3.4.2 Antarctic slope and coastal currents
	4.4 Modern Southern Ocean change
		4.4.1 Climate change
		4.4.2 Ocean change
		4.4.3 Change in dynamics and circulation
	4.5 Concluding remarks
	References
5 Advances in numerical modelling of the Antarctic ice sheet
	5.1 Introduction and aims
	5.2 Advances in ice sheet modelling
		5.2.1 Grounding line physics
		5.2.2 Adaptive grids
		5.2.3 Parallel ice sheet model – PISM
		5.2.4 Coupled models
	5.3 Model input – bed data
	5.4 Advances in knowledge of bed processes
	5.5 Model intercomparison
	5.6 Brief case studies
	5.7 Future work
	References
6 The Antarctic Continent in Gondwana: a perspective from the Ross Embayment and Potential Research Targets for Future Inve...
	6.1 Introduction
	6.2 The Antarctic plate and the present-day geological setting of the Ross Embayment
	6.3 East Antarctica
		6.3.1 The Main Geological Units during the Paleoproterozoic–Early Neoproterozoic Rodinia Assemblage
		6.3.2 From Rodinia breakup to Gondwana (c. 800–650Ma)
		6.3.3 The ‘Ross Orogen’ in the Transantarctic Mountains during the late Precambrian–early Paleozoic evolution of the paleo-...
	6.4 West Antarctic Accretionary System
		6.4.1 West Antarctica in the Precambrian to Mesozoic (c. 180Ma) evolution of Gondwana until the middle Jurassic breakup
			6.4.1.1 Precambrian to Cambrian metamorphic basement
			6.4.1.2 Devono-Carboniferous arc magmatism (‘Borchgrevink Event’) (c. 370–350Ma)
			6.4.1.3 Beacon Supergroup (Devonian-Permo-Triassic-earliest Jurassic)
			6.4.1.4 The Ellsworth-Whitmore Mountains Terrane and the Permo-Triassic arc magmatism
			6.4.1.5 Ferrar Supergroup and the Gondwana breakup (c. 180Ma)
			6.4.1.6 The Antarctic Andean Orogen
	6.5 Mesozoic to Cenozoic Tectonic Evolution of the Transantarctic Mountains
	6.6 Tectonic evolution in the Ross Sea Sector during the Cenozoic
	6.7 Concluding remarks, open problems and potential research themes for future geoscience investigations in Antarctica
		6.7.1 Persistent challenges for onshore geoscience investigations
		6.7.2 Antarctica and the Ross Orogen in the Transantarctic Mountains
		6.7.3 Antarctica after Gondwana fragmentation
	Acknowledgements
	References
7 The Eocene-Oligocene boundary climate transition: an Antarctic perspective
	7.1 Introduction
	7.2 Background
		7.2.1 Plate tectonic setting
		7.2.2 Antarctic paleotopography
		7.2.3 Paleoceanographic setting
		7.2.4 Global average and regional sea level response
		7.2.5 Proxies to reconstruct past Antarctic climatic and environmental evolution
		7.2.6 Far-field proxies
	7.3 Antarctic Sedimentary Archives
		7.3.1 Land-based outcrops
			7.3.1.1 Antarctic Peninsula Region
			7.3.1.2 King George (25 de Mayo) Island, South Shetland Islands
			7.3.1.3 The Ross Sea Region
		7.3.2 Sedimentary archives from drilling on the Antarctic Margin
			7.3.2.1 Drill cores in the western Ross Sea
			7.3.2.2 The Prydz Bay Region
			7.3.2.3 Weddell Sea
			7.3.2.4 Wilkes Land
	7.4 Summary of climate signals from Antarctic sedimentary archives
		7.4.1 Longer-term changes
		7.4.2 The climate of the Eocene-Oligocene transition
	7.5 The global context of Earth and climate system changes across the EOT
		7.5.1 Climate modelling
		7.5.2 Relative sea-level change around Antarctica
	7.6 Summary
		7.6.1 Early–middle Eocene polar warmth
		7.6.2 Late Eocene cooling
		7.6.3 Eocene-Oligocene transition
	Acknowledgements
	References
8 Antarctic Ice Sheet dynamics during the Late Oligocene and Early Miocene: climatic conundrums revisited
	8.1 Introduction
	8.2 Oligocene-Miocene Transition in Antarctic geological records and its climatic significance
	8.3 Conundrums revisited
		8.3.1 What caused major transient glaciation of Antarctica across the OMT?
		8.3.2 Apparent decoupling of Late Oligocene climate and ice volume?
	8.4 Concluding remarks
	Acknowledgements
	References
9 Antarctic environmental change and ice sheet evolution through the Miocene to Pliocene – a perspective from the Ross Sea ...
	9.1 Introduction
		9.1.1 Overview and relevance
		9.1.2 Far-field records of climate and ice sheet variability
			9.1.2.1 The Early Miocene
			9.1.2.2 The mid-Miocene
			9.1.2.3 The Late Miocene
			9.1.2.4 The Pliocene
		9.1.3 Southern Ocean Paleogeography and Paleoceanography
		9.1.4 Land elevation change and influences on Antarctic Ice Sheet evolution
	9.2 Records of Miocene to Pliocene climate and ice sheet variability from the Antarctic margin
		9.2.1 Introduction to stratigraphic records
		9.2.2 George V Land to Wilkes Land Margin
			9.2.2.1 Geological setting
			9.2.2.2 Oceanography of the Adélie coast
			9.2.2.3 Seismic stratigraphy off the George V Land to Wilkes Land Margin
			9.2.2.4 Drill core records from the George V Land to Wilkes Land Margin
			9.2.2.5 Neogene history of the George V Land to Wilkes Land margin
		9.2.3 The Ross Sea Embayment and Southern Victoria Land
			9.2.3.1 Geological setting
			9.2.3.2 Oceanography and climate in the Ross Sea Region
			9.2.3.3 Seismic stratigraphic records in the Ross Sea
			9.2.3.4 Stratigraphic records from drill cores in the Ross Sea
			9.2.3.5 Terrestrial records from Southern Victoria Land
			9.2.3.6 Neogene history in the Ross Sea Region
	9.3 Numerical modelling
		9.3.1 Miocene
		9.3.2 Pliocene
	9.4 Synthesis/summary of key climate episodes and transitions in Antarctica through the Miocene and Pliocene
		9.4.1 Early to mid-Miocene
		9.4.2 Miocene Climate Optimum
		9.4.3 Miocene Climate Transition
		9.4.4 Late Miocene
		9.4.5 Pliocene
	9.5 Next steps
	Acknowledgements
	References
10 Pleistocene Antarctic climate variability: ice sheet, ocean and climate interactions
	10.1 Background and motivation
		10.1.1 Introduction
		10.1.2 Orbital cyclicity and climate
		10.1.3 Antarctic feedbacks in the global climate system
		10.1.4 Strengths of Pleistocene research on Antarctica
	10.2 Archives of Pleistocene Antarctic climate and climate-relevant processes
		10.2.1 Polar ice cores
			10.2.1.1 Background and characteristics of ice core records
			10.2.1.2 Ice core climate proxies
			10.2.1.3 Recent advances in ice core proxies and attempts to obtain ice older than one million years
		10.2.2 Deep-sea paleoceanographic records
			10.2.2.1 Proxies for climate and ocean–atmosphere–ice sheet processes
			10.2.2.2 Pleistocene age models
			10.2.2.3 Bioturbation and resolution
			10.2.2.4 Deep-sea coral archives
		10.2.3 Ice-proximal sedimentary records
	10.3 Records of global and Southern Ocean climate during the Pleistocene
		10.3.1 Global sea level
		10.3.2 Sea surface temperatures
		10.3.3 Intermediate and deep ocean temperatures
		10.3.4 Antarctic temperatures and atmospheric CO2
		10.3.5 Sea ice extent and dust supply
	10.4 Late Pleistocene carbon cycle and climate dynamics
		10.4.1 Controls on glacial–interglacial atmospheric CO2
		10.4.2 Southern Ocean mechanisms based on sea ice, ocean circulation and deep stratification
		10.4.3 Southern Ocean mechanisms based on dust supply, productivity and nutrient utilisation
		10.4.4 Sequence of changes through the last glacial cycle
		10.4.5 Millennial climate variability and the bipolar seesaw
	10.5 Antarctic Ice Sheet dynamics in the late Pleistocene
		10.5.1 Climate context
		10.5.2 Global evidence on the Antarctic Ice Sheet
		10.5.3 Regional studies of Antarctic Ice Sheet behaviour before the LGM
		10.5.4 Regional evidence on the West Antarctic Ice Sheet
		10.5.5 Regional evidence on the East Antarctic Ice Sheet
		10.5.6 Mechanisms of Antarctic Ice Sheet retreat and insights from ice sheet modelling
		10.5.7 Millennial variability and ice sheet–ocean–climate feedbacks
	10.6 Antarctica during earlier Pleistocene climate states
		10.6.1 Lukewarm interglacials
		10.6.2 Super-interglacial MIS 31
		10.6.3 Mid-Pleistocene Transition
			10.6.3.1 Role of Antarctic Ice Sheet dynamics
			10.6.3.2 Role of the Southern Ocean carbon cycle
	10.7 Future research on Antarctica in the Pleistocene
		10.7.1 Motivation and outlook
		10.7.2 IODP Expedition 374: Ross Sea West Antarctic Ice Sheet History
		10.7.3 IODP Expedition 379: Amundsen Sea West Antarctic Ice Sheet History
		10.7.4 IODP Expedition 382: Iceberg Alley and Subantarctic Ice and Ocean Dynamics
		10.7.5 IODP Expedition 383: Dynamics of Pacific Antarctic Circumpolar Current
	Acknowledgements
	References
11 Antarctic Ice Sheet changes since the Last Glacial Maximum
	11.1 Introduction
	11.2 Response of the ice sheets to glacial climate and late Quaternary ice sheet reconstructions
	11.3 Constraining late Quaternary ice sheet extent, volume and timing
	11.4 Last interglacial (Eemian, ∼130–116ka)
	11.5 Last Glacial Maximum, subsequent deglaciation and the Holocene (∼20–0ka)
		11.5.1 Queen Maud/Enderby Land
		11.5.2 Mac.Robertson Land/Lambert Glacier-Amery Ice Shelf/Prydz Bay
		11.5.3 Princess Elizabeth Land to Wilkes Land
		11.5.4 Ross Sea sector
		11.5.5 Amundsen-Bellingshausen Seas
		11.5.6 Antarctic Peninsula
		11.5.7 Weddell Sea Embayment
	11.6 Discussion: pattern and timing of post-LGM ice retreat and thinning
	11.7 Summary
	Acknowledgements
	References
12 Past Antarctic ice sheet dynamics (PAIS) and implications for future sea-level change
	12.1 Research focus of the PAIS programme
	12.2 Importance of evolving topography, bathymetry, erosion and pinning points
	12.3 Reconstructions of Southern Ocean sea and air surface temperature gradients
	12.4 Extent of major Antarctic glaciations
	12.5 Antarctic ice sheet response to past climate warmings
	12.6 Antarctica and global teleconnections: the bipolar seesaw
	12.7 The PAIS legacy: bridging the past and the future
		12.7.1 The PAIS legacy
			12.7.1.1 Antarctic ice sheet sensitivity during past high-CO2 worlds and its contribution to global sea-level change
			12.7.1.2 Geological evidence of ocean forcing and marine ice sheet instability
			12.7.1.3 Improved temporal and spatial patterns of AIS retreat and its contribution to global Melt-Water Pulse 1A
			12.7.1.4 A better understanding of ice-sheet-ocean interactions
			12.7.1.5 Antarctic ice–Earth interactions and their influence on regional sea-level variability and Antarctic Ice Sheet dyn...
			12.7.1.6 Improved interpretation of subglacial processes from mapping seabed
			12.7.1.7 Paleo-data calibrated ice sheets models provide revised global sea-level predictions for IPCC scenarios
		12.7.2 Challenges for the next programmes
		12.7.3 Long-term projections and role of PAIS and future programs
	12.8 Coauthors from the PAIS community
	Acknowledgements
	References
	Further reading
13 The future evolution of Antarctic climate: conclusions and upcoming programmes
	13.1 Introduction: the past is key to our future
	13.2 Upcoming plans and projects
	13.3 Conclusions
	References
Index
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