Was the Laurentide Ice Sheet significantly reduced during Marine Isotope Stage 3?

Dalton, Andrew; Finkelstein, Sarah A.; Forman, Steven L.; Barnett, Peter J.; Pico, Tamara; Mitrovica, J. X.

doi:10.1130/g45335.1

Cited by 66 publications

(75 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In particular, an analysis of sediment core records from the Bohai Sea concluded that peak GMSL during MIS 3 reached −37.5 ± 7 m during mid-MIS 3 (50-37 ka), implying that ice volumes tripled from this period to the LGM (from −37.5 to −130 m GMSL) (Pico et al, 2016). Furthermore, an analysis of sea-level data on the U.S. east coast (Pico et al, 2017) supports field evidence for a substantial growth in the volume of the Laurentide Ice Sheet during MIS 3 (Carlson et al, 2018;Dalton et al, 2016Dalton et al, , 2019. On the Sunda and Sahul shelves, where modest sea-level changes cause substantial shoreline migration, these differences in peak reconstructed GMSL during MIS 3 can substantially impact retrodictions of exposed shelf area; the recently revised, higher estimates for peak GMSL would suggest more extensive inundation of continental shelves in the Indo-Pacific at mid-MIS 3.…”

Section: Recent Advances In Ice-age Sea Levelmentioning

confidence: 73%

Recent Constraints on MIS 3 Sea Level Support Role of Continental Shelf Exposure as a Control on Indo‐Pacific Hydroclimate

Pico

McGee

Russell

et al. 2020

Paleoceanog and Paleoclimatol

View full text Add to dashboard Cite

The mechanisms controlling changes in atmospheric circulation and rainfall over the Indo‐Pacific Warm Pool (IPWP) on glacial‐interglacial timescales remain a subject of considerable debate. Continental shelf exposure, through sea‐level drawdown during glacial periods, has been proposed as an important and possibly dominant control on rainfall intensity over the IPWP and Indian Ocean. However, longer records of hydroclimate change undermine this shelf exposure hypothesis. In particular, trends in some proxy records of rainfall do not track the extent of continental shelf exposure inferred from global benthic oxygen isotope records during Marine Isotope Stage 3 (MIS 3). We revisit the hypothesis that continental shelf exposure controls IPWP precipitation using the latest constraints on ice‐age sea level. Recent studies on the timing and magnitude of global mean sea level during mid‐MIS 3 (~45) suggest significantly higher peak sea level relative to previous work. Our gravitationally self‐consistent glacial isostatic adjustment sea‐level reconstructions, which adopt recent constraints on MIS 3 sea level, predict a transition from widely inundated to exposed shelves in the Indo‐Pacific region from mid‐MIS 3 to the beginning of the Last Glacial Maximum (LGM, ~19–26 ka). Over this same time period, proxy records of vegetation and hydrology from central Indonesia suggest a transition from wetter conditions during mid‐MIS 3 to drier conditions during the LGM. Our new calculations thus negate prior criticisms related to the timing and extent of shelf exposure, indicating that shelf exposure may remain an important driver for hydroclimate variability in the IPWP region on glacial‐interglacial timescales.

show abstract

Section: Recent Advances In Ice-age Sea Levelmentioning

confidence: 73%

Recent Constraints on MIS 3 Sea Level Support Role of Continental Shelf Exposure as a Control on Indo‐Pacific Hydroclimate

Pico

McGee

Russell

et al. 2020

Paleoceanog and Paleoclimatol

View full text Add to dashboard Cite

show abstract

“…The terrestrial ice sheet reconstructions before the LGM are not well constrained, especially for North American ice sheets, due to erosion during the most recent glaciation (Dalton et al, ; Kleman et al, ; Svendsen et al, ). A synthesis of geological records in the Hudson Bay Lowlands suggests that the Laurentide Ice Sheet was significantly reduced during MIS 3 and grew rapidly toward the LGM (Dalton et al, ). Terrestrial chronologies from southern Greenland during early to late Holocene show that the Greenland ice sheet margins are sensitive to not only long‐term (larger than 1,000 years) but also short‐term (less than 100 years) climate fluctuations (Reusche et al, ).…”

Section: Discussionmentioning

confidence: 99%

“…son Bay Lowlands suggests that the Laurentide Ice Sheet was significantly reduced during MIS 3 and grew rapidly toward the LGM (Dalton et al, 2019). Terrestrial chronologies from southern Greenland during early to late Holocene show that the Greenland ice sheet margins are sensitive to not only long-term (larger than 1,000 years) but also short-term (less than 100 years) climate fluctuations (Reusche et al, 2018).…”

Section: 1029/2019gl083717mentioning

confidence: 99%

Climate Noise Influences Ice Sheet Mean State

Niu

Lohmann

Gowan

2019

Geophysical Research Letters

View full text Add to dashboard Cite

Evidence from proxy records indicates that millennial‐scale abrupt climate shifts, called Dansgaard‐Oeschger events, happened during past glacial cycles. Various studies have been conducted to uncover the physical mechanism behind them, based on the assumption that climate mean state determines the variability. However, our study shows that the Dansgaard‐Oeschger events can regulate the mean state of the Northern Hemisphere ice sheets. Sensitivity experiments show that the simulated mean state is influenced by the amplitude of the climatic noise. The most likely cause of this phenomenon is the nonlinear response of the surface mass balance to temperature. It could also cause the retreat processes to be faster than the buildup processes within a glacial cycle. We propose that the climate variability hindered ice sheet development and prevented the Earth system from entering a full glacial state from Marine Isotope Stage 4 to Marine Isotope Stage 3 about 60,000 years ago.

show abstract

“…As the Laurentide Ice Sheet began its retreat toward the end of the Wisconsinan (~29,000 years before present [BP]; Dalton et al 2019), the Cisco Coregonus artedi (subgenus Leucichthys ) colonized its present range in North America from two glacial refugia, the Mississippian and Atlantic Coastal. These two lineages hybridized in massive proglacial lakes, creating secondary contacts (Figure 1; Turgeon and Bernatchez 2001a, 2001b, 2003).…”

Section: Figurementioning

confidence: 99%

Speciation in Cisco with Emphasis on Secondary Contacts, Plasticity, and Hybridization

Eshenroder

Jacobson

2020

Trans Am Fish Soc

View full text Add to dashboard Cite

The Cisco Coregonus artedi is a planktivorous fish that is widely distributed in lakes across glaciated areas of North America. With retreat of Laurentide ice, Cisco dispersed from refugia into a vast network of meltwater (proglacial) lakes that eventually receded, stranding populations in depressions-today's lakes. Refugial populations also colonized lakes that fell outside of the footprint of a proglacial lake. These two types of Cisco lakes, those inside the footprint of a proglacial lake and those outside the footprint, though uncounted, number in the high hundreds or more. All 53 lakes reported to contain sympatric forms of Cisco occur in previously inundated lakes; no sympatric forms occur in lakes that were not inundated. We reviewed Laurentide zoogeography to assess whether secondary contacts in the proglacial lakes were extensive enough to account for the distribution of sympatric lakes. We concluded that secondary contacts had been more extensive in the proglacial lakes than detected in genetic studies of Cisco. We inferred that secondary contacts in the proglacial lakes resulted in more plastic, diverse phenotypes than were found in lakes not inundated and that these phenotypes were more capable of divergence than were phenotypes inhabiting lakes not inundated. Secondary contacts in the proglacial lakes appear to have been limited to shallow-water forms of Cisco. Deepwater forms likely did not evolve until after the proglacial lakes receded, as meltwater appears to have been trophically unsuitable for pelagic fishes like Cisco. Cisco are assumed to have colonized meltwater lakes by "hopscotching" between inlets, thereby avoiding prolonged existence in meltwater. Sympatric populations of Cisco are rare in comparison with the number of allopatric populations, even in inundated lakes, indicating that divergence occurs under specialized conditions. Canalization appears to have diminished the evolvability of contemporary forms as compared to their ancestors. Hybridization within Cisco species pairs appears to be the norm and is aggravated by anthropogenically induced events.

show abstract

Was the Laurentide Ice Sheet significantly reduced during Marine Isotope Stage 3?

Cited by 66 publications

References 32 publications

Recent Constraints on MIS 3 Sea Level Support Role of Continental Shelf Exposure as a Control on Indo‐Pacific Hydroclimate

Recent Constraints on MIS 3 Sea Level Support Role of Continental Shelf Exposure as a Control on Indo‐Pacific Hydroclimate

Climate Noise Influences Ice Sheet Mean State

Speciation in Cisco with Emphasis on Secondary Contacts, Plasticity, and Hybridization

Contact Info

Product

Resources

About