Modeled Shifts in Polylepis Species Ranges in the Andes from the Last Glacial Maximum to the Present

AbstractIce cap modeling constrained by empirical studies provides an effective way of reconstructing past climates. The former Patagonian ice sheet is in a climatically significant location since it lies athwart the Southern Hemisphere westerlies and responds to the latitudinal migration of climatic belts during glacial cycles. A numerical model of the Patagonian ice cap for the last glacial maximum (LGM) is developed, which is time-dependent and driven by changing the mass balance/altitude relationship. It relies on a vertically integrated continuity model of ice mass solved over a finite difference grid. The model is relatively insensitive to ice flow parameters but highly sensitive to mass balance. The climatic input is adjusted to produce the best fit with the known limits of the ice cap at the LGM. The ice cap extends 1800 km along the Andes and has a volume of 440,000 km3. During the LGM the equilibrium line altitude (ELA) was lower than at present by at least 560 m near latitude 40°S, 160 m near latitude 50°S, and 360 m near latitude 56°S. The latitudinal variation in ELA depression can be explained by an overall fall in temperature of about 3.0°C and the northward migration of precipitation belts by about 5° latitude. Annual precipitation totals may have decreased by about 0.7 m at latitude 50°S and increased by about 0.7 m at latitude 40°S. The ELA rises steeply by up to 4 m per kilometer from west to east as the westerlies cross the Andes and this prevents ice growth to the east. The limited decrease in temperature during the LGM could be related to the modest migration of the Antarctic convergence between South America and the Antarctic Peninsula.

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Refugia of marine fish in the Northeast Atlantic during the Last Glacial Maximum: concordant assessment from archaeozoology and palaeotemperature reconstructions

Climate of the Past Discussions ◽

10.5194/cpd-6-1351-2010 ◽

2010 ◽

Vol 6 (4) ◽

pp. 1351-1389 ◽

Cited By ~ 5

Author(s):

A. J. Kettle ◽

A. Morales-Muñiz ◽

E. Roselló-Izquierdo ◽

D. Heinrich ◽

L. A. Vøllestad

Keyword(s):

Last Glacial Maximum ◽

Marine Fish ◽

Fish Species ◽

Glacial Refugia ◽

Western Mediterranean ◽

Glacial Maximum ◽

Species Ranges ◽

Last Glacial ◽

The Last Glacial Maximum ◽

The Last Glacial

Abstract. Archaeozoological finds of the remains of marine and amphihaline fish from the Last Glacial Maximum (LGM) ca. 21 ka ago show evidence of very different species ranges compared to the present. We show how an ecological niche model (ENM) based on palaeoclimatic reconstructions of sea surface temperature and bathymetry can be used to effectively predict the spatial range of marine fish during the LGM. The results indicate that the ranges of marine fish species that are now in Northwestern Europe were almost completely displaced southward from the modern distribution. Significantly, there is strong evidence that there was an invasion of fish of current economic importance into the Western Mediterranean through the Straits of Gibraltar, where they were exploited by Palaeolithic human populations. There has been much recent interest in the marine glacial refugia to understand how the ranges of the economically important fish species will be displaced with the future climate warming. Recent ENM studies have suggested that species ranges may not have been displaced far southward during the coldest conditions of the LGM. However, archaeozoological evidence and LGM ocean temperature reconstructions indicate that there were large range changes, and certain marine species were able invade the Western Mediterranean. These findings are important for ongoing studies of molecular ecology that aim to assess marine glacial refugia from the genetic structure of living populations, and they pose questions about the genetic identity of vanished marine populations during the LGM. The research presents a challenge for future archaeozoological work to verify palaeoclimatic reconstructions and delimit the glacial refugia.

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Continental/Cordilleran ice interactions: a dominant cause of westward super-elevation of the last glacial maximum continental ice limit in southwestern Alberta, Canada

CrossRef Listing of Deleted DOIs ◽

10.1080/030094801300062284 ◽

2001 ◽

Vol 30 (1) ◽

pp. 43-52 ◽

Cited By ~ 4

Author(s):

Edward C. Little ◽

Lionel E. Jackson ◽

Thomas S. James ◽

Stephen R. Hicock ◽

Elizabeth R. Leboe

Keyword(s):

Last Glacial Maximum ◽

Glacial Maximum ◽

Last Glacial ◽

The Last Glacial Maximum ◽

The Last Glacial

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Mollusk record of millennial climate variability in the Loess Plateau during the Last Glacial Maximum

Boreas ◽

10.1080/03009480210648 ◽

2002 ◽

Vol 31 (1) ◽

pp. 20-27 ◽

Cited By ~ 31

Author(s):

Naiqin Wu ◽

Tungsheng Liu ◽

Xiuping Liu ◽

Zhaoyan Gu

Keyword(s):

Climate Variability ◽

Last Glacial Maximum ◽

Loess Plateau ◽

Glacial Maximum ◽

The Loess Plateau ◽

Last Glacial ◽

The Last Glacial Maximum ◽

The Last Glacial

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Reconstructions of the past distribution of Testudo graeca mitochondrial lineages in the Middle East and Transcaucasia support multiple refugia since the Last Glacial Maximum

Herpetological Journal ◽

10.33256/31.1.1017 ◽

2021 ◽

pp. 10-17

Author(s):

Oguz Turkozan

Keyword(s):

Middle East ◽

Last Glacial Maximum ◽

Glacial Maximum ◽

Testudo Graeca ◽

Last Glacial ◽

The Past ◽

Precipitation Seasonality ◽

Multiple Refugia ◽

The Last Glacial Maximum ◽

The Last Glacial

A cycle of glacial and interglacial periods in the Quaternary caused species’ ranges to expand and contract in response to climatic and environmental changes. During interglacial periods, many species expanded their distribution ranges from refugia into higher elevations and latitudes. In the present work, we projected the responses of the five lineages of Testudo graeca in the Middle East and Transcaucasia as the climate shifted from the Last Glacial Maximum (LGM, Mid – Holocene), to the present. Under the past LGM and Mid-Holocene bioclimatic conditions, models predicted relatively more suitable habitats for some of the lineages. The most significant bioclimatic variables in predicting the present and past potential distribution of clades are the precipitation of the warmest quarter for T. g. armeniaca (95.8 %), precipitation seasonality for T. g. buxtoni (85.0 %), minimum temperature of the coldest month for T. g. ibera (75.4 %), precipitation of the coldest quarter for T. g. terrestris (34.1 %), and the mean temperature of the driest quarter for T. g. zarudyni (88.8 %). Since the LGM, we hypothesise that the ranges of lineages have either expanded (T. g. ibera), contracted (T. g. zarudnyi) or remained stable (T. g. terrestris), and for other two taxa (T. g. armeniaca and T. g. buxtoni) the pattern remains unclear. Our analysis predicts multiple refugia for Testudo during the LGM and supports previous hypotheses about high lineage richness in Anatolia resulting from secondary contact.

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