Sandy Loess Records of Precipitation Changes and Monsoon Migrations in the Hunshandake Sandy Land Since the Last Glacial Maximum

Abstract The zonal and annual mean tropical precipitation response to paleoclimate and anthropogenic forcing scenarios ranging from the Last Glacial Maximum (LGM), CO2 quadrupling (4XCO2 ), mid-Holocene, North Atlantic freshwater hosing and volcanic forcing is analyzed in an ensemble of global climate models. Zonally averaged tropical precipitation changes are characterized in terms of three geometric manipulations of the climatological precipitation (hereafter, modes): meridional shifts, intensifications, and meridional contractions. We employ an optimization procedure that quantifies the magnitude and robustness (across different models) of changes in each mode in response to each forcing type. Additionally, the fraction of precipitation changes that are explained by the modes (in isolation and combined) is quantified. Shifts are generally less than 1º latitude in magnitude and explain a small fraction (<10%) of tropical precipitation changes. Contractions and intensifications are strongly anti-correlated across all simulations with a robust intensification and contraction of precipitation under global warming and a robust reduction and expansion under global cooling during the Last Glacial Maximum. The near constant scaling between contractions and intensifications across all simulations is used to define a joint contraction/intensification (CI) mode of tropical precipitation. The CI mode explains nearly 50% of the precipitation change under 4XCO2 and LGM forcing by optimizing a single parameter. These results suggest the shifting mode that has been extensively used to interpret paleo-rainfall reconstructions is of limited use for characterizing forced zonal mean precipitation changes and advocates for a reinterpretation of past precipitation changes to account for the CI mode

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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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