A high-resolution record of Holocene environmental and climatic changes from Lake Balikun (Xinjiang, China): Implications for central Asia

This paper presents radiocarbon results from a single Diploastrea heliopora coral from Vanuatu that lived during the Younger Dryas climatic episode, between ca. 11,700 and 12,400 calendar yr bp. The specimen has been independently dated with multiple 230Th measurements to permit calibration of the 14C time scale. Growth bands in the coral were used to identify individual years of growth. 14C measurements were made on each year. These values were averaged to achieve decadal resolution for the 14C calibration. The relative uncertainty of the decadal 14C data was below 1% (2σ). The data are in good agreement with the existing dendrochronology and allow for high-resolution calibration for most years. Variations in the fine structure of the 14C time series preserved in this specimen demonstrate sporadic rapid increases in the Δ14C content of the surface ocean and atmosphere. Certain sharp rises in Δ14C are coincident with gaps in coral growth evidenced by several hiatuses. These may be related to rapid climatic changes that occurred during the Younger Dryas. This is the first coral calibration with decadal resolution and the only such data set to extend beyond the dendrochronology-based 14C calibration.

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Analysis on impacts of hydro-climatic changes and human activities on available water changes in Central Asia

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.139779 ◽

2020 ◽

Vol 737 ◽

pp. 139779

Author(s):

Hui Chen ◽

Hailong Liu ◽

Xi Chen ◽

Yina Qiao

Keyword(s):

Central Asia ◽

Human Activities ◽

Climatic Changes ◽

Available Water

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Paleoecology and high-resolution paleohydrology of a kettle peatland in upper Michigan

Quaternary Research ◽

10.1016/j.yqres.2003.07.013 ◽

2004 ◽

Vol 61 (1) ◽

pp. 1-13 ◽

Cited By ~ 70

Author(s):

Robert K. Booth ◽

Stephen T. Jackson ◽

Catherine E.D. Gray

Keyword(s):

High Resolution ◽

Climate Variability ◽

Time Scales ◽

Plant Macrofossils ◽

Testate Amoebae ◽

Climatic Changes ◽

Primary Objective ◽

History Of ◽

Past Climate Variability

We investigated the developmental and hydrological history of a Sphagnum-dominated, kettle peatland in Upper Michigan using testate amoebae, plant macrofossils, and pollen. Our primary objective was to determine if the paleohydrological record of the peatland represents a record of past climate variability at subcentennial to millennial time scales. To assess the role of millennial-scale climate variability on peatland paleohydrology, we compared the timing of peatland and upland vegetation changes. To investigate the role of higher-frequency climate variability on peatland paleohydrology, we used testate amoebae to reconstruct a high-resolution, hydrologic history of the peatland for the past 5100 years, and compared this record to other regional records of paleoclimate and vegetation. Comparisons revealed coherent patterns of hydrological, vegetational, and climatic changes, suggesting that peatland paleohydrology responded to climate variability at millennial to sub-centennial time scales. Although ombrotrophic peatlands have been the focus of most high-resolution peatland paleoclimate research, paleohydrological records from Sphagnum-dominated, closed-basin peatlands record high-frequency and low-magnitude climatic changes and thus represent a significant source of unexplored paleoclimate data.

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