The Effects of Late-Quaternary Climatic Changes and Glacioisostatic Rebound on Lake Level Fluctuations and Benthos of Lake Michigan

Palaios ◽  
1987 ◽  
Vol 2 (5) ◽  
pp. 514
Author(s):  
Collette Dick Burke
1993 ◽  
Vol 40 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Michel Magny

AbstractChronological correlations established at different time scales among the lake-level fluctuations in the Jura and French Subalpine ranges, glacier movements in the Swiss and Austrian Alps, and the atmospheric 14C record during the last 7 millennia show coincidences between lake-level rises, glacier advances, and high 14C production and vice versa. These correspondences suggest that the short-term 14C variations may be an empirical indicator of Holocene palaeoclimates and argue for possible origins of Holocene climatic oscillations: (1) The varying solar activity refers to secular climatic oscillations and to major climatic deteriorations showing a ca. 2300-yr periodicity. (2) A question is raised about a relationship between the earth's magnetic field and climate. First, the weak-strength periods of the earth's dipole magnetic field (between 3800 and ca. 2500 B.C.) coincide with higher climate variability, and vice versa. Second, the ca. 2300-yr periods revealed by the 14C record and also by the major climatic deteriorations re. corded in Jurassian lakes (ca. 1500 A.D., ca. 800 B.C., and ca. 3500 B.C.) coincide with the ca. 2300-yr periods revealed by the earth's nondipole geomagnetic field. The present warming induced by anthropogenic factors should be intensified during the next few centuries by natural factors of climate evolution.


2020 ◽  
Author(s):  
Julius Jara-Muñoz ◽  
Amotz Agnon ◽  
Jens Fohlmeister ◽  
Jürgen Mey ◽  
Norbert Frank ◽  
...  

<p><span>High-resolution records of lake-level changes are crucial to elucidate the impact of local and global climatic changes in lacustrine basins. The Late Quaternary evolution of the Dead Sea has been characterized by substantial variability apparently linked with global climatic changes, beign subject of many research efforts since decades. Previous studies have defined two main lake phases, the Lake Lisan and the Dead Sea, the earlier was a highstand period that lasted between ~70 and ~15 ka, the  latter was the lowstand period that persisted until the present. Here we focus on the switch between Lake Lisan and Dead Sea studying fossil lake shorelines, a sequence that comprises dozens of levels exposed along the rims of the Dead Sea, containing abundant fossil stromatolites that we dated by mean of radiocarbon and U-decay series. We determined 90 radiocarbon and 35 U-Th ages from stromatolites from almost every shoreline level. We compared U-Th and radiocarbon ages to estimating a radiocarbon reservoir between 0.2 and 0.8 ka, used to correct the remaining radiocarbon ages before calibration. The resulting ages range between ~45  and ~20 ka. Dating was </span><span>complemented with analysis of stable oxygen and carbon isotopes. Furthermore, we applied a distributed hydrological balance model to constrain past precipitation and temperature conditions. Our results suggest that the duration of the last Lake Lisan highstand was shorter than previously estimated. Taking this at face value, the switch between Lake Lisan and Dead Sea occurred at ~28 ka, ~10 ka earlier than previously suggested. Oxygen and carbon isotopes show a consistent pattern, displaying a switch between wet and dry conditions at ~28 ka. Preliminary results from the hydrological model indicate a much stronger sensitivity of the lake level to precipitation amounts than to air temperature. From our results we can’t observe a clear link between global temperature variations and lake-level changes in the Lisan/Dead Sea lakes. Similar non-linear response to northern hemisphere climatic changes have been also documented in Holocene Dead Sea paleoclimatic records, suggesting that global climatic variations may led to variable lake-level responses. The results of this study adds further complexity to the understanding of factors controlling climate variability in the Dead Sea. </span></p>


2010 ◽  
Vol 218 (1-2) ◽  
pp. 86-93 ◽  
Author(s):  
G. Daut ◽  
R. Mäusbacher ◽  
J. Baade ◽  
G. Gleixner ◽  
E. Kroemer ◽  
...  

Nature ◽  
1976 ◽  
Vol 261 (5559) ◽  
pp. 385-390 ◽  
Author(s):  
F. Alayne Street ◽  
A. T. Grove

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