Academic Commons

Articles

How did the hydrologic cycle respond to the two-phase mystery interval?

Broecker, Wallace S.; Putnam, Aaron Ervin

Lake Estancia’s transition from a Big Dry episode during the first half of the Mystery Interval to a Big Wet episode during the second half has equivalents in records from across the planet. At the time of this transition, Chinese monsoons experienced pronounced weakening, closed-basin lakes in both the Great Basin of the western United States and in the southern Altiplano of South America underwent a major expansion, mountain glaciers in Southern Hemisphere middle latitudes had retreated, and the rates of increase of CO2 and of d18O in Antarctic ice underwent a decrease. Finally, the precipitous drop in dust rain over Antarctica and the Southern Ocean terminated as did a similar drop in the 13C to 12C ratio in atmospheric CO2. These changes are consistent with a southward shift of the thermal equator. The cause of such a shift is thought to be an expansion of sea ice caused by a shutdown in deep water production in the northern Atlantic. This creates a dilemma because a similar southward shift is an expected consequence of the Heinrich event #1 which initiated the Mystery Interval.

Geographic Areas

Files

  • thumnail for Broecker_2012Quaternary_Science_Reviews.pdf Broecker_2012Quaternary_Science_Reviews.pdf application/x-pdf 1.31 MB Download File

Also Published In

Title
Quaternary Science Reviews
DOI
https://doi.org/10.1016/j.quascirev.2012.09.024

More About This Work

Academic Units
Lamont-Doherty Earth Observatory
Geochemistry
Published Here
November 20, 2012