|
|
|
|
|
| Kelley, Samuel E.; Kaplan, Michael R.; Schaefer, Joerg M.; Andersen, Bjorn G.; Barrell, David J. A.; Putnam, Aaron E.; Denton, George H.; Schwartz, Roseanne; Finkel, Robert C.; Doughty, Alice M.. |
| Millennial-scale temperature variations in Antarctica during the period 80,000 to 18,000 years ago are known to anti-correlate broadly with winter-centric cold-warm episodes revealed in Greenland ice cores. However, the extent to which climate fluctuations in the Southern Hemisphere beat in time with Antarctica, rather than with the Northern Hemisphere, has proved a controversial question. In this study we determine the ages of a prominent sequence of glacial moraines in New Zealand and use the results to assess the phasing of millennial climate change. Forty-four Be-10 cosmogenic surface-exposure ages of boulders deposited by the Pukaki glacier in the Southern Alps document four moraine-building events from Marine Isotope Stage 3 (MIS 3) through to the... |
| Tipo: Text |
Palavras-chave: Be-10 surface-exposure dating; LGM; MIS 3; Southern Hemisphere; Westerly wind field; New Zealand. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00289/40068/39163.pdf |
| |
|
|
| Putnam, Aaron E.; Schaefer, Joerg M.; Denton, George H.; Barrell, David J. A.; Finkel, Robert C.; Andersen, Bjorn G.; Schwartz, Roseanne; Chinn, Trevor J. H.; Doughty, Alice M.. |
| Mountain glaciers worldwide have undergone net recession over the past century in response to atmospheric warming(1), but the extent to which this warming reflects natural versus anthropogenic climate change remains uncertain(2,3). Between about 11,500 years ago and the nineteenth century, progressive atmospheric cooling over the European Alps induced glacier expansion(2,4-6), culminating with several large-scale advances during the seventeen to nineteenth centuries(3). However, it is unclear whether this glacier behaviour reflects global or a more regional forcing. Here we reconstruct glacier fluctuations in the Southern Alps of New Zealand for the past 11,000 years using Be-10 exposure ages. We use those fluctuations to estimate the associated... |
| Tipo: Text |
|
| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00265/37625/36932.pdf |
| |
|
|
|
