Publications by authors named "Michael Kalk"
The last glacial period was punctuated by cold intervals in the North Atlantic region that culminated in extensive iceberg discharge events. These cold intervals, known as Heinrich Stadials, are associated with abrupt climate shifts worldwide. Here, we present CO measurements from the West Antarctic Ice Sheet Divide ice core across Heinrich Stadials 2 to 5 at decadal-scale resolution.
View Article and Find Full Text PDFDuring the last ice age, the Laurentide Ice Sheet exhibited extreme iceberg discharge events that are recorded in North Atlantic sediments. These Heinrich events have far-reaching climate impacts, including widespread disruptions to hydrological and biogeochemical cycles. They occurred during Heinrich stadials-cold periods with strongly weakened Atlantic overturning circulation.
View Article and Find Full Text PDFArticle Synopsis
- - The text discusses the relationship between atmospheric carbon dioxide (CO2) levels and global climate, focusing on the rise of CO2 during the last glacial termination roughly 23,000 to 9,000 years ago, emphasizing the uncertain processes behind this increase.
- - New data from a West Antarctic ice core reveals that while CO2 changes generally align with Antarctic temperature shifts, there are abrupt CO2 increases tied to Northern Hemisphere climate changes, notably occurring in three rapid steps of 10 to 15 parts per million each.
- - The findings suggest that while Southern Ocean dynamics are important for understanding historical CO2 increases, there are also shorter-term fluctuations in CO2 linked to Atlantic ocean circulation that current Earth system models may not adequately account