Towards a quantitative understanding of millennial-scale Antarctic Warming Events
The interhemispheric temperature response to a meltwater-induced weakening of the Atlantic Meridional Overturning Circulation (AMOC) is characterized by a Northern Hemispheric cooling and a Southern Hemispheric warming. This so-called bipolar seesaw pattern explains many millennialscale features ide...
| Main Authors: | , , , , , , , |
|---|---|
| Other Authors: | |
| Format: | Text |
| Language: | English |
| Published: |
2010
|
| Subjects: | |
| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.226.919 http://nldr.library.ucar.edu/repository/assets/osgc/fy10_201704.pdf |
| Summary: | The interhemispheric temperature response to a meltwater-induced weakening of the Atlantic Meridional Overturning Circulation (AMOC) is characterized by a Northern Hemispheric cooling and a Southern Hemispheric warming. This so-called bipolar seesaw pattern explains many millennialscale features identified in paleo-proxy records from both hemispheres. Here we present modeling evidence that suggests that the Southern Hemispheric response to a weakening of the AMOC includes elements that have previously been overlooked. Under present-day conditions an AMOC weakening leads to an intensification of the negative phase of the Pacific South America (PSA) pattern with its southernmost pole north of the Ross Sea. An intensified PSA pattern may lead to a regional cooling of Marie Byrd Land, thereby favoring an in-phase temperature relationship between the Northern Hemisphere and the western side of the West Antarctic Ice Sheet on millennial timescales. However, under glacial conditions due to reduced |
|---|