Back to Search
Start Over
Influence of the Southern Annular Mode on the sea iceāocean system
- Source :
- EPIC3Journal of Geophysical Research, 109, C09005
- Publication Year :
- 2004
- Publisher :
- American Geophysical Union (AGU), 2004.
-
Abstract
- [1] The global sea ice - ocean model ORCA2-LIM, driven by the NCEP/NCAR ( National Centers for Environmental Prediction-National Center for Atmospheric Research) reanalysis daily 2-m air temperatures and 10-m winds and by monthly climatologies for precipitation, cloud cover, and relative humidity, is used to investigate the impact of the Southern Annular Mode (SAM) on the Antarctic sea ice-ocean system. Our results suggest that the response of the circumpolar Southern Ocean consists of an annular and a nonannular component. For the sea ice cover, the non-annular component seems to be the most important. The annular component strongly affects the overall patterns of the upper ocean circulation. When the SAM is in its positive phase, a northward surface Ekman drift, a downwelling at about 45 degreesS, and an upwelling in the vicinity of the Antarctic continent are simulated. The non-annular component has a significant impact at the regional scale, especially in the Weddell, Ross, Amundsen, and Bellingshausen Seas. In those regions, the pressure pattern associated with the SAM induces meridional winds which advect warmer air in the Weddell Sea and around the Antarctic Peninsula and colder air in the Amundsen and Ross Seas. This implies a dipole response of sea ice to the SAM, with on average a decrease in ice area in the Weddell Sea and around the Antarctic Peninsula and an increase in the Ross and Amundsen Seas during years with a high SAM index. The long-term trend in the observed sea ice area does not appear to be related to the trend in the SAM index.
- Subjects :
- Atmospheric Science
010504 meteorology & atmospheric sciences
Soil Science
Antarctic sea ice
Aquatic Science
010502 geochemistry & geophysics
Oceanography
01 natural sciences
Geochemistry and Petrology
Earth and Planetary Sciences (miscellaneous)
Sea ice
Cryosphere
14. Life underwater
0105 earth and related environmental sciences
Earth-Surface Processes
Water Science and Technology
Drift ice
Weddell Sea Bottom Water
geography
geography.geographical_feature_category
Ecology
Ocean current
Paleontology
Forestry
Arctic ice pack
Geophysics
13. Climate action
Space and Planetary Science
Climatology
Sea ice thickness
Geology
Subjects
Details
- ISSN :
- 01480227
- Volume :
- 109
- Database :
- OpenAIRE
- Journal :
- Journal of Geophysical Research
- Accession number :
- edsair.doi.dedup.....4ab264ac1d6a69cde7838df56373420d
- Full Text :
- https://doi.org/10.1029/2004jc002403