Variations in Antarctic sea ice conditions and relationships with Southern Hemisphere cyclonic activity, winters 1973–77

1983 ◽  
Vol 32 (1) ◽  
pp. 1-22 ◽  
Author(s):  
A. M. Carleton
Keyword(s):  
Sea Ice ◽  
Southern Hemisphere ◽  
Cyclonic Activity ◽  
Antarctic Sea Ice ◽  
Ice Conditions

Connecting Antarctic Sea Ice and Mid-latitude Precipitation

2021 ◽  
Author(s):  
Tristan Rendfrey ◽  
Ashley Payne
Keyword(s):  
Sea Ice ◽  
Southern Hemisphere ◽  
Reanalysis Data ◽  
Lower Latitude ◽  
Sea Ice Extent ◽  
Weather Patterns ◽  
Antarctic Sea Ice ◽  
Ice Coverage ◽  
Precipitation Timing ◽  
Analogous Relation

<div><span>Climatic changes induce many significant changes to long standing weather patterns. These mechanisms interact to drive consequences that may not be immediately obvious. One such connection involves the apparent relationship between polar sea ice extent and mid-latitude precipitation timing and location. This correlation, its mechanisms, and possible influences on weather are decently understood with respect to the Northern Hemisphere. However, the analogous relation for the Southern Hemisphere has been less studied. This provides an opportunity to examine connections between polar conditions and mid-latitude weather.</span></div><div> </div><div><span>We explore the teleconnection between sea ice extent and lower latitude precipitation over the Southern Hemisphere. We investigate this relationship through observations of sea ice coverage using ICESat and ICESat-2 compared with reanalysis data via MERRA-2 in order to understand the variability of sea ice extent and its impact on midlatitude precipitation over the Southern Hemisphere. This study particularly examines the importance of seasonality and regional variations of the relationship.</span></div>

How Do Weakening of the Stratospheric Polar Vortex in the Southern Hemisphere Affect Regional Antarctic Sea Ice Extent?

2021 ◽  
Vol 48 (11) ◽  
Author(s):  
Shaoyin Wang ◽  
Jiping Liu ◽  
Xiao Cheng ◽  
Tobias Kerzenmacher ◽  
Yongyun Hu ◽  
...  
Keyword(s):  
Sea Ice ◽  
Southern Hemisphere ◽  
Polar Vortex ◽  
Sea Ice Extent ◽  
Stratospheric Polar Vortex ◽  
Antarctic Sea Ice

Dynamical mechanism of the poleward intensification of the Southern Hemispheric Westerlies due to sea ice extent change

2020 ◽  
Author(s):  
Hyeong-Gyu Kim ◽  
Joowan Kim ◽  
Sang-Yoon Jun ◽  
Seong-Joong Kim
Keyword(s):  
Southern Ocean ◽  
Sea Ice ◽  
Ocean Circulation ◽  
Atmospheric Temperature ◽  
Sea Ice Extent ◽  
Dynamical Mechanism ◽  
Antarctic Sea Ice ◽  
Crucial Component ◽  
Ice Conditions ◽  
Geological Timescale

<p>Paleoclimate data shows a good correlation between the concentration of CO<sub>2</sub> and atmospheric temperature in the geological timescale. Many studies compare the Last Glacial Maximum (LGM) and the Pre-Industrial era (PI), to understand the coupling processes. A popular mechanism explaining this coupling process is a modulation of the ocean circulation and related CO<sub>2</sub> emission over the Southern Ocean due to atmospheric westerly. The atmospheric westerly plays an important role in driving ocean circulation; however, the related processes are not fully understood for the LGM period.</p><p>In this study, we examine physical processes determining the characteristics of the atmospheric westerly focusing on the Southern Ocean. Atmospheric states for LGM and PI are reproduced using a coupled earth system model with different sea ice conditions. A poleward intensification of the Southern Hemispheric Westerlies is observed for the LGM experiment. A comparison to PI shows that the meridional temperature gradient largely determines this intensification, and the enhanced meridional gradient is observed due to decreased heat flux from the subantarctic ocean in the LGM experiment. This result suggests that the Antarctic sea ice is a crucial component for understanding the Southern Hemispheric Westerly.</p>

scholarly journals Extreme ecological response of a seabird community to unprecedented sea ice cover

2015 ◽  
Vol 2 (5) ◽  
pp. 140456 ◽  
Author(s):  
Christophe Barbraud ◽  
Karine Delord ◽  
Henri Weimerskirch
Keyword(s):  
Sea Ice ◽  
Extreme Event ◽  
Species Abundance ◽  
Ice Cover ◽  
Seabird Species ◽  
Antarctic Sea Ice ◽  
Top Predators ◽  
Total Failure ◽  
Ice Conditions ◽  
Abundance And Distribution

Climate change has been predicted to reduce Antarctic sea ice but, instead, sea ice surrounding Antarctica has expanded over the past 30 years, albeit with contrasted regional changes. Here we report a recent extreme event in sea ice conditions in East Antarctica and investigate its consequences on a seabird community. In early 2014, the Dumont d'Urville Sea experienced the highest magnitude sea ice cover (76.8%) event on record (1982–2013: range 11.3–65.3%; mean±95% confidence interval: 27.7% (23.1–32.2%)). Catastrophic effects were detected in the breeding output of all sympatric seabird species, with a total failure for two species. These results provide a new view crucial to predictive models of species abundance and distribution as to how extreme sea ice events might impact an entire community of top predators in polar marine ecosystems in a context of expanding sea ice in eastern Antarctica.

scholarly journals The effect of Antarctic sea ice on the Southern Hemisphere atmosphere during the southern summer

2010 ◽  
Vol 36 (7-8) ◽  
pp. 1403-1417 ◽  
Author(s):  
M. N. Raphael ◽  
W. Hobbs ◽  
I. Wainer
Keyword(s):  
Sea Ice ◽  
Southern Hemisphere ◽  
Antarctic Sea Ice

scholarly journals The Roles of Wind and Sea Ice in Driving the Deglacial Change in the Southern Ocean Upwelling: A Modeling Study

2021 ◽  
Vol 13 (1) ◽  
pp. 353
Author(s):  
Gagan Mandal ◽  
Shih-Yu Lee ◽  
Jia-Yuh Yu
Keyword(s):  
Southern Ocean ◽  
Sea Ice ◽  
Southern Hemisphere ◽  
Wind Stress ◽  
Deep Ocean ◽  
Last Deglaciation ◽  
Buoyancy Forcing ◽  
Antarctic Sea Ice ◽  
Freshwater Fluxes ◽  
Deep Ocean Water

The Southern Ocean (SO) played a fundamental role in the deglacial climate system by exchanging carbon-rich deep ocean water with the surface. The contribution of the SO’s physical mechanisms toward improving our understanding of SO upwelling’s dynamical changes is developing. Here, we investigated the simulated transient SO atmosphere, ocean, and sea ice evolution during the last deglaciation in a fully coupled Earth system model. Our results showed that decreases in SO upwelling followed the weakening of the Southern Hemisphere surface westerlies, wind stress forcing, and Antarctic sea ice coverage from the Last Glacial Maximum to the Heinrich Stadial 1 and the Younger Dryas. Our results support the idea that the SO upwelling is primarily driven by wind stress forcing. However, during the onset of the Holocene, SO upwelling increased while the strength of the wind stress decreased. The Antarctic sea ice change controlled the salt and freshwater fluxes, ocean density, and buoyancy flux, thereby influencing the SO’s dynamics. Our study highlighted the dynamic linkage of the Southern Hemisphere westerlies, ocean, and sea ice in the SO’s latitudes. Furthermore, it emphasized that zonal wind stress forcing and buoyancy forcing control by sea ice together regulate the change in the SO upwelling.

scholarly journals Radiometrie measurements of sea-ice surface temperature in East Antarctica

1998 ◽  
Vol 27 ◽  
pp. 466-470
Author(s):  
Kelvin J. Michael ◽  
Clemente S. Hungria ◽  
R. A. Massom
Keyword(s):  
Sea Ice ◽  
Surface Temperature ◽  
Snow Cover ◽  
Open Water ◽  
Thermal Infrared ◽  
Near Surface ◽  
Video Footage ◽  
Antarctic Sea Ice ◽  
Ice Surface ◽  
Ice Conditions

This paper presents surface temperature data collected over East Antarctic sea ice by two thermal infrared radiometers mounted on the RSV Aurora Australis in March-May 1993. Operating at wavelengths equivalent to those utilised by channels 4 and 5 of AVHRR and similar channels of ATSR, the radiometers provided high-reso-lution data on surface (skin) temperature along the ship track. Additional information on the sea-ice conditions was obtained from hourly observations made from The ship's bridge, video footage and direct measurements made at ice stations. Following calibration, time series of temperatures from each of the radiometers were compared wi th ice-surface and near-surface air temperatures. Observed changes in the surface temperature are related to different snow and ice conditions. For a given air temperature, the surface temperature depends upon the thickness of ice and its snow cover. While open water areas (leads) have temperatures near -2.0°C, thick ice is characterised by surface temperatures which approximate those of the air. Taken as a whole, the along-track profile of surface temperature provides a proxy estimate of The proportion of open water and thin ice with in the pack. The presence of a snow cover has a significant effect on the surface temperature. It is anticipated that the results will be of use in the validation of sea-ice models and satellite thermal infrared data.

Sign in / Sign up

Export Citation Format

Share Document