Winter Sea Ice Concentration Research Articles

Relationships between sea ice concentration, sea surface temperature and demographic traits of thin-billed prions

Understanding the effects of environmental variations on ecosystems is a major topic in ecology. In this study, we estimated demographic parameters of a seabird population, the thin-billed prion (Pachyptila belcheri) at Kerguelen Islands, and then tested for relationships with inter-annual variations of climatic indices, using long-term capture–recapture data. The annual adult survival probability was 0.825±0.009 and the breeding success was 0.519±0.090. Sea surface temperature anomalies were negatively related with breeding success. By contrast, winter sea ice concentration in the Antarctic seasonal ice zone seemed to negatively influence adult survival. This suggests a connection between sub-Antarctic and Antarctic ecosystems. The actual context of large climatic changes in the Austral Ocean seems to explain a large part of the decreasing trends observed for both the breeding success and the adult survival. Thus, a decrease of the population size of thin-billed prions at Kerguelen could be strongly suspected in the near future.

Minimal Antarctic sea ice during the Pliocene

Research Article| February 01, 2005 Minimal Antarctic sea ice during the Pliocene J.M. Whitehead; J.M. Whitehead 1Department of Geology, University of Nebraska, Lincoln, Nebraska 68588-0340, USA, and Institute of Antarctic and Southern Ocean Studies, University of Tasmania, Hobart, Tasmania 7005, Australia Search for other works by this author on: GSW Google Scholar S. Wotherspoon; S. Wotherspoon 2School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania 7005, Australia Search for other works by this author on: GSW Google Scholar S.M. Bohaty S.M. Bohaty 3Earth Sciences Department, University of California, Santa Cruz, California 95064, USA Search for other works by this author on: GSW Google Scholar Author and Article Information J.M. Whitehead 1Department of Geology, University of Nebraska, Lincoln, Nebraska 68588-0340, USA, and Institute of Antarctic and Southern Ocean Studies, University of Tasmania, Hobart, Tasmania 7005, Australia S. Wotherspoon 2School of Mathematics and Physics, University of Tasmania, Hobart, Tasmania 7005, Australia S.M. Bohaty 3Earth Sciences Department, University of California, Santa Cruz, California 95064, USA Publisher: Geological Society of America Received: 13 Jul 2004 Revision Received: 04 Oct 2004 Accepted: 07 Oct 2004 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (2005) 33 (2): 137–140. https://doi.org/10.1130/G21013.1 Article history Received: 13 Jul 2004 Revision Received: 04 Oct 2004 Accepted: 07 Oct 2004 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation J.M. Whitehead, S. Wotherspoon, S.M. Bohaty; Minimal Antarctic sea ice during the Pliocene. Geology 2005;; 33 (2): 137–140. doi: https://doi.org/10.1130/G21013.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Antarctic sea-ice concentration at Ocean Drilling Program Sites 1165 (64.380°S, 67.219°E) and 1166 (67.696°S, 74.787°E) was lower than today through much of the Pliocene. The low sea-ice concentration is evident from the proportion of the diatom Eucampia antarctica with intercalary valves (Eucampia index). This sea-ice proxy was calibrated by using modern diatom data obtained from core-top samples and winter sea-ice concentration data (September average through 1979–1987). The modern relationship is expressed as a binomial generalized linear model (modern sea-ice model). This model was applied to the Pliocene Eucampia index within a 95% tolerance interval (obtained from bootstrap estimates). The results indicate that reduced winter sea-ice concentrations persisted through much of the Pliocene and at times were 78% and 61% relatively less concentrated than today at Sites 1165 and 1166, respectively. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

Variability of the Northern Annular Mode's signature in winter sea ice concentration

Historical winter sea ice concentration data are used to examine the relation between the Northern Annular Mode (NAM) and the sea ice concentration in the Nordic seas over the past 50 years. The well known basic response pattern of a seesaw between the Labrador Sea and the Greenland, Iceland and Barents seas is being reproduced. However, the response is not robust in the Greenland and Iceland seas. There the observed variability has a more complex relationship with surface temperatures and winds. We divide the sea ice response into three spectral bands: high (P 15 year) filtered NAM indices. This division is motivated by the expected slow response of the ocean circulation which might play a significant role in the Greenland and Iceland seas. The response to the NAM is also examined separately for the periods before and after 1976 to identify variations due to the relocation of the northern centre of the North Atlantic Oscillation.

Variability of the Northern Annular Mode’s signature in winter sea ice concentration

Historical winter sea ice concentration data are used to examine the relation between the Northern Annular Mode (NAM) and the sea ice concentration in the Nordic seas over the past 50 years. The well known basic response pattern of a seesaw between the Labrador Sea and the Greenland, Iceland and Barents seas is being reproduced. However, the response is not robust in the Greenland and Iceland seas. There the observed variability has a more complex relationship with surface temperatures and winds. We divide the sea ice response into three spectral bands: high (P < 5 year), band (5 < P < 15 year), and low pass (P > 15 year) filtered NAM indices. This division is motivated by the expected slow response of the ocean circulation which might play a significant role in the Greenland and Iceland seas. The response to the NAM is also examined separately for the periods before and after 1976 to identify variations due to the relocation of the northern centre of the North Atlantic Oscillation.

Trends and variability of sea ice in Baffin Bay and Davis Strait, 1953–2001

The extent and duration of sea ice in Baffin Bay and Davis Strait has a major impact on the timing and strength of the marine production along West Greenland. The advance and retreat of the sea ice follows a predictable pattern, with maximum extent typically in March. We examine the area of sea ice in March in three overlapping study regions centred on Disko Bay on the west coast of Greenland. Sea ice concentration estimates derived from satellite passive microwave data are available for the years 1979&ndash;2001. We extend the record back in time by digitizing ice charts from the Danish Meteorological Institute, 1953&ndash;1981. There is reasonable agreement between the chart data and the satellite data during the three years of overlap: 1979&ndash;1981. We find a significant increasing trend in sea ice for the 49-year period (1953&ndash;2001) for the study regions that extend into Davis Strait and Baffin Bay. The cyclical nature of the wintertime ice area is also evident, with a period of about 8 to 9 years. Correlation of the winter sea ice concentration with the winter North Atlantic Oscillation (NAO) index shows moderately high values in Baffin Bay. The correlation of ice concentration with the previous winter&rsquo;s NAO is high in Davis Strait and suggests that next winter&rsquo;s ice conditions can be predicted to some extent by this winter&rsquo;s NAO index.