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@InProceedings{DurrantPezzSimmSmit:2006:AsSoAu,
               author = "Durrant, Thomas Hawkins and Pezza, Alexandre Bernandes and 
                         Simmonds, Ian and Smith, Ian",
          affiliation = "The University of Melbourne, Parkville VIC 3010, Australia 
                         (Durrant and Pezza)",
                title = "Sea ice extension around Antarctica: Association with southern 
                         Australian rainfall via changes in Southern Hemisphere cyclone and 
                         anticyclone behaviour",
            booktitle = "Proceedings...",
                 year = "2006",
               editor = "Vera, Carolina and Nobre, Carlos",
                pages = "189--194",
         organization = "International Conference on Southern Hemisphere Meteorology and 
                         Oceanography, 8. (ICSHMO).",
            publisher = "American Meteorological Society (AMS)",
              address = "45 Beacon Hill Road, Boston, MA, USA",
             keywords = "Antarctic sea ice, australian rainfall, Southern Hemsiphere 
                         circulation.",
             abstract = "Interactions occurring over the Southern Ocean between the 
                         Antarctic sea ice, the atmosphere and the ocean form a vastly 
                         complex system. The sparsity of data available over this region 
                         has traditionally greatly inhibited the study of this system, a 
                         short-falling which has been significantly improved in recent 
                         times by the advent of computer and satellite technology. 
                         Understanding of Antarctic sea ice and its interactions with the 
                         Southern Ocean circulation is of particular interest in Australia 
                         due to its proximity to the south Australian coast and potential 
                         influences on Australian climate. The aim of this study is to 
                         explore the relationship and possible connection between Antarctic 
                         sea ice extent and rainfall in southern Australia. An initial 
                         statistics component examines correlations between sea ice extent 
                         and rainfall in both Melbourne and Perth, guiding later work 
                         investigating associated changes in regional cyclone and 
                         anticyclone behaviour. Although this relationship between sea ice 
                         extent and southern ocean circulation has been the subject of a 
                         number of studies, this is the first detailed analysis performed 
                         focussing on the Australian region. The study is performed for the 
                         period for which reliable remotely sensed sea ice data is 
                         available, namely 1979-2003. Correlations between Perth (located 
                         on the west coast) and Melbourne (east coast) rainfall data and 
                         sea ice extent data suggest that these two quantities are 
                         inversely related, with high sea ice extent associated with low 
                         rainfall and vice versa. Dividing the ice pack into five roughly 
                         equal longitudinal sectors, local and slightly upstream sectors 
                         appear more influential in the Australian region than the pack 
                         considered as a whole, specifically, the Indian Ocean sector is 
                         most associated with Perth rainfall, while that of Melbourne is 
                         related to the West Pacific sector. Furthermore, results suggest 
                         the strongest association occurs in winter. The Melbourne 
                         University Cyclone Tracking Scheme is employed to investigate 
                         associated changes in regional cyclone and anticyclone behaviour, 
                         analysing the NCEP2 reanalysis data set over the same period. The 
                         track statistics of system density and system depth (a measure of 
                         system strength) are analysed for composites of years when the sea 
                         ice is high and low for both the Indian and West Pacific sectors 
                         in winter. Generally, low (high) sea ice is associated with 
                         increased (decreased) cyclone system density over regions of 
                         southern Australia. This suggests physical agreement with the 
                         observed negative correlations between ice and rainfall in 
                         Melbourne and Perth, given that regions of increased cyclone 
                         system density are likely to receive more rainfall. Depth 
                         anomalies showed consistent patterns, with strong anomalous areas 
                         appearing over the Southern Ocean in areas of cyclone paths 
                         associated with frontal systems affecting Australia. Anticyclone 
                         patterns are in agreement and compliment what was found for the 
                         cyclones. Furthermore, results were consistent with the 
                         correlations regarding specific regions of influence, adding 
                         weight to these findings and overall providing a coherent physical 
                         mechanism for the observed connection. It is not possible from 
                         this kind of analysis to infer if the ice is driving these 
                         circulation changes, or being driven by them.",
  conference-location = "Foz do Igua{\c{c}}u",
      conference-year = "24-28 Apr. 2006",
             language = "en",
         organisation = "American Meteorological Society (AMS)",
                  ibi = "cptec.inpe.br/adm_conf/2005/10.07.01.54",
                  url = "http://urlib.net/ibi/cptec.inpe.br/adm_conf/2005/10.07.01.54",
           targetfile = "189-194.pdf",
                 type = "Climate and Cryosphere of the Antarctic region",
        urlaccessdate = "16 jun. 2024"
}


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