@InProceedings{JustinoMare:2012:InAnIc,
               author = "Justino, F. and Marengo, J.",
          affiliation = "Federal University of Vi{\c{c}}osa, Vi{\c{c}}osa, Minas Gerais, 
                         Brazil, Earth System Science Center, National and {Instituto 
                         Nacional de Pesquisas Espaciais (INPE)}",
                title = "Influence of Antarctic Ice Sheet Lowering on Southern Hemisphere 
                         Climate",
            booktitle = "Abstracts...",
                 year = "2012",
         organization = "International Conference on Earth System Modelling, 3.",
             abstract = "It has long beeen recongnized that the Earths climate system is 
                         influenced by the configuration of large-scale topography which 
                         plays a significant role to characterize the dynamical and 
                         thermodynamical aspects of the climate/ weather. The impact of 
                         changes in the Antarctic Ice Sheet (AIS) topography on the climate 
                         system may be usefully investigated on the basis of coupled 
                         climate experiments, designed to inter-compare the nature of the 
                         atmospheric and oceanic circulation under modern conditions and 
                         those conditions induced by anomalous AIS topographic forcing. 
                         This approach provides an unique opportunity to study the 
                         importance of changes in the AIS topography in amplifying global 
                         climate features in the time-space domain. Furthermore, it may 
                         contribute to the understanding of the climate occured in the 
                         transition from Eocene to Oligocene (between 30 and 35 Million 
                         years ago) during the onset of the Antarctic ice sheet. In order 
                         to investigate the climate response to changes in the AIS 
                         topography, two model simulations have been performed with the 
                         SPEEDO (Speedy-Ocean) coupled model. A modern simulation driven by 
                         present day boundary conditions (MOD) and a second experiment 
                         which includes modification in the AIS topography (AIS). In this 
                         simulation the height of the Antarctica ice sheet is lowered by 
                         25%. This modification reduces the top of the Antarctica ice sheet 
                         by approximately 700-1000 m. The new topography configuration may 
                         characterize the transition during the middle and late Miocene (15 
                         million years ago). The results show that oceanic changes between 
                         both simulations are evident in the Southern Ocean with values as 
                         higher as 4C in the AIS simulation as compared to the CTR. These 
                         changes are more pronounced in the Atlantic and Indian oceans 
                         which is in close agreement with the weakening of the wind stress, 
                         and enhanced southward advection. Moreover, reduced AIS also leads 
                         to weaker zonal windstress between 40S-60S which feeds back the 
                         initial warming tendency. Modification of the AIS topography 
                         induces substantial modification in the AABW but not in the NADW 
                         differently of what is expected based on the interhemispheric 
                         seesaw assumption. In this sense, one may conclude that the 
                         dynamical and mechanical effects of the Antarctic ice sheet 
                         topography are crucial to determine past, present and future 
                         climates.",
               volume = "3ICESM-14, 2012",
        urlaccessdate = "02 maio 2024"
}