Annual report 2005-06.indd - Antarctic Climate and Ecosystems ...

sea-level riseOutput / Milestone Date ProgressRevised projections for future sea-levelchange during the 21 st century and on longertime-scales2006,2010Showed that over the last 15 years sea levelshave been tracking near the upper bound ofthe IPCC TAR projections (Submitted to Nature,2006).Revised estimates of future ocean thermalexpansionEstimate of the future contribution ofthe Antarctic and Greenland ice sheetsto sea-level change using an improvedhigh-resolution ice sheet-system model(including ice stream-ice shelf interaction, fullthermodynamics and flow anisotropy) andchanges in meteorological forcingEstimates of the response of ice shelves toglobal warming from improved models of iceshelf-ocean interaction (validated againstfield observations and remote sensing datafrom the Amery Ice Shelf); prediction, fromimproved models of ice stream-ice shelfboundaries, of the consequence of ice shelfcollapse on the discharge of grounded iceEstimates of the historical impacts of sealevelchange at key locationsEstimates of the historical frequency ofextreme events from observational (andproxy) recordsEstimates of the expected impacts of sealevelchange at key locationsSelection of key locations for more detailedstudiesEstimates of the changes in frequency ofextreme events from numerical modellingstudies2005,2009Revised estimates for a number of thecontribution to the rate of sea-level rise havebeen completed (see below) and these havebeen incorporated in revised projections to bepublished under IPCC banner early 2007.2005: Produced estimates of 21 st centuryocean thermal expansion from the CSIROMark 3 model that will appear in the IPCC 4 thAssessment Report.2010 An ice shelf ice stream transition modelis under test (see next milestone). Icedeformation experiments have collected dataon flow of anisotropic samples of Antarctic ice(2004-06) and theoretical models of anisotropicice flow will be tested in 2006-07.2006-09 The ACE CRC ice shelf model has been usedto explore the dynamics of the Mertz Glaciertongue and its response to global warming(2006). The model will also be applied to thelarger Amery ice shelf (2006-07). The iceshelf model has also been extended (testing inprogress in 2006) to study the ice stream-iceshelf transition by adding a basal friction term,to enable studies of influences on grounded ice.A model of frazil ice growth has been developed(2004-06) as a step towards understandingmarine ice accretion beneath the Amery iceshelf.2005 Changes in the frequency of extreme events ata number of locations have been determined.There is significant interest in these results andwe are being requested to do further studies.2004 2004 and 2006: Showed that the frequency ofextreme sea-level events of a given magnitudeat Fremantle and Sydney has increased byabout a factor of 2-3 during the 20 th century.2010 A study for the Victorian coast has beencompleted, following a pre-ACE CRC study ofthe Cairns area.2004 Completed 2004: South coast of Australiachosen as first study site.2009 Study completed for eastern Victorian coastline,extension to other parts of coastline is ongoing.48 Antarctic Climate & Ecosystems CRC - Annual Report 2005-06