02171nas a2200241   4500008004100000245010500041210006900146300001200215490000700227520140000234100002001634700001601654700002101670700001501691700002501706700002201731700001801753700001901771700002001790700001801810700001701828856008401845       2010                        eng d00aResults from the Ice-Sheet Model Intercomparison ProjectHeinrich Event INtercOmparison (ISMIP HEINO)0 aResults from the IceSheet Model Intercomparison ProjectHeinrich   a371-3830 v563 aResults from the Heinrich Event INtercOmparison (HEINO) topic of the Ice-Sheet Model Intercomparison Project (ISMIP) are presented. ISMIP HEINO was designed to explore internal large-scale ice-sheet instabilities in different contemporary ice-sheet models. These instabilities are of interest because they are a possible cause of Heinrich events. A simplified geometry experiment reproduces the main characteristics of the Laurentide ice sheet, including the sedimented region over Hudson Bay and Hudson Strait. The model experiments include a standard run plus seven variations. Nine dynamic/thermodynamic ice-sheet models were investigated; one of these models contains a combination of the shallow-shelf (SSA) and shallow-ice approximation (SIA), while the remaining eight models are of SIA type only. Seven models, including the SIA-SSA model, exhibit oscillatory surges with a period of &#8764;1000 years for a broad range of parameters, while two models remain in a permanent state of streaming for most parameter settings. In a number of models, the oscillations disappear for high surface temperatures, strong snowfall and small sediment sliding parameters. In turn, low surface temperatures and low snowfall are favourable for the ice-surge cycles. We conclude that further improvement of ice-sheet models is crucial for adequate, robust simulations of cyclic large-scale instabilities.1 aCalov, Reinhard1 aGreve, Ralf1 aAbe-Ouchi, Ayako1 aBueler, E.1 aHuybrechts, Philippe1 aJohnson, Jesse, V1 aPattyn, Frank1 aPollard, David1 aRitz, Catherine1 aSaito, Fuyuki1 aTarasov, Lev  uhttp://www.ingentaconnect.com/content/igsoc/jog/2010/00000056/00000197/art00001