HR: 16:50h
AN: OS12C-04    [PDF]
TI: Deep North Atlantic Freshening Simulated in a Coupled Climate Model
AU: * Wu, P
EM: peili.wu@metoffice.com
AF: Hadley Centre, Met Office London Road, Bracknell, RG12 2SY United Kingdom
AU: Wood, R
AF: Hadley Centre, Met Office London Road, Bracknell, RG12 2SY United Kingdom
AU: Stott, P
AF: Hadley Centre, Met Office London Road, Bracknell, RG12 2SY United Kingdom
AB: We have analysed an ensemble of four coupled climate model (HadCM3) simulations with all major historical forcings (natural and anthropogenic). The model has simulated a sustained freshening trend in the deep sub-polar North Atlantic Ocean during the past four decades, which is very similar to recent observations. The source of the freshening is associated with decreased ice cover and increased river runoffs in the Arctic. We do not find any significant changes in E-P over the polar ocean regions. Along with this deep ocean freshening, we find an upward trend in the North Atlantic overturning circulation. The model projects a rapid reverse in the early 21st century of the freshening trend in Labrador Sea due to the collapse of deep convection under increasing anthropogenic forcing.
DE: 4200 OCEANOGRAPHY: GENERAL
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting