present-day control run

version of the Community Climate System Model CCSM2.0.1 is revisited and adjusted by deepening the Greenland-Scotland ridge, changing oceanic mixing parameters, and applying a regional freshwater flux adjustment at high northern latitudes. The main purpose of these adjustments is to maintain a robus...

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Bibliographic Details
Main Author: M. Prange
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 2006
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.221.4427
http://www.palmod.uni-bremen.de/%7Emprange/os-4-151-2008.pdf
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Summary:version of the Community Climate System Model CCSM2.0.1 is revisited and adjusted by deepening the Greenland-Scotland ridge, changing oceanic mixing parameters, and applying a regional freshwater flux adjustment at high northern latitudes. The main purpose of these adjustments is to maintain a robust Atlantic meridional overturning circulation which collapses in the original model release. The paper describes the present-day control run of the adjusted model (referred to as “CCSM2/T31x3a”) which is brought into climatic equilibrium by applying a deep-ocean acceleration technique. The accelerated integration is extended by a 100-year synchronous phase. The simulated meridional overturning circulation has a maximum of 14×10 6 m 3 s −1 in the North Atlantic. The CCSM2/T31x3a control run is evaluated against observations and simulations with other climate models. Most shortcomings found in the CCSM2/T31x3a control run are identified as “typical problems ” in global climate modelling. Finally, examples (simulation of North Atlantic hydrography, West African monsoon) are shown in which CCSM2/T31x3a has a better simulation skill than the latest low-resolution Community Climate System Model release, CCSM3/T31.