Flux correction: tests with a simple ocean-atmosphere model |
| |
| Authors: | J Egger |
| |
| Institution: | Meteorologisches Institut, Universit?t München, Theresienstr. 37, D-80333 Munich, Germany, DE
|
| |
| Abstract: | Flux correction schemes are used in order to suppress the drift of coupled ocean atmosphere models. This technique is tested
for a simple box model of the climate system. Two “perfect” models of the ocean and the atmosphere are available. These are
coupled to form an ocean-atmosphere model representing the true climate system. This climate system is simulated by a climate
model which is also constructed by coupling those two perfect models. This time, however, both models are run first separately
as models of the atmosphere and the ocean. In that case, “observations” from the climate system are prescribed at the ocean
surface in the uncoupled models. It is assumed that these observations are imperfect. A drift results, when these models are
coupled to form an ocean-atmosphere stimulation model. A flux adjustment scheme is implemented to remove this drift. It is
argued that the merits and shortcomings of the flux correction technique can be assessed more clearly this way than by coupling
imperfect models as is done normally. Sensitivity tests are performed where either radiation parameters are changed or a salt
anomaly is implanted. Model parameters are chosen such that the ocean has a thermally direct circulation in the unperturbed
climate state. It is found that the flux correction technique is performing satisfactorily as long as the imposed perturbations
are small enough so that the ocean circulation does not change its sense. If, however, the model climate is close to the transition
to an indirect circulation, then the flux correction technique is unreliable. The predictions of the coupled model with flux
correction may deviate substantially from the response of the climate system in that case.
Received: 4 December 1995/Accepted: 15 October 1996 |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
