We investigated the meridional circulation of photospheric faculae throughout cycle 19. Together with the rotation observed in a companion paper (Meunier et al. 1996), we were able to address the problem of the existence of the observed differential rotation. Themeridional circulation is characterized by a strong north-south asymmetry. The distribution of meridional circulation around the mean ...

Passive tracers are used in an o€-line version of the United Kingdom Fine Resolution Antarctic Model (FRAM) to highlight features of the circulation and provide information on the inter-ocean exchange of water masses. The use of passive tracers allows a picture to be built up of the deep circulation which is not readily apparent from examination of the velocity or density ®elds. Comparison of o...

[1] Because of its relevance for the global climate the Atlantic meridional overturning circulation (AMOC) has been a major research focus for many years. Yet the question of which physical mechanisms ultimately drive the AMOC, in the sense of providing its energy supply, remains a matter of controversy. Here we review both observational data and model results concerning the two main candidates...

with earlier studies, discussion and explanation of differences to other studies is one main point of criticism. Furthermore, the level of significance to test the results is insufficient, significance of results on the at least 95% confidence level should be shown. The results are not explained properly, many features in the results figures remain unexplained, many questions the reader will ha...

The paper describes the evaluation of organic species concentrations as simulated by an atmospheric chemistry general circulation model. Overall it is a nice paper that deserves publication in ACP although there is a need for more detailed discussions at some places as further discussed in the following. Also in some cases, the rationales for choosing (or omitting) some sensitivity simulations ...

We study how the solar magnetic field evolves from antisymmetric (dipolar) to symmetric (quadrupolar) state during the course of its 11-yr cycle. We show that based on equatorial symmetries of the induction equation, flux transport solar mean field dynamo models excite mostly the antisymmetric (dipolar) family whereas a decomposition of the solar magnetic field data reveals that both families s...

The seasonal time dependence of the tropospheric circulation response to polar stratospheric cooling in a simple atmospheric general circulation model is investigated. When the model is run without a seasonal cycle, polar stratospheric cooling induces a positive annular-mode response in the troposphere that takes a remarkably long time—several hundred days—to fully equilibrate. One is thus led ...