Reply KUAN -

Abstract

We very much welcome the comments on our paper (Xu and Randall 1999, hereafter XR99) by Tao, Shie, and Simpson (2001, hereafter TSS). TSS comment on some different results and interpretations between XR99 and Tao et al. (1999, hereafter T99). Using the Goddard cumulus ensemble (GCE) model, T99 produced different statistical equilibrium (SE) states by changing the specifications of domain-averaged wind profiles, which closely correspond to the cold and dry SE state obtained by Sui et al. (1994, hereafter S94) using the GCE model, and the warm and humid SE state obtained by Grabowski et al. (1996a, hereafter G96) with a different model, respectively. T99 concluded that the runs that produce a more humid–warmer climate are always associated with stronger surface evaporation and stronger large-scale forcings. XR99, on the other hand, imposed the total largescale advective forcings in their control runs [method 2 in TSS; called ‘‘revealed forcing’’ in Randall and Cripe (1999)] instead of those produced by an imposed large-scale ascent (method 1 in TSS). That is, the horizontal advective tendencies are included. XR99 were able to produce an SE state that is close to a climatological mean, while neither S94 nor G96 were able to do so. TSS criticize the forcing method used in XR99. We are going to argue that methods 1 and 2 each have merits and flaws. TSS also question an interpretation of the results of S94 offered by XR99, namely, that the weak surface wind (in S94) cannot increase the surface evaporation enough to compensate for the enhanced precipitation (due to larger vertical advection) so that less precipitable water remains in the column. TSS also question the interpretation of the relationship between precipitable water and column temperature simulated by the sensitivity tests in XR99. We think that there is no

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Cite this paper

@inproceedings{Xu2009ReplyK, title={Reply KUAN -}, author={Kuan-Man Xu and David A. Randall}, year={2009} }