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Comments on "The Role of the Central Asian Mountains on the Midwinter Suppression of North Pacific Storminess" - Reply
We thank Chang and Lin for their thoughtful and
constructive comments on our study (Park et al. 2010).
In Park et al. (2010), we did not explicitly state that the
topography-forced stationary waves are the direct cause
for the reduced downstream transient eddy kinetic energy
(EKE). The response of stationary waves to topography
may saturate even with a relatively small mountain (Cook
and Held 1992); furthermore, their magnitudes are much
smaller than thermally forced stationary waves (Chang
2009; Held et al. 2002). Instead, we suggest that quasistationary waves generated by the central Asian mountains may strongly affect North Pacific storminess by
changing the year-to-year variability of westerly winds
over the eastern Eurasian continent. Observational analyses
indicate that the midwinter suppression of North
Pacific storminess does not occur every year. Some years
experience stronger and more meridionally confined
zonal winds over the western North Pacific, leading to
stronger midwinter suppression (Harnik and Chang
2004; Nakamura and Sampe 2002)
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노트 : The authors acknowledge a support from the SSK (Social Science Korea) Program funded by National Research Foundation of South Korea; NRF-2010-330-B00232
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