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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)
Wave Propagation in Lossy and Superconducting Circular Waveguides
We present an accurate approach to compute the attenuation of waves, propagating in circular waveguides with lossy and superconducting walls. A set of transcendental equation is developed by matching the fields at the surface of the wall with the electrical properties of the wall material. The propagation constant kz is found by numerically solving for the root of the equation. The complex conductivity of the superconductor is obtained from the Mattis-Bardeen equations. We have compared the loss of TE11 mode computed using our technique with that using the perturbation and Stratton’s methods. The results from the three methods agree very well at a reasonable range of frequencies above the cutoff. The curves, however, deviate below cutoff and at millimeter wave frequencies. We attribute the discrepancies to the dispersive effect and the presence of the longitudinal fields in a lossy waveguide. At frequencies below the gap, the superconducting waveguide exhibits lossless transmission behavior. Above the gap frequency, Cooper-pair breaking becomes dominant and the loss increases significantly
Monte-Carlo Simulation of Pulsed Laser Deposition
Using the Monte Carlo method, we have studied the pulsed laser deposition
process at the sub-monolayer regime. In our simulations, dissociation of an
atom from a cluster is incorporated. Our results indicate that the pulsed laser
deposition resembles molecular beam epitaxy at very low intensity, and that it
is characteristically different from molecular beam epitaxy at higher
intensity. We have also obtained the island size distributions. The scaling
function for the island size distribution for pulsed laser deposition is
different from that of molecular beam epitaxy.Comment: 15 pages, 8 figure
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