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Ahmed Mahidjiba, Abdessamad Qaddouri, and Jean Côté

-dimensional scheme developed by Rančić (1992) , which is based first on the interpolation for getting the piecewise function and second on the conservative remapping from the original grid to the grid consisting of the departure points. Nair and Machenhauer (2002) have developed a fully two-dimensional scheme for advection on the sphere employing the 2D representation (quasi-biparabolic), without time splitting and applicable for Courant numbers larger than one provided the trajectory algorithm has converged

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Brian Mapes, Ralph Milliff, and Jan Morzel

). Little spatial offset is seen between the PW and IR central maxima. Divergence perturbation fields (third row) show surface wind convergence leading the PW increase and IR decrease by many hours. These are perturbations in the sense that a constant mean offset has been subtracted, equal to the larger-scale (10° × 10°, 48-h average) convergence. Offsets are listed in the figure captions, and full values are shown in the time series in Fig. 8 . Near lag 0, the sign of these mesoscale perturbations at

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Matthew E. Peters, Zhiming Kuang, and Christopher C. Walker

humidity and divergence from the 40-yr European Centre for Medium-Range Weather Forecasts Re-Analysis (ERA-40) pressure level archive averaged across the northern intertropical convergence zone (ITCZ) from 7.5° to 10°N. In the western Pacific (50°–180°), mean convergence extends from the surface up to 400 hPa while the eastern Pacific ITCZ is characterized by boundary layer convergence below 850 hPa and divergence above associated with a “shallow return flow” above the boundary layer ( Zhang et al

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Henrique Fuchs Bueno Repinaldo, Matilde Nicolini, and Yanina García Skabar

with a northwest mountains–central plain mesoscale flow regime due to the main orientation north–south of the Andes and Sierras de Córdoba. According to breeze theories a nocturnal anomalous convergence and a diurnal anomalous divergence are expected. The authors found a diurnal cycle in the total divergence field in the boundary layer over the plains (as an average over the whole domain and over the 15-day-long period), with nocturnal convergence and daytime divergence. Daytime divergence is

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Ian Folkins, S. Fueglistaler, G. Lesins, and T. Mitovski

calculated divergence profiles were downloaded from the Colorado State University (CSU) TOGA COARE Sounding Data Archive. The IFA was approximately 200 km in diameter. Its location is shown in Fig. 2 . The higher values of dynamical divergence between 10 and 16.5 km reflect deep convective outflow into the background atmosphere. The dynamical divergence is increasingly negative in the lower troposphere, presumably reflecting the midlevel convergence of the stratiform mode, as well as entrainment into

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P. C. Chu

used to showthat an off-ice and divergent wind field not only produces a dilation of the MIZ (as is generally thought), butalso generates a compaction of MIZ for some circumstances. An ice divergence-convergence criterion in theMIZ is found and used to help explain some features, such as ice edge bands, and the formation and maintenanceof polynyas and leads. The model contains three parts: a thermally fomed boundary layer air flow, a mechanically driven ice drift,and a reduced gravity ocean. The

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Yu Du and Guixing Chen

with the cold front, belongs to a kind of SLLJ ( Du et al. 2014 ). The simulated BLJ and SLLJ are both consistent with the results in Part I and FNL reanalysis ( Figs. 9c,f,i ), suggesting a good performance in the WRF modeling. We can use the high-resolution WRF output to assess the fine structures and evolution of double LLJs and their impacts. Usually, the entrance and exit of the LLJs are related to the horizontal divergence and convergence, respectively ( Hastenrath 1985 ; Chen et al. 2014

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Elizabeth A. Barnes and Dennis L. Hartmann

relationships. We further show that the eddy vorticity flux convergence at upper levels is important to sustaining the vorticity maximum against divergence. The divergence at upper levels can be thought of as part of the geostrophic adjustment to the vorticity convergence, and the vertical motion cools the column to maintain a vortex maximum in the presence of eddy heat convergences that would otherwise cause the vortex to weaken. The eddy vorticity flux convergences at upper levels thus contribute to

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Christopher A. Davis and Thomas J. Galarneau Jr.

from convective momentum transport is also possible, but quantification of this effect will not be attempted here. The other factor mitigating the loss of vorticity due to transport out of the box is the direct contribution to strengthening the low-level vortex from condensation heating, perhaps even at the expense of the midlevel circulation. Note that the divergence profile changed radically around 1000 UTC (near sunrise) to a pattern with lower tropospheric convergence and midtropospheric

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Charles E. Tilburg and Richard W. Garvine

and convergence. The effect of the buoyancy intrusions and wind stress on the overall divergence of the flow field is examined using multi-input systems cross-spectral analysis of observations collected from moored instruments on the inner shelf off the coast of New Jersey during the upwelling season of 1996. The study site and observations used in this investigation are described in section 2 . Section 3 contains a brief discussion of the dynamics responsible for variations in the alongshore

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