References of "Nonlinear Processes in Geophysics"
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See detailA statistical validation for the cycles found in air temperature data using a Morlet wavelet-based method
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

in Nonlinear Processes in Geophysics (2010), 17

Recently, new cycles, associated with periods of 30 and 43 months, respectively, have been observed by the authors in surface air temperature time series, using a wavelet-based methodology. Although many ... [more ▼]

Recently, new cycles, associated with periods of 30 and 43 months, respectively, have been observed by the authors in surface air temperature time series, using a wavelet-based methodology. Although many evidences attest the validity of this method applied to climatic data, no systematic study of its efficiency has been carried out. Here, we estimate confidence levels for this approach and show that the observed cycles are significant. Taking these cycles into consideration should prove helpful in increasing the accuracy of the climate model projections of climate change and weather forecast. [less ▲]

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See detailWhistler oscillitons revisited: the role of charge neutrality?
Verheest, F.; Cattaert, Tom ULg; Dubinin, E. et al

in Nonlinear Processes in Geophysics (2004), 11(4), 447-452

When studying transverse modes propagating parallel to a static magnetic field, an apparent contradiction arises between the weakly nonlinear results obtained from the derivative nonlinear Schrodinger ... [more ▼]

When studying transverse modes propagating parallel to a static magnetic field, an apparent contradiction arises between the weakly nonlinear results obtained from the derivative nonlinear Schrodinger equation, predicting envelope solitons (where the amplitude is stationary in the wave frame, but the phase is not), and recent results for whistler oscillitons, indicating that really stationary structures of large amplitude are possible. Revisiting this problem in the fluid dynamic approach, care has been taken not to introduce charge neutrality from the outset, because this not only neglects electric stresses compared to magnetic stresses, which is reasonable, but could also imply from Poisson's equation a vanishing of the wave electric field. Nevertheless, the fixed points of the remaining equations are the same, whether charge neutrality is assumed from the outset or not, so that the solitary wave solutions at not too large amplitudes will be very similar. This is home out by numerical simulations of the solutions under the two hypotheses, showing that the lack of correspondence with the DNLS envelope solitons indicates the limitations of the reductive perturbation approach, and is not a consequence of assuming charge neutrality. [less ▲]

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