2,083 research outputs found
SLIDES: Research on Ground Water Monitoring
Presenter: Matt Samelson, Natural Resources Law Center and the Donnell-Kay Foundation
12 slide
Lyapunov, Floquet, and singular vectors for baroclinic waves
The dynamics of the growth of linear disturbances to a chaotic basic state is analyzed in an asymptotic model of weakly nonlinear, baroclinic wave-mean interaction. In this model, an ordinary differential equation for the wave amplitude is coupled to a partial differential equation for the zonal flow correction. The leading Lyapunov vector is nearly parallel to the leading Floquet vector <font face='Symbol'><i>f</i></font><sub>1</sub> of the lowest-order unstable periodic orbit over most of the attractor. Departures of the Lyapunov vector from this orientation are primarily rotations of the vector in an approximate tangent plane to the large-scale attractor structure. Exponential growth and decay rates of the Lyapunov vector during individual Poincaré section returns are an order of magnitude larger than the Lyapunov exponent <font face='Symbol'>l</font> ≈ 0.016. Relatively large deviations of the Lyapunov vector from parallel to <font face='Symbol'><i>f</i></font><sub>1</sub> are generally associated with relatively large transient decays. The transient growth and decay of the Lyapunov vector is well described by the transient growth and decay of the leading Floquet vectors of the set of unstable periodic orbits associated with the attractor. Each of these vectors is also nearly parallel to <font face='Symbol'><i>f</i></font><sub>1</sub>. The dynamical splitting of the complete sets of Floquet vectors for the higher-order cycles follows the previous results on the lowest-order cycle, with the vectors divided into wave-dynamical and decaying zonal flow modes. Singular vectors and singular values also generally follow this split. The primary difference between the leading Lyapunov and singular vectors is the contribution of decaying, inviscidly-damped wave-dynamical structures to the singular vectors
SLIDES: Research on Ground Water Monitoring
Presenter: Matt Samelson, Natural Resources Law Center and the Donnell-Kay Foundation
12 slide
EPIC processing toolbox users guide
A set of computer programs for data analysis is described and documented. The programs were developed to aid in the
processing of time-series data collected by the Upper Ocean Processes Group. These programs, or tools, utilize a platform
independent format known as the Network Common Data Format (netCDF). The format is further defined using a convention
known as EPIC which allows easy access to other plotting and manipulation tools available to the UOP group. The general
method for implementation of the toolbox is described. A reference section lists the available tools, as well as examples and
detailed descriptions of their usage and functionality. The toolbox has been tested and used extensively on both Sun and Silicon
Graphics Interface UNIX workstations.Funding was provided by the Office of Naval Research
under Contract No. N00014-90-J-1495
Surface-intensified Rossby waves over rough topography
Observations and numerical experiments that suggest that sea-floor roughness can enhance the ratio of thermocline to abyssal eddy kinetic energy, motivate the study of linear free wave modes in a two layer quasi-geostrophic model for several eases of idealized variable bottom topography. The foeus is on topography with horizontal seale comparable to that of the waves, that is, on rough small-amplitude topography. Surface-intensified modes are found to exist at frequencies greater than the flat-bottom baroclinic cut-off frequency. These modes exist for topography that varies in both one and two horizontal dimensions. An approximate bound indicates that the maximum frequency of the surface-intensified modes is greater than the baroclinic cut-off by a factor equal to the total fluid depth divided by the lower layer depth. For fixed topographic wavenumber, there is not a simple dependence of the degree of surface-intensification on topographic amplitude, but rather a resonant structure with peaks at certain topographic amplitudes. These modes may be resonantly excited by surface forcing
Turnaround United Methodist churches in the California-Nevada Annual Conference
https://place.asburyseminary.edu/ecommonsatsdissertations/1422/thumbnail.jp
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