67 citations · 93 across the 9 of their papers we have counts for
12 papers
Toward a Universal Framework for the Internal Gravity Wave Spectrum
Leticia Fabre-Lima, Jeffrey Early, Miles A. Sundermeyer
The Garrett-Munk (GM) spectrum has long provided a canonical model of the oceanic internal gravity wave field. However, it relies on hydrostatic assumptions and idealized stratific…
Available potential vorticity and the wave-vortex decomposition for arbitrary stratification
Jeffrey J. Early, Gerardo Hernández-Dueñas, Leslie M. Smith +1
We consider a rotating non-hydrostatic flow with arbitrary stratification and argue that 1) the appropriate form of potential vorticity (PV) for this system is in terms of isopycna…
Integral theorems for the gradient of a vector field, with a fluid dynamical application
Jonathan M. Lilly, Joel Feske, Baylor Fox-Kemper +1
The familiar divergence and Kelvin-Stokes theorem are generalized by a tensor-valued identity that relates the volume integral of the gradient of a vector field to the integral ove…
Exact expressions for available potential energy and available potential vorticity
Jeffrey J. Early, Gerardo Hernández-Dueñas, Leslie M. Smith +1
Exact analytical expressions for available potential energy density (APE) and available potential vorticity (APV) are derived from first principles. These APE and APV expressions a…
Separating Mesoscale and Submesoscale Flows from Clustered Drifter Trajectories
Sarah Oscroft, Adam M. Sykulski, Jeffrey J. Early
Drifters deployed in close proximity collectively provide a unique observational data set with which to separate mesoscale and submesoscale flows. In this paper we provide a princi…
A generalized wave-vortex decomposition for rotating Boussinesq flows with arbitrary stratification
Jeffrey J. Early, M. Pascale Lelong, Miles A. Sundermeyer
The linear wave and geostrophic (vortex) solutions are shown to be a complete basis for physical variables in a rotating non-hydrostatic Boussinesq model with arbitrary…
Smoothing and Interpolating Noisy GPS Data with Smoothing Splines
Jeffrey J. Early, Adam M. Sykulski
A comprehensive methodology is provided for smoothing noisy, irregularly sampled data with non-Gaussian noise using smoothing splines. We demonstrate how the spline order and tensi…
Analysis of nonstationary modulated time series with applications to oceanographic flow measurements
Arthur P. Guillaumin, Adam M. Sykulski, Sofia C. Olhede +2
We propose a new class of univariate nonstationary time series models, using the framework of modulated time series, which is appropriate for the analysis of rapidly-evolving time…
The De-Biased Whittle Likelihood
Adam M. Sykulski, Sofia C. Olhede, Arthur P. Guillaumin +2
The Whittle likelihood is a widely used and computationally efficient pseudo-likelihood. However, it is known to produce biased parameter estimates for large classes of models. We…
Fractional Brownian motion, the Matern process, and stochastic modeling of turbulent dispersion
J. M. Lilly, A. M. Sykulski, J. J Early +1
Stochastic process exhibiting power-law slopes in the frequency domain are frequently well modeled by fractional Brownian motion (fBm). In particular, the spectral slope at high fr…
A Power Variance Test for Nonstationarity in Complex-Valued Signals
Thomas E. Bartlett, Adam M. Sykulski, Sofia C. Olhede +2
We propose a novel algorithm for testing the hypothesis of nonstationarity in complex-valued signals. The implementation uses both the bootstrap and the Fast Fourier Transform such…
Frequency-Domain Stochastic Modeling of Stationary Bivariate or Complex-Valued Signals
Adam M. Sykulski, Sofia C. Olhede, Jonathan M. Lilly +1
There are three equivalent ways of representing two jointly observed real-valued signals: as a bivariate vector signal, as a single complex-valued signal, or as two analytic signal…