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Jun 30, 2018
06/18

by
Ana Russo; Pedro G. Lind; Frank Raischel; Ricardo Trigo; Manuel Mendes

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We present a simple framework to easily pre-select the most essential data for accurately forecasting the concentration of the pollutant PM$_{10}$, based on pollutants observations for the years 2002 until 2006 in the metropolitan region of Lisbon, Portugal. Starting from a broad panoply of different data sets collected at several meteorological stations, we apply a forward stepwise regression procedure that enables us not only to identify the most important variables for forecasting the...

Topics: Physics, Data Analysis, Statistics and Probability, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1411.0701

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1.0

Jun 30, 2018
06/18

by
Jacob Haqq-Misra

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Climate variability over the past million years shows a strong glacial-interglacial cycle of ~100,000 years as a combined result of Milankovitch orbital forcing and climatic resonance. It has been suggested that anthropogenic contributions to radiative forcing may extend the length of the present interglacial, but the effects of anthropogenic forcing on the periodicity of glacial-interglacial cycles has received little attention. Here I demonstrate that moderate anthropogenic forcing can act to...

Topics: Physics, Earth and Planetary Astrophysics, Atmospheric and Oceanic Physics, Astrophysics

Source: http://arxiv.org/abs/1406.4728

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Jun 30, 2018
06/18

by
Rosangela S. Cintra; Haroldo F. de Campos Velho

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This paper presents an approach for employing artificial neural networks (NN) to emulate an ensemble Kalman filter (EnKF) as a method of data assimilation. The assimilation methods are tested in the Simplified Parameterizations PrimitivE-Equation Dynamics (SPEEDY) model, an atmospheric general circulation model (AGCM), using synthetic observational data simulating localization of balloon soundings. For the data assimilation scheme, the supervised NN, the multilayer perceptrons (MLP-NN), is...

Topics: Physics, Computing Research Repository, Atmospheric and Oceanic Physics, Artificial Intelligence

Source: http://arxiv.org/abs/1407.4360

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Jun 28, 2018
06/18

by
D. Pazó; A. Carrassi; J. M. López

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A new nudging method for data assimilation, delay-coordinate nudging, is presented. Delay-coordinate nudging makes explicit use of present and past observations in the formulation of the forcing driving the model evolution at each time-step. Numerical experiments with a low order chaotic system show that the new method systematically outperforms standard nudging in different model and observational scenarios, also when using an un-optimized formulation of the delay-nudging coefficients. A...

Topics: Nonlinear Sciences, Atmospheric and Oceanic Physics, Chaotic Dynamics, Physics

Source: http://arxiv.org/abs/1510.07884

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Jun 30, 2018
06/18

by
Anna Deluca; Nicholas R. Moloney; Alvaro Corral

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We study the occurrence of events, subject to threshold, in a representative SOC sandpile model and in high-resolution rainfall data. The predictability in both systems is analyzed by means of a decision variable sensitive to event clustering, and the quality of the predictions is evaluated by the receiver operating characteristics (ROC) method. In the case of the SOC sandpile model, the scaling of quiet-time distributions with increasing threshold leads to increased predictability of extreme...

Topics: Physics, Data Analysis, Statistics and Probability, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1411.2256

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3.0

Jun 28, 2018
06/18

by
Darin Comeau; Zhizhen Zhao; Dimitrios Giannakis; Andrew J. Majda

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The North Pacific exhibits patterns of low-frequency variability on the intra-annual to decadal time scales, which manifest themselves in both model data and the observational record, and prediction of such low-frequency modes of variability is of great interest to the community. While parametric models, such as stationary and non-stationary autoregressive models, possibly including external factors, may perform well in a data-fitting setting, they may perform poorly in a prediction setting....

Topics: Data Analysis, Statistics and Probability, Atmospheric and Oceanic Physics, Mathematics, Numerical...

Source: http://arxiv.org/abs/1509.05332

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Jun 28, 2018
06/18

by
Ehud Strobach; Golan Bel

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Ensembles of climate models are commonly used to improve climate predictions and assess the uncertainties associated with them. Weighting the models according to their performances holds the promise of further improving their predictions. Here, we use an ensemble of decadal climate predictions to demonstrate the ability of sequential learning algorithms (SLAs) to reduce the forecast errors and reduce the uncertainties. Three different SLAs are considered, and their performances are compared...

Topics: Statistics, Data Analysis, Statistics and Probability, Atmospheric and Oceanic Physics, Machine...

Source: http://arxiv.org/abs/1509.05285

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Jun 29, 2018
06/18

by
Dominik Traxl; Niklas Boers; Jürgen Kurths

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Network theory has proven to be a powerful tool in describing and analyzing systems by modelling the relations between their constituent objects. In recent years great progress has been made by augmenting `traditional' network theory. However, existing network representations still lack crucial features in order to serve as a general data analysis tool. These include, most importantly, an explicit association of information with possibly heterogeneous types of objects and relations, and a...

Topics: Social and Information Networks, Atmospheric and Oceanic Physics, Data Analysis, Statistics and...

Source: http://arxiv.org/abs/1604.00971

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Jun 30, 2018
06/18

by
Qing Yi Feng; Jan P. Viebahn; Henk A. Dijkstra

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The Atlantic Meridional Overturning Circulation (MOC) is a crucial part of the climate system because of its associated northward heat transport. The present-day MOC is sensitive to freshwater anomalies and may collapse to a state with a strongly reduced northward heat transport. A future collapse of the Atlantic MOC has been identified as one of the most dangerous tipping points in the climate system. It is therefore crucial to develop early warning indicators for such a potential collapse...

Topics: Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1405.1315

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Jun 30, 2018
06/18

by
I. M. Mindlin

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Nonlinear initial-boundary value problem on deep-water gravity waves of finite amplitude is solved approximately (up to small terms of higher order) assuming that the waves are generated by an initial disturbance to the water and the horizontal dimensions of the initially disturbed body of the water are much larger than the magnitude of the free surface displacement. A numerable set of specific free surface waves is obtained in closed form and it is shown that free surface waves produced by an...

Topics: Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1406.1681

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Jun 30, 2018
06/18

by
Ilia M. Mindlin

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This paper addresses deep-water gravity waves of finite amplitude generated by an initial disturbance to the water. It is assumed that the horizontal dimensions of the initially disturbed body of the water are much larger than the magnitude of the free surface displacement in the origin of the waves. Initially the free surface has not yet been displaced from its equilibrium position, but the velocity field has already become different from zero. This means that the water at rest initially is...

Topics: Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1408.4398

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Jun 30, 2018
06/18

by
Juan Zanella; Ezequiel Alvarez; Andres Pescio; Walter Dragani

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A possible deepening of the ocean mixed layer was investigated at a selected point of the Patagonian continental shelf where a significant positive wind speed trend was estimated. Using a 1-dimensional vertical numerical model (S2P3) forced by atmospheric data from NCEP/NCAR I reanalysis and tidal constituents from TPXO 7.2 global model on a long term simulation (1979-2011), it was found that the mixed layer thickness presents a significant and positive trend of 10.1 +/- 1.4 cm/yr. Several...

Topics: Physics, Atmospheric and Oceanic Physics, Geophysics

Source: http://arxiv.org/abs/1405.1474

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Jun 30, 2018
06/18

by
Pascal Marquet

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A moist entropy potential temperature -- denoted by ${\theta}_{s}$ -- is defined analytically in terms of the specific entropy for moist air. The expression for ${\theta}_{s}$ is valid for a general mixing of dry air, water vapour and possible condensed water species. It verifies the same conservative properties as the moist entropy, even for varying dry air or total water content. The moist formulation for ${\theta}_{s}$ is equal to the dry formulation $\theta$ if dry air is considered and it...

Topics: Physics, Fluid Dynamics, Atmospheric and Oceanic Physics, Geophysics

Source: http://arxiv.org/abs/1401.1097

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Jun 27, 2018
06/18

by
Pascal Marquet

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Uncertainty exists concerning the proper formulation of surface heat fluxes, namely the sum of "sensible" and "latent" heat fluxes, and in fact concerning these two fluxes if they are considered as separate fluxes. In fact, eddy flux of moist-air energy must be defined as the eddy transfer of moist-air specific enthalpy ($\overline{w' h'}$), where the specific enthalpy ($h$) is equal to the internal energy of moist air plus the pressure divided by the density (namely $h =...

Topics: Atmospheric and Oceanic Physics, Fluid Dynamics, Geophysics, Physics

Source: http://arxiv.org/abs/1503.01649

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Jun 30, 2018
06/18

by
Jacques Vanneste

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Oceanic near-inertial waves - internal waves with frequencies close to the local Coriolis frequency $f_0$ - are strongly influenced by the presence of mean currents. To study this influence, Young and Ben Jelloul (1997) derived an asymptotic model that describes the slow modulation of the amplitude of these waves about their rapid oscillation at frequency $f_0$. Here we show that this model can be obtained within a variational framework, by (Whitham) averaging the Lagrangian of the...

Topics: Physics, Fluid Dynamics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1410.0253

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Jun 28, 2018
06/18

by
Mahdi Esmaily-Moghadam; Ali Mani

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An asymptotic solution is derived for the motion of inertial particles exposed to Stokes drag in an unsteady random flow. This solution provides the finite-time Lyapunov exponents as a function of Stokes number and Lagrangian strain- and rotation-rates autocovariances. The sum of these exponents, which corresponds to a concentration-weighted divergence of particle velocity field, is considered as a measure of clustering. For inertial particles dispersed in an isotropic turbulent flow our...

Topics: Fluid Dynamics, Atmospheric and Oceanic Physics, Physics

Source: http://arxiv.org/abs/1510.00776

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Jun 30, 2018
06/18

by
Jakob Runge; Dino Sejdinovic; Seth Flaxman

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Detecting causal associations in time series datasets is a key challenge for novel insights into complex dynamical systems such as the Earth system or the human brain. Interactions in high-dimensional dynamical systems often involve time-delays, nonlinearity, and strong autocorrelations. These present major challenges for causal discovery techniques such as Granger causality leading to low detection power, biases, and unreliable hypothesis tests. Here we introduce a reliable and fast method...

Topics: Physics, Statistics, Applications, Methodology, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1702.07007

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1.0

Jun 29, 2018
06/18

by
Soumyabrata Dev; Shilpa Manandhar; Yee Hui Lee; Stefan Winkler

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Ground-based sky cameras (popularly known as Whole Sky Imagers) are increasingly used now-a-days for continuous monitoring of the atmosphere. These imagers have higher temporal and spatial resolutions compared to conventional satellite images. In this paper, we use ground-based sky cameras to detect the onset of rainfall. These images contain additional information about cloud coverage and movement and are therefore useful for accurate rainfall nowcast. We validate our results using rain gauge...

Topics: Physics, Computer Vision and Pattern Recognition, Computing Research Repository, Atmospheric and...

Source: http://arxiv.org/abs/1610.06667

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3.0

Jun 27, 2018
06/18

by
Alberto Carrassi; Stéphane Vannitsem

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This chapter describes a novel approach for the treatment of model error in geophysical data assimilation. In this method, model error is treated as a deterministic process fully correlated in time. This allows for the derivation of the evolution equations for the relevant moments of the model error statistics required in data assimilation procedures, along with an approximation suitable for application to large numerical models typical of environmental science. In this contribution we first...

Topics: Atmospheric and Oceanic Physics, Physics

Source: http://arxiv.org/abs/1503.00842

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3.0

Jun 30, 2018
06/18

by
Donald B. Percival; Donald W. Denbo; Marie C. Eble; Edison Gica; Paul Y. Huang; Harold O. Mofjeld; Michael C. Spillane; Vasily V. Titov; Elena I. Tolkova

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U.S. Tsunami Warning Centers use real-time bottom pressure (BP) data transmitted from a network of buoys deployed in the Pacific and Atlantic Oceans to tune source coefficients of tsunami forecast models. For accurate coefficients and therefore forecasts, tides at the buoys must be accounted for. In this study, five methods for coefficient estimation are compared, each of which accounts for tides differently. The first three subtract off a tidal prediction based on (1) a localized harmonic...

Topics: Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1403.0528

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0.0

Jun 30, 2018
06/18

by
M. Abuladze; Z. Osmanov

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In this paper we consider the role of nonmodal instabilities in the dynamics of atmospheric tornadoes. For this purpose we consider the Euler equation, continuity equation and the equation of state and linearise them. As an example we study several different velocity profiles: the so-called Rankine vortex model; the Burgers-Rott vortex model; Sullivan and modified Sullivan vortex models. It has been shown that in the two dimensional Rankine vortex model no instability appears in the inner...

Topics: Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1703.07254

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Jun 29, 2018
06/18

by
Michael Bianco; Peter Gerstoft

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To provide constraints on their inversion, ocean sound speed profiles (SSPs) often are modeled using empirical orthogonal functions (EOFs). However, this regularization, which uses the leading order EOFs with a minimum-energy constraint on their coefficients, often yields low resolution SSP estimates. In this paper, it is shown that dictionary learning, a form of unsupervised machine learning, can improve SSP resolution by generating a dictionary of shape functions for sparse processing (e.g....

Topics: Atmospheric and Oceanic Physics, Data Analysis, Statistics and Probability, Physics, Mathematics,...

Source: http://arxiv.org/abs/1609.04840

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Jun 30, 2018
06/18

by
Marc Wiedermann; Jonatan F. Siegmund; Jonathan F. Donges; Jürgen Kurths; Reik V. Donner

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The specific impacts of El Ni\~no's two flavors, East Pacific (EP) and Central Pacific (CP) El Ni\~no, have been studied intensively in recent years, mostly by applying linear statistical or composite analyses. These techniques, however, focus on average spatio-temporal patterns of climate variability and do not allow for a specific assessment of related extreme impacts. Here, we use event coincidence analysis to study the differential imprints of EP and CP types of both, El Ni\~no and La...

Topics: Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1702.00218

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1.0

Jun 29, 2018
06/18

by
James Walsh

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M. Budyko and W. Sellers independently introduced seminal energy balance climate models in 1969, each with a goal of investigating the role played by positive ice albedo feedback in climate dynamics. In this paper we replace the relaxation to the mean horizontal heat transport mechanism used in the models of Budyko and Sellers with diffusive heat transport. We couple the resulting surface temperature equation with an equation for movement of the edge of the ice sheet (called the ice line),...

Topics: Physics, Dynamical Systems, Atmospheric and Oceanic Physics, Mathematics

Source: http://arxiv.org/abs/1607.07769

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1.0

Jun 26, 2018
06/18

by
Vladimir E. Zakharov

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We offer a new form for the S(nl) term in the Hasselmann kinetic equation for squared wave amplitudes of wind-driven gravity wave. This form of S(nl) makes possible to rewrite in differential form the conservation laws for energy, momentum, and wave action, and introduce their fluxes by a natural way. We show that the stationary kinetic equation has a family of exact Kolmogorov-type solutions governed by the fluxes of motion constants: wave action, energy, and momentum. The simple...

Topics: Atmospheric and Oceanic Physics, Physics, Fluid Dynamics

Source: http://arxiv.org/abs/1502.02628

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Jun 30, 2018
06/18

by
Douglas G. Dommermuth; Christopher D. Lewis; Vu H. Tran; Miguel A. Valenciano

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A formulation is developed to assimilate ocean-wave data into the Numerical Flow Analysis (NFA) code. NFA is a Cartesian-based implicit Large-Eddy Simulation (LES) code with Volume of Fluid (VOF) interface capturing. The sequential assimilation of data into NFA permits detailed analysis of ocean-wave physics with higher bandwidths than is possible using either other formulations, such as High-Order Spectral (HOS) methods, or field measurements. A framework is provided for assimilating the wavy...

Topics: Physics, Fluid Dynamics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1410.0418

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Jun 30, 2018
06/18

by
J. B. Marston; Wanming Qi; S. M. Tobias

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We review progress that has been made in utilizing one form of Direct Statistical Simulation (DSS) to describe geophysical and astrophysical flows that are anisotropic and inhomogeneous. We first explain the approach, which is based upon a systematic and conservative expansion of the equations of motion for low-order equal-time cumulants. We place the method into context with other statistical procedures. Truncation at second order in the hierarchy of cumulants is equivalent to retaining the...

Topics: Fluid Dynamics, Physics, Earth and Planetary Astrophysics, Atmospheric and Oceanic Physics,...

Source: http://arxiv.org/abs/1412.0381

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2.0

Jun 27, 2018
06/18

by
Thomas Pähtz; Amir Omeradžić; Marcus V. Carneiro; Nuno A. M. Araújo; Hans J. Herrmann

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The saturation length of aeolian sand transport ($L_s$), characterizing the distance needed by wind-blown sand to adapt to changes in the wind shear, is essential for accurate modeling of the morphodynamics of Earth's sandy landscapes and for explaining the formation and shape of sand dunes. In the last decade, it has become a widely-accepted hypothesis that $L_s$ is proportional to the characteristic distance needed by transported particles to reach the wind speed (the ``drag length''). Here...

Topics: Condensed Matter, Atmospheric and Oceanic Physics, Soft Condensed Matter, Geophysics, Computational...

Source: http://arxiv.org/abs/1503.03946

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2.0

Jun 30, 2018
06/18

by
Nicola Scafetta

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During the last few years a number of works have proposed that planetary harmonics regulate solar oscillations and the Earth climate. Herein I address some critiques. Detailed analysis of the data do support the planetary theory of solar and climate variation. In particular, I show that: (1) high-resolution cosmogenic 10Be and 14C solar activity proxy records both during the Holocene and during the Marine Interglacial Stage 9.3 (MIS 9.3), 325-336 kyr ago, present four common spectral peaks at...

Topics: Physics, Astrophysics, Atmospheric and Oceanic Physics, Earth and Planetary Astrophysics,...

Source: http://arxiv.org/abs/1412.0250

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1.0

Jun 30, 2018
06/18

by
Luigi Carlo Berselli; Matteo Cerminara; Traian Iliescu

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In this paper we study the motion of a fluid with several dispersed particles whose concentration is very small (smaller than $10^{-3}$), with possible applications to problems coming from geophysics, meteorology, and oceanography. We consider a very dilute suspension of heavy particles in a quasi-incompressible fluid (low Mach number). In our case the Stokes number is small and --as pointed out in the theory of multiphase turbulence-- we can use an Eulerian model instead of a Lagrangian one....

Topics: Physics, Fluid Dynamics, Mathematics, Atmospheric and Oceanic Physics, Analysis of PDEs,...

Source: http://arxiv.org/abs/1403.5448

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Jun 29, 2018
06/18

by
W. Steven Rosenthal; Shankar C. Venkataramani; Arthur J. Mariano; Juan M. Restrepo

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We show that modifying a Bayesian data assimilation scheme by incorporating kinematically-consistent displacement corrections produces a scheme that is demonstrably better at estimating partially observed state vectors in a setting where feature information important. While the displacement transformation is not tied to any particular assimilation scheme, here we implement it within an ensemble Kalman Filter and demonstrate its effectiveness in tracking stochastically perturbed vortices.

Topics: Data Analysis, Statistics and Probability, Physics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1602.02209

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1.0

Jun 30, 2018
06/18

by
F. J. Beron-Vera; M. J. Olascoaga; G. Haller; M. Farazmand; J. Trinanes; Y. Wang

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Recent developments in dynamical systems theory have revealed long-lived and coherent Lagrangian (i.e., material) eddies in incompressible, satellite-derived surface ocean velocity fields. Paradoxically, observed drifting buoys and floating matter tend to create dissipative-looking patterns near oceanic eddies, which appear to be inconsistent with the conservative fluid particle patterns created by coherent Lagrangian eddies. Here we show that inclusion of inertial effects (i.e., those produced...

Topics: Physics, Nonlinear Sciences, Fluid Dynamics, Chaotic Dynamics, Mathematics, Atmospheric and Oceanic...

Source: http://arxiv.org/abs/1408.6512

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Jun 29, 2018
06/18

by
Kasper W Olsen; Jakob Bohr

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A simple phenomenological account for planetary climate instabilities is presented. The description is based on the standard model where the balance of incoming stellar radiation and outward thermal radiation is described by the effective planet temperature. Often, it is found to have three different points, or temperatures, where the influx of radiation is balanced with the out-flux, even with conserved boundary conditions. Two of these points are relatively long-term stable, namely the point...

Topics: Earth and Planetary Astrophysics, Astrophysics, Atmospheric and Oceanic Physics, Physics

Source: http://arxiv.org/abs/1605.08471

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2.0

Jun 27, 2018
06/18

by
Yong Zou; Elbert E. N. Macau; Gilvan Sampaio; Antônio Mário; Jürgen Kurths

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We propose a new measure based on drought period length to assess the temporal difference between the recent two severe droughts of 2005 and 2010 in the Amazonia. The sensitivity of the measure is demonstrated by disclosing the distinct spatial responding mechanisms of the Northeastern and Southwestern Amazon (NA, SA) to the surrounding sea surface temperature (SST) variabilities. The Pacific and Atlantic oceans have different roles on the precipitation patterns in Amazonia. More specifically,...

Topics: Atmospheric and Oceanic Physics, Physics

Source: http://arxiv.org/abs/1506.03532

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Jun 26, 2018
06/18

by
Enrico Ser-Giacomi; Ruggero Vasile; Irene Recuerda; Emilio Hernández-García; Cristóbal López

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A Lagrangian flow network is constructed for the atmospheric blocking of eastern Europe and western Russia in summer 2010. We compute the most probable paths followed by fluid particles which reveal the {\it Omega}-block skeleton of the event. A hierarchy of sets of highly probable paths is introduced to describe transport pathways when the most probable path alone is not representative enough. These sets of paths have the shape of narrow coherent tubes flowing close to the most probable one....

Topics: Physics, Statistical Mechanics, Atmospheric and Oceanic Physics, Condensed Matter

Source: http://arxiv.org/abs/1501.04516

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Jun 30, 2018
06/18

by
Tanja Zerenner; Victor Venema; Petra Friederichs; Clemens Simmer

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The coupling of models for the different components of the Soil-Vegetation-Atmosphere-System is required to investigate component interactions and feedback processes. However, the component models for atmosphere, land-surface and subsurface are usually operated at different resolutions in space and time owing to the dominant processes. The computationally often more expensive atmospheric models, for instance, are typically employed at a coarser resolution than land-surface and subsurface...

Topics: Physics, Neural and Evolutionary Computing, Atmospheric and Oceanic Physics, Computing Research...

Source: http://arxiv.org/abs/1407.1768

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1.0

Jun 30, 2018
06/18

by
G. Lee; Ch. Helling; H. Giles; S. T. Bromley

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Clouds form in atmospheres of brown dwarfs and planets. The cloud particle formation processes are similar to the dust formation process studied in circumstellar shells of AGB stars and in Supernovae. Cloud formation modelling in substellar objects requires gravitational settling and element replenishment in addition to element depletion. All processes depend on the local conditions, and a simultaneous treatment is required. We apply new material data in order to assess our cloud formation...

Topics: Physics, Astrophysics, Atmospheric and Oceanic Physics, Atomic and Molecular Clusters,...

Source: http://arxiv.org/abs/1410.6610

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Jun 26, 2018
06/18

by
Henk Dijkstra; Taylan Sengul; Jie Shen; Shouhong Wang

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The main aim of this paper is to describe the dynamic transitions in flows described by the two-dimensional, barotropic vorticity equation in a periodic zonal channel. In \cite{CGSW03}, the existence of a Hopf bifurcation in this model as the Reynolds number crosses a critical value was proven. In this paper, we extend the results in \cite{CGSW03} by addressing the stability problem of the bifurcated periodic solutions. Our main result is the explicit expression of a non-dimensional number...

Topics: Atmospheric and Oceanic Physics, Physics, Fluid Dynamics

Source: http://arxiv.org/abs/1502.04974

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1.0

Jun 28, 2018
06/18

by
Sebastian Schubert; Valerio Lucarini

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One of the most relevant weather regimes in the mid-latitudes atmosphere is the persistent deviation from the approximately zonally symmetric jet to the emergence of blocking patterns. Such configurations are usually connected to exceptional local stability properties of the flow which come along with an improved local forecast skills during the phenomenon. It is instead extremely hard to predict onset and decay of blockings. Covariant Lyapunov Vectors (CLVs) offer a suitable characterization...

Topics: Atmospheric and Oceanic Physics, Geophysics, Nonlinear Sciences, Physics, Chaotic Dynamics, Fluid...

Source: http://arxiv.org/abs/1508.04002

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Jun 29, 2018
06/18

by
Raymond T. Pierrehumbert; Feng Ding

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The diversity of characteristics for the host of recently discovered exoplanets opens up a great deal of fertile new territory for geophysical fluid dynamics, particularly when the fluid flow is coupled to novel thermodynamics, radiative transfer or chemistry. In this paper, we survey one of these new areas-the climate dynamics of atmospheres with a non-dilute condensible component, defined as the situation in which a condensible component of the atmosphere makes up a substantial fraction of...

Topics: Earth and Planetary Astrophysics, Astrophysics, Atmospheric and Oceanic Physics, Physics

Source: http://arxiv.org/abs/1608.03294

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Jun 30, 2018
06/18

by
Oleg I. Berngardt; G. V. Kotovich; S. Ya. Mikhailov; A. V. Podlesny

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According to the data of quasi-vertical sounding at Usolie-Tory path (midpoint - 52.3N, 103E, 120km distance), the dynamics of vertical structure of the midscale inhomogeneities of the plasma frequency was reconstructed. These irregularities are caused by Tohoku earthquake 11/03/2011 (38.3N, 142.4E). Observed horizontal velocities of propagation in the ionosphere and the spatial scales of the wave-like disturbance modes, generated by earthquakes, are calculated. As a result of numerical...

Topics: Physics, Geophysics, Atmospheric and Oceanic Physics

Source: http://arxiv.org/abs/1407.1488

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Jun 29, 2018
06/18

by
Jeffrey B. Parker

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The self-organization of turbulence into regular zonal flows can be fruitfully investigated with quasilinear methods and statistical descriptions. A wave kinetic equation that assumes asymptotically large-scale zonal flows is pathological. From an exact description of quasilinear dynamics emerges two better geometrical optics approximations. These involve not only the mean flow shear but also the second and third derivative of the mean flow. One approximation takes the form of a new wave...

Topics: Atmospheric and Oceanic Physics, Physics, Plasma Physics

Source: http://arxiv.org/abs/1604.06904