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0.0
Jun 29, 2018
06/18
by
Vladimir Zakharov; Donald Resio; Andrei Pushkarev
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The new ZRP wind input source term (Zakharov et al. 2012) is checked for its consistency via numerical simulation of Hasselmann equation. The results are compared to field experimental data, collected at different sites around the world, and theoretical predictions of self-similarity analysis. Good agreement is obtained for limited fetch and time domain statements
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1608.03790
0
0.0
Jun 30, 2018
06/18
by
Ehud Strobach; Golan Bel
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Meaningful climate predictions must be accompanied by their corresponding range of uncertainty. Quantifying the uncertainties is non-trivial, and different methods have been suggested and used in the past. Here, we propose a method that does not rely on any assumptions regarding the distribution of the ensemble member predictions. The method is tested using the CMIP5 1981-2010 decadal predictions and is shown to perform better than two other methods considered here. The improved estimate of the...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1701.05988
1
1.0
Jun 30, 2018
06/18
by
K. W. Bowman; J. Liu; A. A. Bloom; N. C. Parazoo; M. Lee; Z. Jiang; D. Menemenlis; M. M. Gierach; G. J. Collatz; K. R. Gurney; D. Wunch
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The El Ni\~{n}o Modoki in 2010 lead to historic droughts in Brazil. We quantify the global and Brazilian carbon response to this event using the NASA Carbon Monitoring System Flux (CMS-Flux) framework. Satellite observations of CO$_2$, CO, and solar induced fluorescence (SIF) are ingested into a 4D-variational assimilation system driven by carbon cycle models to infer spatially resolved carbon fluxes including net ecosystem exchange, biomass burning, and gross primary productivity (GPP). The...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1703.03778
0
0.0
Jun 29, 2018
06/18
by
E. Frajka-Williams; M. Lankhorst; J. Koelling; U. Send
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In situ boundary arrays have been installed in the North Atlantic to measure the large-scale ocean circulation. Here, we use measurements at the western edge of the North Atlantic at $16^\circ$N and $26^\circ$N to investigate low-frequency variations in deep densities and their associated influence on ocean transports. At both latitudes, deep waters (below 1100 dbar) at the western boundary are becoming fresher and less dense. The associated change in geopotential thickness is about $0.15$...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1610.06708
0
0.0
Jun 29, 2018
06/18
by
Juan Simarro; Petra Smolikova; Jozef Vivoda
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An analytical linear solution of the fully compressible Euler equations is found, in the particular case of a stationary two dimensional flow that passes over an orographic feature with small height-width ratio. A method based on the covariant formulation of the Euler equations is used, and the analytical vertical velocity as well as the horizontal velocity, density and pressure, are obtained. The analytical solution is tested against a numerical model in three different regimes, hydrostatic,...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1612.05673
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0.0
Jun 29, 2018
06/18
by
Laura Fierce; Robert L. McGraw
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Sparse representations of atmospheric aerosols are needed for efficient regional- and global-scale chemical transport models. Here we introduce a new framework for representing aerosol distributions, based on the quadrature method of moments. Given a set of moment constraints, we show how linear programming, combined with an entropy-inspired cost function, can be used to construct optimized quadrature representations of aerosol distributions. The sparse representations derived from this...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1612.06422
0
0.0
Jun 29, 2018
06/18
by
M. M. P. van Hulten; R. Middag; J. -C. Dutay; H. J. W. de Baar; M. Roy-Barman; M. Gehlen; A. Tagliabue; A. Sterl
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Dissolved manganese (Mn) is a biologically essential element, and its oxidised form is involved in the removal of trace elements from ocean waters. Recently, a large number of highly accurate Mn measurements have been obtained in the Atlantic, Indian and Arctic Oceans as part of the GEOTRACES programme. The goal of this study is to combine these new observations with state-of-the-art modelling to give new insights into the main sources and redistribution of Mn throughout the ocean. To this end,...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1606.07128
2
2.0
Jun 27, 2018
06/18
by
F. J. Beron-Vera; J. H. LaCasce
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Pair-separation statistics of in-situ and synthetic surface drifters deployed near the \emph{Deepwater Horizon} site in the Gulf of Mexico are investigated. The synthetic trajectories derive from a 1-km-resolution data-assimilative Navy Coastal Ocean Model (NCOM) simulation. The in-situ drifters were launched in the Grand LAgrangian Deployment (GLAD). Diverse measures of the dispersion are calculated and compared to theoretical predictions. For the NCOM pairs, the measures indicate nonlocal...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1505.03475
0
0.0
Jun 30, 2018
06/18
by
Matthew Gruber; Javier Fochesatto; Oscar Hartogensis
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Displaced-beam scintillometer measurements of the turbulence inner-scale length $l_o$ and refractive index structure function $C_n^2$ resolve area-average turbulent fluxes of heat and momentum through the Monin-Obukhov similarity equations. Sensitivity studies have been produced for the use of displaced-beam scintillometers over flat terrain. Many real field sites feature variable topography. We develop here an analysis of the sensitivity of displaced-beam scintillometer derived sensible heat...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1405.2309
0
0.0
Jun 28, 2018
06/18
by
Zied Ben Bouallegue
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The assessment of the high-resolution ensemble weather prediction system COSMO-DE-EPS is achieved with the perspective of using it for renewable energy applications. The performance of the ensemble forecast is explored focusing on global radiation, the main weather variable affecting solar power production, and on quantile forecasts, key probabilistic products for the energy sector. First, the ability of the ensemble system to capture and resolve the observation variability is assessed....
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1510.00535
0
0.0
Jun 29, 2018
06/18
by
Øyvind Breivik; Jean-Raymond Bidlot; Peter A. E. M. Janssen
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A new approximation to the Stokes drift velocity profile based on the exact solution for the Phillips spectrum is explored. The profile is compared with the monochromatic profile and the recently proposed exponential integral profile. ERA-Interim spectra and spectra from a wave buoy in the central North Sea are used to investigate the behaviour of the profile. It is found that the new profile has a much stronger gradient near the surface and lower normalized deviation from the profile computed...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1601.08092
0
0.0
Jun 29, 2018
06/18
by
Lilly Verso; Maarten van Reeuwijk; Roi Gurka; Peter J. Diamessis; Zachary J. Taylor; Alex Liberzon
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We present a laboratory experiment of the growth of a turbulent patch in a stably stratified fluid, due to a localized source of turbulence, generated by an oscillating grid. Synchronized and overlapping particle image velocimetry and planar laser induced fluorescence measurements have been conducted capturing the evolution of the patch through its initial growth until it reached a maximum size, followed by its collapse. The simultaneous measurements of density and velocity fields allow for a...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1603.06516
0
0.0
Jun 28, 2018
06/18
by
Francesco Fedele
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An unexpected wave is defined by Gemmrich & Garrett (2008) as a wave that is much taller than a set of neighboring waves. Their definition of "unexpected" refers to a wave that is not anticipated by a casual observer. Clearly, unexpected waves defined in this way are predictable in a statistical sense. They can occur relatively often with a small or moderate crest height, but large unexpected waves that are rogue are rare. Here, this concept is elaborated and statistically...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1507.07873
1
1.0
Jun 30, 2018
06/18
by
F. Spineanu; M. Vlad; D. Palade
texts
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Large scale organization in ensembles of events of atmospheric convection can be generated by the combined effect of forcing and of the interaction between the raising plumes and the environment. Here the "large scale" refers to the space extension that is larger or comparable with the basic resolved cell of a numerical weather prediction system. Under the action of external forcing like heating individual events of convection respond to the slow accumulation of vapor by a...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1404.4538
0
0.0
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
0
0.0
Jun 28, 2018
06/18
by
David Collins; Boualem Khouider
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We propose a mathematical methodology to derive a stochastic parameterization of bulk warm cloud micro-physics properties. Unlike previous bulk parameterizations, the stochastic parameterization does not assume any particular droplet size distribution, all parameters have physical meanings which are recoverable from data, and the resultant parameterization has the flexibility to utilize a variety of collision kernels. Our strategy is a new two-fold approach to modelling the kinetic collection...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1512.08517
0
0.0
Jun 29, 2018
06/18
by
Cihan Bayindir; J. David Frost; Christopher F. Barnes
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In this study the detection of the oil spill using synthetic aperture radar (SAR) imagery is considered. Detection of the oil spill is performed using change detection algorithms between imagery acquired at different times. The specific algorithms used are the correlation coefficient change statistic and the intensity ratio change statistic algorithms. Therefore these algorithms and the probabilistic selection of the threshold criteria is reviewed and discussed. A recently offered change...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1604.00625
0
0.0
Jun 27, 2018
06/18
by
Matthieu J. Mercier; Louis Gostiaux; Karl Helfrich; Joël Sommeria; Samuel Viboud; Henri Didelle; Sasan Saidi; Thierry Dauxois; Thomas Peacock
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The complex double-ridge system in the Luzon Strait in the South China Sea (SCS) is one of the strongest sources of internal tides in the oceans, associated with which are some of the largest amplitude internal solitary waves on record. An issue of debate, however, has been the specific nature of their generation mechanism. To provide insight, we present the results of a large-scale laboratory experiment performed at the Coriolis platform. The experiment was carefully designed so that the...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1504.04193
0
0.0
Jun 30, 2018
06/18
by
M. V. Budyansky; V. A. Goryachev; D. D. Kaplunenko; V. B. Lobanov; S. V. Prants; A. F. Sergeev; N. V. Shlyk; M. Yu. Uleysky
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We present the results of in-situ measurements of $^{134}$Cs and $^{137}$Cs released from the Fukushima Nuclear Power Plant (FNPP) collected at surface and different depths in the western North Pacific in June and July 2012. It was found that 15 month after the incident concentrations of radiocesium in the Japan and Okhotsk seas were at background or slightly increased level, while they had increased values in the subarctic front area east of Japan. The highest concentrations of $^{134}$Cs and...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1410.2359
0
0.0
Jun 27, 2018
06/18
by
Cesar B. Rocha; William R. Young; Ian Grooms
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We study the representation of solutions of the three-dimensional quasigeostrophic (QG) equations using Galerkin series with standard vertical modes, with particular attention to the incorporation of active surface buoyancy dynamics. We extend two existing Galerkin approaches (A and B) and develop a new Galerkin approximation (C). Approximation A, due to \cite{flierl1978}, represents the streamfunction as a truncated Galerkin series and defines the potential vorticity (PV) that satisfies the...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1504.03361
0
0.0
Jun 27, 2018
06/18
by
Michael Wilkinson
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Rainfall from ice-free cumulus clouds requires collisions of large numbers of microscopic droplets to create every raindrop. The onset of rain showers can be surprisingly rapid, much faster than the mean time required for a single collision. Large-deviation theory is used to explain this observation.
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1506.02807
1
1.0
Jun 29, 2018
06/18
by
A. L. Virovlyansky
texts
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A method is proposed for finding the wave field components which are weakly sensitive to the sound speed perturbation in the ocean acoustic waveguides. Such a component is formed by a narrow beam of rays whose spread in vertical direction, up to the observation range, remains less than the vertical scale of perturbation. These rays pass through practically the same inhomogeneities and therefore their phases acquire close increments. If the ray amplitudes vary insignificantly, then (i) the...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1610.02568
0
0.0
Jun 30, 2018
06/18
by
S. V. Prants; V. I. Ponomarev; M. V. Budyansky; M. Yu. Uleysky; P. A. Fyman
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The output from an eddy-resolved multi-layered circulation model is used to analyze the vertical structure of simulated deep-sea eddies in the Japan Basin of the Japan/East Sea constrained by bottom topography. We focus on Lagrangian analysis of anticyclonic eddies, generated in the model in a typical year approximately at the place of the mooring and the hydrographic sections, where such eddies have been regularly observed in different years (1993--1997, 1999--2001). Using a quasi-3D...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1410.2344
0
0.0
Jun 30, 2018
06/18
by
E. A. Kherani; B. R. Tiwari; J. H. A. Sobral
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In this work, we study the growth characteristics of the convective instability (CI) in the dry troposphere by relaxing the adiabatic compressibility condition of Oberbeck-Boussinesq (OB) approach. We derive a new non-adiabatic-Boussinesq (NAB) expression for the modified Brunt-Vaisala frequency $(\omega_b)$, without considering the adiabatic compressibility condition of OB approach. This NAB expression reduces to the known Oberbeck-Boussinesq (OB) expression under adiabatic compressibility...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1408.6208
2
2.0
Jun 29, 2018
06/18
by
Srikanth Toppaladoddi; John S. Wettlaufer
texts
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We study the seasonal changes in the thickness distribution of Arctic sea ice, $g(h)$, under climate forcing. Our analytical and numerical approach is based on a Fokker-Planck equation for $g(h)$ (Toppaladoddi \& Wettlaufer \emph{Phys. Rev. Lett.} {\bf 115}, 148501, 2015), in which the thermodynamic growth rates are determined using observed climatology. In particular, the Fokker-Planck equation is coupled to the observationally consistent thermodynamic model of Eisenman \& Wettlaufer...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1611.01045
3
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
texts
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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
2
2.0
Jun 29, 2018
06/18
by
Michael P. Byrne; Paul A. O'Gorman
texts
eye 2
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Climate models simulate a strong land-ocean contrast in the response of near-surface relative humidity to global warming: relative humidity tends to increase slightly over oceans but decrease substantially over land. Surface energy balance arguments have been used to understand the response over ocean but are difficult to apply over more complex land surfaces. Here, a conceptual box model is introduced, involving moisture transport between the land and ocean boundary layers and...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1605.00380
0
0.0
Jun 28, 2018
06/18
by
F. Spineanu; M. Vlad
texts
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This work is intended to be a contribution to the study of the morphology of the rising convective columns, for a better representation of the processes of entrainment and detrainment. We examine technical methods for the description of the interface of expanding clouds and reveal the role of \emph{fingering} instability which increases the effective length of the periphery of the cloud. Assuming Laplacian growth we give a detailed derivation of the time-dependent conformal transformation that...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1508.04240
1
1.0
Jun 26, 2018
06/18
by
Aviad Levis; Yoav Y. Schechner; Amit Aides; Anthony B. Davis
texts
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This paper introduces a method to preform optical tomography, using 3D radiative transfer as the forward model. We use an iterative approach predicated on the Spherical Harmonics Discrete Ordinates Method (SHDOM) to solve the optimization problem in a scalable manner. We illustrate with an application in remote sensing of a cloudy atmosphere.
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1501.06093
0
0.0
Jun 28, 2018
06/18
by
Chirag Dhara; Maik Renner; Axel Kleidon
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Convective and radiative cooling are the two principle mechanisms by which the Earth's surface transfers heat into the atmosphere and that shape surface temperature. However, this partitioning is not sufficiently constrained by energy and mass balances alone. We use a simple energy balance model in which convective fluxes and surface temperatures are determined with the additional thermodynamic limit of maximum convective power. We then show that the broad geographic variation of heat fluxes...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1512.01374
0
0.0
Jun 30, 2018
06/18
by
Markus Gross
texts
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Seven data sources are analyzed and combined to form a surface wind speed climatology for the Gulf of California.
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1704.05922
0
0.0
Jun 30, 2018
06/18
by
Jaroslaw Piwonski; Thomas Slawig
texts
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The simulation and parameter optimization of coupled ocean circulation and ecosystem models in three space dimensions is one of the most challenging tasks in numerical climate research. Here we present a scientific toolkit that aims at supporting researchers by defining clear coupling interfaces, providing state-of-the-art numerical methods for simulation, parallelization and optimization while using only freely available and (to a great extend) platform-independent software. Besides defining a...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1410.0204
0
0.0
Jun 30, 2018
06/18
by
Nobuaki Shimoji; Ryoma Aoyama
texts
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In present work, we propose the analysis method of lightning based on the color analysis. We analyzed the digital still images in which the cloud-to-ground (CG) and intracloud (IC) lightning flashes are shown. Applying some digital image processing techniques, we extracted lightning channels. Then, the correlated color temperature (CCT) of the extracted lightning channels was obtained by mapping digital pixels of the extracted lightning channels to CIE 1931 xy-chromaticity diagram. Our results...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1412.8031
0
0.0
Jun 29, 2018
06/18
by
Inderpreet Kaur; Andrea Mentrelli; Frédéric Bosseur; Jean-Baptiste Filippi; Gianni Pagnini
texts
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This paper presents a mathematical approach to model the effects of phenomena with random nature such as turbulence and fire-spotting into the existing wildfire simulators. The formulation proposes that the propagation of the fire-front is the sum of a drifting component (obtained from an existing wildfire simulator without turbulence and fire-spotting) and a random fluctuating component. The modelling of the random effects is embodied in a probability density function accounting for the...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1601.06272
1
1.0
Jun 27, 2018
06/18
by
Sally Dacie
texts
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Some initial investigations into various atmospheric phenomena and the influence of the solar cycle on weather have been made. Strongly negative North Atlantic Oscillation (NAO) indices, which cause cold and dry winter weather in North West Europe, rarely occur during periods of high solar activity. Coupling between the troposphere and stratosphere is discussed, particularly in the context of Polar-night jet oscillation events (defined by Hitchcock et al., 2013) and the Quasi-Biennial...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1505.05285
1
1.0
Jun 29, 2018
06/18
by
Kelsey L. Ruckert; Gary Shaffer; David Pollard; Yawen Guan; Tony E. Wong; Chris E. Forest; Klaus Keller
texts
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The response of the Antarctic ice sheet (AIS) to changing climate forcings is an important driver of sea-level changes. Anthropogenic climate change may drive a sizeable AIS tipping point response with subsequent increases in coastal flooding risks. Many studies analyzing flood risks use simple models to project the future responses of AIS and its sea-level contributions. These analyses have provided important new insights, but they are often silent on the effects of potentially important...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1609.06338
0
0.0
Jun 29, 2018
06/18
by
Takahito Mitsui; Michel Crucifix
texts
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It is well acknowledged that the sequence of glacial-interglacial cycles is paced by the astronomical forcing. However, how much is the sequence robust against natural fluctuations associated, for example, with the chaotic motions of atmosphere and oceans? In this article, the stability of the glacial-interglacial cycles is investigated on the basis of simple conceptual models. Specifically, we study the influence of additive white Gaussian noise on the sequence of the glacial cycles generated...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1611.03295
1
1.0
Jun 28, 2018
06/18
by
Zhiyu Liu
texts
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The stability of stratified flows at locations in the Clyde, Irish and Celtic Seas on the UK Continental Shelf is examined. Flows are averaged over periods of 12-30 min in each hour, corresponding to the times taken to obtain reliable estimates of the rate of dissipation of turbulent kinetic energy per unit mass, $\varepsilon$. The Taylor-Goldstein equation is solved to find the maximum growth rate of small disturbances to these averaged flows, and the critical gradient Richardson number,...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1512.07055
0
0.0
Jun 29, 2018
06/18
by
Erica Rosenblum; Ian Eisenman
texts
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The downward trend in Arctic sea ice extent is one of the most dramatic signals of climate change during recent decades. Comprehensive climate models have struggled to reproduce this, typically simulating a slower rate of sea ice retreat than has been observed. However, this bias has been widely noted to have decreased in models participating in the most recent phase of the Coupled Model Intercomparison Project (CMIP5) compared with the previous generation of models (CMIP3). Here we examine...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1605.07698
0
0.0
Jun 28, 2018
06/18
by
Jan P. Viebahn; Anna S. von der Heydt; Dewi Le Bars; Henk A. Dijkstra
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The climate impact of ocean gateway openings during the Eocene-Oligocene transition is still under debate. Previous model studies employed grid resolutions at which the impact of mesoscale eddies has to be parameterized. We present results of a state-of-the-art eddy-resolving global ocean model with a closed Drake Passage, and compare with results of the same model at non-eddying resolution. An analysis of the pathways of heat by decomposing the meridional heat transport into eddy, horizontal,...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1510.04141
0
0.0
Jun 28, 2018
06/18
by
G. M. Webb; C. T. Duba; Q. Hu
texts
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Green's functions for Rossby waves in an azimuthal wind are obtained, in which the stream-function $\psi$ depends on $r$, $\phi$ and $t$, where $r$ is cylindrical radius and $\phi$ is the azimuthal angle in the $\beta$-plane relative to the easterly direction, in which the $x$-axis points east and the $y$-axis points north. The Rossby wave Green's function with no wind is obtained using Fourier transform methods, and is related to the previously known Green's function obtained for this case,...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1510.00875
0
0.0
Jun 30, 2018
06/18
by
Hege-Beate Fredriksen; Martin Rypdal
texts
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The temporal fluctuations in global mean surface temperature is an example of a geophysical quantity which can be described using the notions of long-range persistence and scale invariance/scaling, but this description has suffered from lack of a generally accepted physical explanation. Processes with these statistical signatures can arise from non-linear effects, for instance through cascade-like energy transfer in turbulent fluids, but they can also be produced by linear models with...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1701.07355
0
0.0
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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0.0
Jun 29, 2018
06/18
by
James B. Elsner; Thomas H. Jagger; Tyler Fricker
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This paper estimates local tornado risk from records of past events using statistical models. First, a spatial model is fit to the tornado counts aggregated in counties with terms that control for changes in observational practices over time. Results provide a long-term view of risk that delineates the main tornado corridors in the United States where the expected annual rate exceeds two tornadoes per 10,000 square km. A few counties in the Texas Panhandle and central Kansas have annual rates...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1606.07325
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2.0
Jun 27, 2018
06/18
by
Samrat Rao
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An atmospheric general circulation model (AGCM) with idealized and complete physics has been used to evaluate the Tropical Easterly Jet (TEJ) jet. In idealized physics, the role of upper tropospheric friction has been found to be important in getting realistic upper tropospheric zonal wind patterns in response to heating. In idealized physics, the location and strength of the TEJ as a response to Gill heating has been studied. Though the Gill model is considered to be widely successful in...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1505.04903
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0.0
Jun 30, 2018
06/18
by
Anna S. von der Heydt; Peter Köhler; Roderik S. W. van de Wal; Henk A. Dijkstra
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Palaeo data have been frequently used to determine the equilibrium (Charney) climate sensitivity $S^a$, and - if slow feedback processes (e.g. land ice-albedo) are adequately taken into account - they indicate a similar range as estimates based on instrumental data and climate model results. Most studies implicitly assume the (fast) feedback processes to be independent of the background climate state, e.g., equally strong during warm and cold periods. Here we assess the dependency of the fast...
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1403.5391
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Jun 29, 2018
06/18
by
Niklas Brännström; Leif Å Persson
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We consider a bilevel optimatisation method for inverse linear atmospheric dispersion problems where both linear and non-linear model parameters are to be determined. We propose that a smooth weighted Mahalanobis distance function is used and derive sufficient conditions for when the follower problem has local strict convexity. A few toy-models are presented where local strict convexity and ill-posedness of the inverse problem are explored, indeed the smooth distance function is compared and...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1607.04804
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0.0
Jun 29, 2018
06/18
by
Philip Sura
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Earth's atmosphere is in a state far from thermodynamic equilibrium. For example, the large scale equator-to-pole temperature gradient is maintained by tropical heating, polar cooling, and a midlatitude meridional eddy heat flux predominantly driven by baroclinically unstable weather systems. Based on basic thermodynamic principles, it can be shown that the meridional heat flux, in combination with the meridional temperature gradient, acts to maximize entropy production of the atmosphere. In...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1603.05260
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3.0
Jun 27, 2018
06/18
by
Philip E. Bett; Hazel E. Thornton
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We use reanalysis data to investigate the daily co-variability of wind and solar irradiance in Britain, and its implications for renewable energy supply balancing. The joint distribution of daily-mean wind speeds and irradiances shows that irradiance has a much stronger seasonal cycle than wind, due to the rotational tilt of the Earth. Irradiance is weakly anticorrelated with wind speed throughout the year ($-0.4 \lesssim \rho \lesssim -0.2$): there is a weak tendency for windy days to be...
Topics: Atmospheric and Oceanic Physics, Physics
Source: http://arxiv.org/abs/1505.07071
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Jun 30, 2018
06/18
by
F. Drullion; S. G. Sajjadi
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In this paper we demonstrate numerical computations of turbulent wind blowing over group of waves that are growing in time. The numerical model adopted for the turbulence model is based on differential second-moment model that was adopted for growing idealized waves by Drullion and Sajjadi (2014). The results obtained here demonstrate the formation of cat's-eye which appear asymmetrically over the waves within a group.
Topics: Physics, Atmospheric and Oceanic Physics
Source: http://arxiv.org/abs/1704.05052
