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Unlikely existence of $k_x^{-1}$ spectral law in wall turbulence: an observation of the atmospheric surface layerFeb 20 2019For wall turbulence, there has been predicted a range of streamwise wavenumbers $k_x$ such that the spectral density of streamwise velocity fluctuations is proportional to $k_x^{-1}$. The existence or nonexistence of this $k_x^{-1}$ law is examined here. ... More
Cascading failures in scale-free interdependent networksFeb 19 2019Large cascades are a common occurrence in many natural and engineered complex systems. In this paper we explore the propagation of cascades across networks using realistic network topologies, such as heterogeneous degree distributions, as well as intra- ... More
Open-ocean interior moored sensor turbulence estimates, below a MeddyFeb 18 2019A one-year time series of moored high-resolution temperature T-sensor data from 1455 m depth on a 3900 m long line in about 5300 m of water in the NE-Atlantic Canary Basin are dominated by salinity (over-)compensated intrusions arising from the effects ... More
Super-Resolution Simulation for Real-Time Prediction of Urban MicrometeorologyFeb 14 2019We propose a super-resolution (SR) simulation system that consists of a physics-based meteorological simulation and an SR method based on a deep convolutional neural network (CNN). The CNN is trained using pairs of high-resolution (HR) and low-resolution ... More
A Consistent Reduced Network for HCN Chemistry in Early Earth and Titan Atmospheres: Quantum Calculations of Reaction Rate CoefficientsFeb 14 2019HCN is a key ingredient for synthesizing biomolecules such as nucleobases and amino acids. We calculate 42 reaction rate coefficients directly involved with or in competition with the production of HCN in the early Earth or Titan atmospheres. These reactions ... More
Understanding the dynamics of biological and neural oscillator networks through mean-field reductions: a reviewFeb 14 2019Many biological and neural system can be seen as networks of interacting periodic processes. Importantly, the function of these networks depends on the collective dynamics: Synchrony of oscillations is probably amongst the most prominent examples of collective ... More
Wave attenuation and dispersion due to floating ice coversFeb 14 2019Experiments investigating the attenuation and dispersion of surface waves in a variety of ice covers are performed using a refrigerated wave flume. The ice conditions tested in the experiments cover naturally occurring combinations of continuous, fragmented, ... More
Observing Microscopic Transitions from Macroscopic Bursts: Instability-Mediated Resetting in the Incoherent Regime of the $D$-dimensional Generalized Kuramoto ModelFeb 13 2019We consider a recently introduced $D$-dimensional generalized Kuramoto model for many $(N\gg 1)$ interacting agents in which the agent states are $D$-dimensional unit vectors. It was previously shown that, for even $D$, similar to the original Kuramoto ... More
A method for generating coherent spatially explicit maps of seasonal palaeoclimates from site-based reconstructionsFeb 13 2019We describe a new method for reconstructing spatially explicit maps of seasonal palaeoclimate variables from site based reconstructions. Using a 3D-Variational technique, the method finds the best linear unbiased estimate of the palaeoclimate given the ... More
Numerical analysis of the multi-fluid equations with applications for convection modellingFeb 13 2019Convection schemes are a large source of error in global weather and climate models, and modern resolutions are often too fine to parameterize convection but are still too coarse to fully resolve it. Recently, numerical solutions of multi-fluid equations ... More
A theoretical model for realistic local climatesFeb 13 2019We address the question of writing a model that ---considering the doubly-periodic forcing induced by solar radiation and the laws of irradiance and conduction--- reproduces realistic annual and daily modulations of temperatures on the surface of a small ... More
A new diagnostic tool for water, energy and entropy budgets in climate modelsFeb 12 2019This work presents a novel diagnostic tool for studying the thermodynamics of the climate systems with a wide range of applications, from sensitivity studies to model tuning. It includes a number of modules for assessing the internal energy budget, the ... More
Deep Learning for Scientific Inference from Geophysical Data: The Madden-Julian Oscillation as a Test CaseFeb 12 2019Deep learning can recognize complex geophysical phenomena by inferring which variables are important for their identification and understanding their spatial characteristics. We use a particular mode of multi-scale tropical atmospheric variability, the ... More
The emission of energetic electrons from the complex streamer corona adjacent to leader steppingFeb 12 2019We here propose a model to capture the complexity of the streamer corona adjacent to leader stepping and relate it to the production of energetic electrons serving as a source of X-rays and $\gamma$-rays, manifesting in terrestrial gamma-ray flashes (TGFs). ... More
Surface waves enhance particle dispersionFeb 11 2019We study the horizontal dispersion of passive tracer particles on the free surface of gravity waves in deep water. For random linear waves with the JONSWAP spectrum, the Lagrangian particle trajectories are computed using an exact nonlinear model known ... More
Precipitable Water Vapor, Temperature, and Wind Statistics At Sites Suitable for mm and Submm Wavelength Astronomy in Northern ChileFeb 11 2019Atmospheric water vapor is the main limiting factor of atmospheric transparency in the mm and submm wavelength spectral windows. Thus, dry sites are needed for the installation and successful operation of radio astronomy observatories exploiting those ... More
Diffusion of inertia-gravity waves by geostrophic turbulenceFeb 11 2019The scattering of inertia-gravity waves by large-scale geostrophic turbulence in a rapidly rotating, strongly stratified fluid leads to the diffusion of wave energy on the constant-frequency cone in wavenumber space. We derive the corresponding diffusion ... More
Classifying attention deficit hyperactivity disorder in children with non-linearities in actigraphyFeb 10 2019Objective This study provides an objective measure based on actigraphy for Attention Deficit Hyperactivity Disorder (ADHD) diagnosis in children. We search for motor activity features that could allow further investigation into their association with ... More
Statistical Lyapunov theory based on bifurcation analysis of energy cascade in isotropic homogeneous turbulence: a physical--mathematical reviewFeb 09 2019This work presents a review of the previous articles dealing with an original turbulence theory proposed by the author, and provides new theoretical insights into some related issues. The new theoretical procedures and methodological approaches confirm ... More
The Influence of Time Series Distance Functions on Climate NetworksFeb 08 2019Network theory has established itself as an important tool for the analysis of complex systems such as the climate. In this context, climate networks are constructed using a spatiotemporal climate dataset and a time series distance function. It consists ... More
Derivation of Delay Equation Climate Models Using the Mori-Zwanzig FormalismFeb 08 2019Models incorporating delay have been frequently used to understand climate variability phenomena, but often the delay is introduced through an ad-hoc physical reasoning, such as the propagation time of waves. In this paper, the Mori-Zwanzig formalism ... More
Quantitative analysis of self-organized patterns in ombrotrophic peatlandsFeb 07 2019We numerically investigate a diffusion-reaction model of an ombrotrophic peatland implementing a Turing instability relying on nutrient accumulation. We propose a systematic and quantitative sorting of the vegetation patterns, based on the statistical ... More
Portable device to determine particle asymmetry parameterFeb 06 2019Accurate characterization of the asymmetry parameter g is of crucial importance for many radiative transfer and climate models. Here, we present our portable light scattering (PLS) device which is designed for in situ, real-time, and contact-free measurements ... More
Uncovering temporal regularity in atmospheric dynamics through Hilbert phase analysisFeb 06 2019Uncovering meaningful regularities in complex oscillatory signals is a challenging problem with applications across a wide range of disciplines. Here we present a novel approach, based on the Hilbert transform (HT). We show that temporal periodicity can ... More
Long Term Trends in Atmospheric Pressure and its VarianceFeb 04 2019We use the Global Historical Climatology Network--daily database to calculate trends in sea-level atmospheric pressures, their variance and the variance of their day-to-day differences in nine regions of the world. Changes in pressure reflect the addition ... More
Topological Convergence of Urban Infrastructure NetworksFeb 04 2019Urban infrastructure networks play a major role in providing reliable flows of multitude critical services demanded by citizens in modern cities. We analyzed here a database of 125 infrastructure networks, roads (RN); urban drainage networks (UDN); water ... More
Magnetic eddy viscosity of mean sheared flows in two-dimensional magnetohydrodynamicsFeb 04 2019Induction of magnetohydrodynamics (MHD) fluids at magnetic Reynolds number (Rm) less than~1 has long been known to cause magnetic drag. Here, we show that when $\Rm \gg 1$, and additionally in a hydrodynamic-dominated regime in which the magnetic energy ... More
New combinational therapies for cancer using modern statistical mechanicsFeb 02 2019We investigate a new dynamical system that describes tumor-host interaction. The equation that describes the untreated tumor growth is based on non-extensive statistical mechanics. Recently, this model has been shown to fit successfully exponential, Gompertz, ... More
Spatial inhomogeneities in the sedimentation of biogenic particles in ocean flows: analysis in the Benguela regionFeb 01 2019Sedimentation of particles in the ocean leads to inhomogeneous horizontal distributions at depth, even if the release process is homogeneous. We study this phenomenon considering a horizontal sheet of falling particles immersed in an oceanic flow, and ... More
The Effects of Gravity on the Climate and Circulation of a Terrestrial PlanetJan 31 2019The climate and circulation of a terrestrial planet are governed by, among other things, the distance to its host star, its size, rotation rate, obliquity, atmospheric composition and gravity. Here we explore the effects of the last of these, the Newtonian ... More
Impact of large scale climate oscillation on drought in West AfricaJan 29 2019Drought poses a significant threat to the delicate economies in subsaharan Africa. This study investigates the influence of large scale ocean oscillation on drought in West Africa. Standardized Precipitation Index for the region was computed using monthly ... More
Basin bifurcations, oscillatory instability and rate-induced thresholds for AMOC in a global oceanic box modelJan 29 2019The Atlantic Meridional Overturning Circulation (AMOC) transports substantial amounts of heat into the North Atlantic sector, and hence is of very high importance in regional climate projections. The AMOC has been observed to show multi-stability across ... More
A network model of immigration: Enclave formation vs. cultural integrationJan 27 2019Successfully integrating newcomers into native communities has become a key issue for policy makers, as the growing number of migrants has brought cultural diversity, new skills, and at times, societal tensions to receiving countries. We develop an agent-based ... More
Flocking and spreading dynamics in populations of self-propelled agentsJan 25 2019Populations of self-propelled mobile agents - animal groups, robot swarms or crowds of people - that exchange information with their surrounding, host fascinating cooperative behaviors. While in many situations of interest the agents motion is driven ... More
Modeling the chemical impact and the optical emissions produced by lightning-induced electromagnetic fields in the upper atmosphere: the case of halos and elves triggered by different lightning dischargesJan 22 2019Halos and elves are Transient Luminous Events (TLEs) produced in the lower ionosphere as a consequence of lightning-driven electromagnetic fields. These events can influence the upper-atmospheric chemistry and produce optical emissions. We have developed ... More
Stability of the Malvinas CurrentJan 21 2019Deterministic and probabilistic tools from nonlinear dynamics are used to assess enduring near-surface Lagrangian aspects of the Malvinas Current. The deterministic tools are applied on a multi-year record of velocities derived from satellite altimetry ... More
A subspace pursuit method to infer refractivity in the marine atmospheric boundary layerJan 18 2019Inferring electromagnetic propagation characteristics within the marine atmospheric boundary layer (MABL) from data in real time is crucial for modern maritime navigation and communications. The propagation of electromagnetic waves is well modeled by ... More
A New Weighting Scheme in Weighted Markov Model for Predicting the Probability of Drought EpisodesJan 18 2019Drought is a complex stochastic natural hazard caused by prolonged shortage of rainfall. Several environmental factors are involved in determining drought classes at the specific monitoring station. Therefore, efficient sequence processing techniques ... More
The Impact of Hurricanes on the Oceanographic Conditions in the Exclusive Economic Zone of CubaJan 17 2019In this work, we analysed the satellite-based responses of sea surface temperature (SST) and chlorophyll-a (chl-a) concentration in the waters of the Exclusive Economic Zone (EEZ) of Cuba to hurricanes that crossed the EEZ between 1998 and 2016. We considered ... More
Laboratory investigations of the bending rheology of floating saline ice, and physical mechanisms of wave damping, in the HSVA ice tankJan 16 2019An experiment on the propagation of flexural-gravity waves was performed in the HSVA ice tank. Physical characteristics of the water-ice system were measured in different locations in the tank during the tests, with a number of sensors deployed in the ... More
Effects of hidden nodes on the reconstruction of bidirectional networksJan 14 2019Much research effort has been devoted to developing methods for reconstructing the links of a network from dynamics of its nodes. Many current methods require the measurements of the dynamics of all the nodes be known. In real-world problems, it is common ... More
Exact universal excitation waveform for optimal enhancement of directed ratchet transportJan 10 2019The existence and properties of an exact universal excitation waveform for optimal enhancement of directed ratchet transport are deduced from the criticality scenario giving rise to ratchet universality, and confirmed by numerical experiments in the context ... More
Simulating Non-hydrostatic atmospheres on Planets (SNAP): formulation, validation and application to the Jovian atmosphereJan 09 2019A new non-hydrostatic and cloud-resolving atmospheric model is developed for studying moist convection and cloud formation in planetary atmospheres. It is built on top of the Athena++ framework, utilizing its static/adaptive mesh-refinement, parallelization, ... More
Wave kinetic equation for inhomogeneous drift-wave turbulence beyond the quasilinear approximationJan 08 2019The formation of zonal flows from inhomogeneous drift-wave (DW) turbulence is often described using statistical theories derived within the quasilinear approximation. However, this approximation neglects wave--wave collisions. Hence, some important effects ... More
An Open Source, Versatile, Affordable Waves in Ice Instrument for Remote Sensing in the Polar RegionsJan 08 2019Sea ice is a major feature of the polar environments. Recent changes in the climate and extent of the sea ice, together with increased economic activity and research interest in these regions, are driving factors for new measurements of sea ice dynamics. ... More
Errors induced by the neglect of polarization in radiance calculations for three-dimensional cloudy atmospheresJan 07 2019Remote sensing instruments observe radiation being scattered and absorbed by molecules, aerosol particles, cloud droplets and ice crystals. In order to interpret and accurately model such observations, the vector radiative transfer equation needs to be ... More
IPRT polarized radiative transfer model intercomparison project - Three-dimensional test cases (phase B)Jan 07 2019Initially unpolarized solar radiation becomes polarized by scattering in the Earth's atmosphere. In particular molecular scattering polarizes electromagnetic radiation, but also scattering of radiation at aerosols, cloud droplets and ice crystals polarizes. ... More
IPRT polarized radiative transfer model intercomparison project - Phase AJan 07 2019The polarization state of electromagnetic radiation scattered by atmospheric particles such as aerosols, cloud droplets, or ice crystals contains much more information about the optical and microphysical properties than the total intensity alone. For ... More
The Middle Pleistocene Transition by frequency locking and slow ramping of internal periodJan 06 2019The increase in glacial cycle length from approximately $41$ to on average $100$ thousand years around $1$ million years ago, called the Middle Pleistocene Transition (MPT), lacks a conclusive explanation. We describe a dynamical mechanism which we call ... More
Fourier analysis of a delayed Rulkov neuron networkJan 04 2019We have analyzed the synchronization of a small-world network of chaotic Rulkov neurons with an electrical coupling that contains a delay. We have developed an algorithm to compute a certain delay whose result is to improve the synchronization of the ... More
Effect of the land surface thermal patchiness on the Atmospheric Boundary Layer through a quantification of the dispersive fluxesJan 02 2019While advances in computation are enabling finer grid resolutions in numerical weather prediction models, representing land-atmosphere exchange processes as a lower boundary condition remains a challenge. This partially results of the fact that land-surface ... More
Chaotic signature of climate extremesDec 28 2018Understanding the dynamics of climate extreme is important in its prediction and modeling. In this study, linear trends in percentile, threshold, absolute, and duration based temperature and precipitation extremes indicator were obtained for the period ... More
A biologically motivated three-species exclusion model: effects of leaky scanning and overlapping genes on initiation of protein synthesisDec 25 2018Totally asymmetric simple exclusion process (TASEP) was originally introduced as a model for the traffic-like collective movement of ribosomes on a messenger RNA (mRNA) that serves as the track for the motor-like forward stepping of individual ribosomes. ... More
Internal gravity waves in the energy and flux budget turbulence-closure theory for shear-free stably stratified flowsDec 25 2018We have advanced the energy and flux budget (EFB) turbulence closure theory that takes into account a two-way coupling between internal gravity waves (IGW) and the shear-free stably stratified turbulence. This theory is based on the budget equation for ... More
Hydrodynamic models of preference formation in multi-agent societiesDec 24 2018In this paper, we discuss the passage to hydrodynamic equations for kinetic models of opinion formation. The considered kinetic models feature an opinion density depending on an additional microscopic variable, identified with the personal preference. ... More
Analysis of contagion maps on a class of networks that are spatially embedded in a torusDec 24 2018A spreading process on a network is influenced by the network's underlying spatial structure, and it is insightful to study the extent to which a spreading process follows such structure. We consider a threshold contagion on a network whose nodes are ... More
Is Carbon Cycling Keeping Pace with Increases in Atmospheric Carbon Dioxide?Dec 20 2018Carbon dioxide (CO2) increase has been well documented, and global net primary production is of importance to a variety of ecological topics. Since CO2 increases primary production in laboratory experiments, the global effects of increasing CO2 on global ... More
Spatially Tracking Wave Events in Partitioned Numerical Wave Model OutputsDec 17 2018Numerical wave models can output partitioned wave parameters at each grid point using a spectral partitioning technique. Because these wave partitions are usually organized according to the magnitude of their wave energy without considering the coherence ... More
Assessing the predictability of Medicanes in ECMWF ensemble forecasts using an object-based approachDec 16 2018The predictability of eight southern European tropical-like cyclones, seven of which Medicanes, is studied evaluating ECMWF operational ensemble forecasts against operational analysis data. Forecast cyclone trajectories are compared to the cyclone trajectory ... More
The dynamics of two-stage contagionDec 15 2018Dec 29 2018We explore simple models aimed at the study of social contagion, in which contagion proceeds through two stages. When coupled with demographic turnover, we show that two-stage contagion leads to nonlinear phenomena which are not present in the basic `classical' ... More
Individual decision making in task-oriented groupsDec 14 2018The strategies adopted by individuals to select relevant information to pass on are central to understanding problem solving by groups. Here we use agent-based simulations to revisit a cooperative problem-solving scenario where the task is to find the ... More
The FLUXCOM ensemble of global land-atmosphere energy fluxesDec 11 2018Although a key driver of Earth's climate system, global land-atmosphere energy fluxes are poorly constrained. Here we use machine learning to merge energy flux measurements from FLUXNET eddy covariance towers with remote sensing and meteorological data ... More
Development of bed forms due to waves blocked by a counter currentDec 11 2018Experiments are conducted in a laboratory flume on the propagation of a surface wave against unidirectional flow with a sediment bed. This paper presents the spatial variation of bed forms induced by the wave-blocking phenomenon by a suitably tuned uniform ... More
Circadian rhythm of dune-field activityDec 10 2018Wind-blown sand dunes are ubiquitous in the solar system, and their emergence and subsequent form have been related to regional climate dynamics$^{1-4}$. Dune fields are reservoirs for airborne dust$^{5}$, which modulates global climate$^{6}$ and impacts ... More
Complementarity Assessment of South Greenland Katabatic Flows and West Europe Wind RegimesDec 05 2018Current global environmental challenges require firm, yet diverse resolutions in the energy sector. One promising solution consists in harnessing high-quality variable renewable energy (VRE) resources in remote locations, while using transmission links ... More
Tropical transition of Hurricane Chris (2012) over the North Atlantic Ocean: A multi-scale investigation of predictabilityNov 29 2018Tropical cyclones that evolve from a non-tropical origin may pose a special challenge for predictions, as they often emerge at the end of a multi-scale cascade of atmospheric processes. Climatological studies have shown that the 'tropical transition' ... More
Tropospheric delay in microwave propagation in NigeriaNov 29 2018Satellite communication systems suffer from the systematic error of tropospheric delay. Accurate estimation of this delay is essential for communication budget and planning. This study investigates the tropospheric delay in three Nigeria cities: Abuja, ... More
A model for warm clouds with implicit droplet activation, avoiding saturation adjustmentNov 28 2018The representation of cloud processes in weather and climate models is crucial for their feedback on atmospheric flows. Since there is no general macroscopic theory of clouds, the parameterization of clouds in corresponding simulation software depends ... More
Intercomparison of Warm-Rain Bulk Microphysics Schemes using AsymptoticsNov 28 2018Clouds are important components of the atmosphere. Since it is usually not possible to treat them as ensembles of huge numbers of particles, parameterizations on the basis of averaged quantities (mass and/or number concentration) must be derived. Since ... More
Reducing the irreducible uncertainty in return periods of 21st-century precipitation extremesNov 26 2018Internal climate variability, captured through multiple initial condition ensembles, may be comparable to the variability caused by knowledge gaps in future emissions trajectories and in the physical science basis, especially at adaptation-relevant scales ... More
Lagrangian study of the final warming in the southern stratosphere during 2002: Part II. 3D structureNov 25 2018This two-part paper aims to provide a Lagrangian perspective of the final southern warming in spring of 2002, during which the stratospheric polar vortex (SPV) experienced a unique splitting. We approach the subject from a dynamical systems viewpoint ... More
Lagrangian study of the final warming in the southern stratosphere during 2002: Part I. The Vortex Splitting at Upper LevelsNov 24 2018The present two-part paper provides a Lagrangian perspective of the final southern warming in 2002, during which the stratospheric polar vortex (SPV) experienced a unique splitting. Part I focuses on the understanding of fundamental processes for filamentation ... More
Modeling of raining season onset and cessation of tropical rainfall for climate change adaptation in AgricultureNov 21 2018This study investigates the trend in Rainfall Onset Dates (ROD), Rainfall Cessation Dates (RCD), Length of Growing Seasons (LGS) and Rainfall Amount at Onset of Rainfall (RAO) using linear regression, Mann-Kendall, Sen Slope and Hurst Exponent for four ... More
Supercooled fog as a natural laboratory for studying ice formation in cloudsNov 10 2018The ice phase in clouds contributes largely to uncertainties in global climate models partly due to a lack of atmospheric observations. At moderate supercooling ice nucleating particles (INP) and ice particles (IP) are present in small concentrations ... More
Adaptive Diffusion Processes of Time-Varying Local Information on NetworksNov 10 2018This paper mainly discusses the diffusion on complex networks with time-varying couplings. We propose a model to describe the adaptive diffusion process of local topological and dynamical information, and find that the Barabasi-Albert scale-free network ... More
Anomaly Detection in Paleoclimate Records using Permutation EntropyNov 03 2018Nov 29 2018Permutation entropy techniques can be useful in identifying anomalies in paleoclimate data records, including noise, outliers, and post-processing issues. We demonstrate this using weighted and unweighted permutation entropy of water-isotope records in ... More
Global climate modeling of Saturn's atmosphere. Part II: multi-annual high-resolution dynamical simulationsNov 03 2018The Cassini mission unveiled the intense and diverse activity in Saturn's atmosphere: banded jets, waves, vortices, equatorial oscillations. To set the path towards a better understanding of those phenomena, we performed high-resolution multi-annual numerical ... More
Regime Transition in the Energy Cascade of Rotating TurbulenceNov 02 2018Transition from a split to a forward kinetic energy cascade system is explored in the context of rotating turbulence using direct numerical simulations with a three-dimensional isotropic random force uncorrelated with the velocity field. Our parametric ... More
Hadley cell emergence and extent in axisymmetric, nearly inviscid, planetary atmospheresOct 25 2018The authors consider constraints from axisymmetric, nearly inviscid theory on Hadley cell emergence and extent in dry planetary atmospheres. Existing versions of the well-known Hide's constraint relating Hadley cell emergence to the distributions of absolute ... More
Effects of the second virial coefficient on the tropospheric adiabatic lapse rateOct 24 2018We report the effect of considering as equation of state a virial expansion up to second order in the calculation of the adiabatic lapse rate. In the process, we have derived many thermodynamic functions necessary to our aim, like the internal energy, ... More
Evolution of 21st Century Sea-level Rise ProjectionsOct 18 2018The modern era of scientific global-mean sea-level rise (SLR) projections began in the early 1980s. In subsequent decades, understanding of driving processes has improved, and new methodologies have been developed. Nonetheless, despite more than 70 studies, ... More
Wave to pulse generation. From oscillatory synapse to train of action potentialsOct 18 2018Neurons have the capability of transforming information from a digital signal at the dendrites of the presynaptic termi- nal to an analogous wave at the synaptic cleft and back to a digital pulse when they achieve the required voltage for the generation ... More
A first measurement of the Planetary Boundary Layer top in Cali-Colombia: Elastic LiDAR applicationOct 16 2018The monitoring of the impact of aerosols in Latin America on a local scale is usually limited due to the infrastructure and instrumentation available. In Colombia, there are two international ground surface monitoring networks, the AErosol RObotic NETwork ... More
Wind Power Persistence is Governed by SuperstatisticOct 12 2018Oct 16 2018Mitigating climate change demands a transition towards renewable electricity generation, with wind power being a particularly promising technology. Long periods either of high or of low wind therefore essentially define the necessary amount of storage ... More
Nightside Winds at the Lower Clouds of Venus with Akatsuki/IR2: Longitudinal, local time and decadal variations from comparison with previous measurementsOct 12 2018Dec 10 2018We present measurements of the wind speeds at the nightside lower clouds of Venus from observations by JAXA's mission Akatsuki during 2016, complemented with new wind measurements from ground-based observations acquired with TNG/NICS in 2012 and IRTF/SpeX ... More
Arctic amplification metricsOct 09 2018One of the defining features of both recent and historical cases of global climate change is Arctic Amplification (AA). This is the more rapid change in the surface air temperature (SAT) in the Arctic compared to some wider reference region, such as the ... More
Analysis of extreme climate over NigeriaSep 30 2018The impact of extreme climate such as drought and flooding on agriculture, tourism, migration and peace in Nigeria is immense. There is the need to study the trend and statistics for better planning, preparation and adaptation. In this study, the statistical ... More
Forecasting water vapour above the sites of ESO's Very Large Telescope (VLT) and the Large Binocular Telescope (LBT)Sep 28 2018Water vapour in the atmosphere is the main source of the atmospheric opacity in the infrared and sub-millimetric regimes and its value plays a critical role in observations done with instruments working at these wavelengths on ground-based telescopes. ... More
Networks and the Resilience and Fall of Empires: a Macro-Comparison of the Imperium Romanum and Imperial ChinaSep 21 2018This paper proposes to proceed from a rather metaphorical application of network terminology on polities and imperial formations of the past to an actual use of tools and concepts of network science. For this purpose, a well established network model ... More
Spatial statistics of atmospheric particulate matter in ChinaSep 20 2018In this paper, the spatial dynamics of the atmospheric particulate matters (resp. PM$_{10}$ and PM$_{2.5}$) are studied using turbulence methodologies. It is found experimentally that the spatial correlation function $\rho(r)$ shows a log-law on the mesoscale ... More
Retrieval analysis of 38 WFC3 transmission spectra and resolution of the normalisation degeneracySep 18 2018A comprehensive analysis of 38 previously published Wide Field Camera 3 (WFC3) transmission spectra is performed using a hierarchy of nested-sampling retrievals: with versus without clouds, grey versus non-grey clouds, isothermal versus non-isothermal ... More
Measurements of tropospheric ice clouds with a ground-based CMB polarization experiment, POLARBEARSep 18 2018The polarization of the atmosphere has been a long-standing concern for ground-based experiments targeting cosmic microwave background (CMB) polarization. Ice crystals in upper tropospheric clouds scatter thermal radiation from the ground and produce ... More
Event Graphs: Advances and Applications of Second-Order Time-Unfolded Temporal Network ModelsSep 10 2018Recent advances in data collection and storage have allowed both researchers and industry alike to collect data in real time. Much of this data comes in the form of 'events', or timestamped interactions, such as email and social media posts, website clickstreams, ... More
Exact results for the extreme Thouless effect in a model of network dynamicsSep 02 2018If a system undergoing phase transitions exhibits some characteristics of both first and second order, it is said to be of 'mixed order' or to display the Thouless effect. Such a transition is present in a simple model of a dynamic social network, in ... More
Percolation Framework of the Earth's TopographySep 01 2018Feb 06 2019Self-similarity and long-range correlations are the remarkable features of the Earth's surface topography. Here we develop an approach based on percolation theory to study the geometrical features of Earth. Our analysis is based on high-resolution, 1 ... More
Constraining the Time Interval for the Origin of Life on EarthAug 28 2018Estimates of the time at which life arose on Earth make use of two types of evidence. First, astrophysical and geophysical studies provide a timescale for the formation of Earth and the Moon, for large impact events on early Earth, and for the cooling ... More
A new approach for rain gush formation associated with ionic windAug 24 2018Based upon experimental observation in the laboratory, we propose that ionic wind from corona discharge inside a thundercloud would play an important role in producing a rain gush. A cyclic chain of events inside a super-saturated environment in a thundercloud ... More
The impact of locally-enhanced vertical diffusivity on the cross-shelf transport of tracers induced by a submarine canyonAug 22 2018Feb 08 2019The exchanges of water, nutrients and oxygen between the coastal and open ocean are key components of on-shelf nutrient budgets and biogeochemical cycles. On a regional scale, submarine canyons enhance physical processes such as shelf-slope mass exchange ... More
A hierarchical statistical framework for emergent constraints: application to snow-albedo feedbackAug 17 2018Emergent constraints use relationships between future and current climate states to constrain projections of climate response. Here, we introduce a statistical, hierarchical emergent constraint (HEC) framework in order to link future and current climate ... More
Co-evolution of nodes and links: diversity driven coexistence in cyclic competition of three speciesAug 17 2018When three species compete cyclically in a well-mixed, stochastic system of $N$ individuals, extinction is known to typically occur at times scaling as the system size $N$. This happens, for example, in rock-paper-scissors games or conserved Lotka-Volterra ... More