A5025877841- Complex Systems and Time Series Analysis
- Solar and Space Plasma Dynamics
- Geomagnetism and Paleomagnetism Studies
- Ionosphere and magnetosphere dynamics
- Magnetic confinement fusion research
- Earthquake Detection and Analysis
- Climate variability and models
- Theoretical and Computational Physics
- Advanced Thermodynamics and Statistical Mechanics
- Advanced Data Storage Technologies
- Statistical Mechanics and Entropy
- Financial Risk and Volatility Modeling
- Ecosystem dynamics and resilience
- Meteorological Phenomena and Simulations
- Geophysics and Gravity Measurements
- Nuclear Physics and Applications
- Fractional Differential Equations Solutions
- Fusion materials and technologies
- Nuclear reactor physics and engineering
- Cloud Computing and Resource Management
- Global Energy and Sustainability Research
- Market Dynamics and Volatility
- Geology and Paleoclimatology Research
- Laser-Plasma Interactions and Diagnostics
- Diffusion and Search Dynamics
University of Warwick
2016-2025
London School of Economics and Political Science
2016-2025
The Open University
2015-2024
University of Toronto
2023
Sinai Health System
2023
Royal Hobart Hospital
2022
Laser Scan Engineering (United Kingdom)
2019-2021
California Institute of Technology
2021
British Antarctic Survey
2003-2020
Wake Forest University
2020
As climate change research becomes increasingly applied, the need for actionable information is growing rapidly. A key aspect of this requirement representation uncertainties. The conventional approach to representing uncertainty in physical aspects probabilistic, based on ensembles model simulations. In face deep uncertainties, known limitations are becoming apparent. An alternative thus emerging which may be called a 'storyline' approach. We define storyline as physically self-consistent...
Hadoop has become the de facto platform for large-scale data analysis in commercial applications, and increasingly so scientific applications. However, Hadoop's byte stream model causes inefficiencies when used to process that is commonly stored highly-structured, array-based binary file formats resulting limited scalability of applications science. We introduce Sci-Hadoop, a plugin allowing scientists specify logical queries over models. Sci-Hadoop executes as map/reduce programs defined...
Long memory plays an important role in many fields by determining the behaviour and predictability of systems; for instance, climate, hydrology, finance, networks DNA sequencing. In particular, it is to test if a process exhibiting long since that impacts accuracy confidence with which one may predict future events on basis small amount historical data. A major force development study was late Benoit B. Mandelbrot. Here, we discuss original motivation Mandelbrot’s influence this fascinating...
Abstract One of the most intriguing facets climate system is that it exhibits variability across all temporal and spatial scales; pronounced examples are temperature precipitation. The structure this variability, however, not arbitrary. Over certain ranges, can be described by scaling relationships in form power laws probability density distributions autocorrelation functions. These quantified exponents which measure how changes scales intensity with frequency occurrence. Scaling determines...
Introduced by the late Per Bak and his colleagues, self-organized criticality (SOC) has been one of most stimulating concepts to come out statistical mechanics condensed matter theory in last few decades, played a significant role development complexity science. SOC, more generally fractals power laws, have attacted much comment, ranging from very positive polemical. The other papers this special issue (Aschwanden et al, 2014; McAteer Sharma 2015) showcase considerable body observations...
Abstract The Sun exhibits a well-observed modulation in the number of spots on its disk over period about 11 years. From dawn modern observational astronomy, sunspots have presented challenge to understanding—their quasi-periodic variation number, first noted 175 years ago, has stimulated community-wide interest this day. A large techniques are able explain temporal landmarks, (geometric) shape, and amplitude sunspot “cycles,” however, forecasting these features accurately advance remains...
The power law dependence of the spectrum auroral indices, and in‐situ magnetic field observations in earth's geotail, may be evidence that coupled solar wind‐magnetospheric system exhibits scale free self organised criticality can to some extent described by avalanche models. In contrast, intensity of, time interval between, substorms both have well defined probability distributions with characteristic scales. We present results from a simple cellular automaton models avalanches one...
Fragile X syndrome (FXS) is a well-recognized form of inherited mental retardation, caused by mutation in the fragile retardation 1 (Fmr1) gene. The gene located on long arm chromosome and encodes protein (FMRP). Absence FMRP patients as well Fmr1 knockout (KO) mice results, among other changes, abnormal dendritic spine formation altered synaptic plasticity neocortex hippocampus. Clinical features FXS include cognitive impairment, anxiety, social interaction, motor coordination speech...
For both Levy flight and walk search processes we analyse the full distribution of first-passage first-hitting (or first-arrival) times. These are, respectively, times when particle moves across a point at some given distance from its initial position for first time, or it lands time. motions with their propensity long relocation events thus possibility to jump in space without actually hitting ("leapovers"), these two definitions lead significantly different results. We study time...
Quasilinear theories have been shown to well describe a range of transport phenomena in magnetospheric, space, astrophysical and laboratory plasma “weak turbulence” scenarios. It is known that the resonant diffusion quasilinear theory for case uniform background field may formally particle dynamics when electromagnetic wave amplitude growth rates are sufficiently “small”, bandwidth “large”. However, it important note given spectrum would be expected give rise transport, indeed apply...
The evolving subset of turbulent structures facilitates the energy transfer from large to small spatial scales, on average. Currently, it is not known how discontinuities that develop between these alter in solar wind. Quantifying scales essential explain apparent plasma heating during its advection through heliosphere. We analyse rate conditioned magnetic field line topology associated Magnetic classified using invariants gradient tensor constructed Cluster spacecraft configuration scale...
Independent validation of experimental results in the field systems research is a challenging task, mainly due to differences software and hardware computational environments. Recreating an environment that resembles original difficult time-consuming. In this paper we introduce _Popper_, convention based on set modern open source (OSS) development principles for generating reproducible scientific publications. Concretely, make case treating article as OSS project following DevOps approach...
Abstract The frequency and severity of heatwaves is expected to increase as the global climate warms. We apply crossing theory for first time determine heatwave properties solely from distribution daily observations without time‐correlation information. use Central England Temperature series quantify how simple increased occurrence higher temperatures makes (consecutive summer days with exceeding a threshold) more frequent intense. find an overall twofold threefold in activity since late...
Abstract Geomagnetic indices are routinely used to characterize space weather event intensity. The index is well resolved but only available over five solar cycles. extends 14 cycles highly discretized with poorly extremes. We parameterize extreme activity by the annual‐averaged top few percent of observed values, show that these exponentially distributed, and they track annual minima. This gives a 14‐cycle average 4% chance at least one great ( nT) storm 28% severe per year. At nT in given...
Abstract By obtaining the analytic signal of daily sunspot numbers since 1818 we construct a new solar cycle phase clock that maps each last 18 cycles onto single normalized 11 year epoch. This orders coronal activity and extremes aa index, which tracks geomagnetic storms at Earth's surface over 14 cycles. We identify geomagnetically quiet intervals are 40% cycle, ±2 π /5 in or ±2.2 years around minimum. Since 1868 only two severe ( >300 nT) one extreme >500 occurred intervals; 1–3%...
Connecting the different levels of hierarchy complexity in which climate models operate, and comparing assumptions that apply at each level, has led to much progress science. A particularly notable success was Klaus Hasselmann’s use Brownian motion inspire his linear Markovian stochastic energy balance model (EBM), history recently summarised by Watkins [2024]. Another informative, but lateral, connection comparison is between either studying through lens physical or doing so via...
Total Electron Content (TEC) is broadly used in characterizing ionospheric response to solar and geomagnetic activity. Understanding how TEC structures vary over time can help mitigate the risks of space weather events navigation communication systems. Global Ionospheric Maps (GIMs) produced by Jet Propulsion Laboratory (JPL) provide 20 years GNSS observations at a spatial resolution 1◦ × longitude/latitude temporal 15 minutes. We transform each these maps into coordinates...
In this paper we examine the claim that power law distribution of burst lifetimes in AE index is evidence magnetosphere a Self‐Organized Critical (SOC) system. To do compare lifetime distributions AU and |AL| indices with those υ B s ε solar wind input functions. We show for first time both are form an exponential cut‐off, consistent being SOC Furthermore, not significantly different to indices, indicating scale‐free property could arise from may be intrinsic magnetospheric discuss...
Abstract A number of influential assessments the economic cost climate change rely on just a small coupled climate–economy models. central feature these is their accounting epistemic uncertainty—that part our uncertainty stemming from inability to precisely estimate key model parameters, such as Equilibrium Climate Sensitivity. However, models fail account for aleatory uncertainty—the irreducible that remains even when true parameter values are known. We show how this second source in...