Preprints
Filtering by Subject: Statistics and Probability
Seasonal impact-based mapping of compound hazards
Published: 2020-06-17
Subjects: Applied Mathematics, Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Hydrology, Mathematics, Multivariate Analysis, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistics and Probability
Impact-based, seasonal mapping of compound hazards is proposed. It is pragmatic, identifies phenomena to drive the research agenda, produces outputs relevant to stakeholders, and could be applied to many hazards globally. Illustratively, flooding and wind damage can co-occur, worsening their joint impact, yet where wet and windy seasons combine has not yet been systematically mapped. Here, [...]
Large model parameter and structural uncertainties in global projections of urban heat waves
Published: 2020-06-10
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Computer Sciences, Earth Sciences, Engineering, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Risk Analysis, Statistics and Probability
Urban heat waves (UHWs) are strongly associated with socioeconomic impacts. Reliable projections of these extremes are pressingly needed for local actions in the context of extreme event preparedness and mitigation. Such information, however, is not available because current multi-model projections largely lack a representation of urban areas. Here, we use a newly-developed urban climate emulator [...]
Observation-based Simulations of Humidity and Temperature Using Quantile Regression
Published: 2020-05-28
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistics and Probability
The human impacts of changes in heat events depend on changes in the joint behavior of temperature and humidity. Little is currently known about these complex joint changes, either in observations or projections from general circulation models (GCMs). Further, GCMs do not fully reproduce the observed joint distribution, implying a need for simulation methods that combine information from GCMs [...]
A newly reconciled data set for identifying sea level rise and variability in Dublin Bay
Published: 2020-05-27
Subjects: Applied Statistics, Climate, Earth Sciences, Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Other Life Sciences, Physical Sciences and Mathematics, Planetary Sciences, Statistics and Probability
We provide an updated sea level dataset for Dublin for the period 1938 to 2016 at yearly resolution. Using a newly collated sea level record for Dublin Port, as well as two nearby tide gauges at Arklow and Howth Harbour, we perform data quality checks and calibration of the Dublin Port record by adjusting the biased high water level measurements that affect the overall calculation of mean sea [...]
Probabilistic soil moisture dynamics of water- and energy-limited ecosystems
Published: 2020-05-17
Subjects: Agriculture, Agronomy and Crop Sciences Life Sciences, Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Forest Sciences, Hydrology, Life Sciences, Physical Sciences and Mathematics, Plant Sciences, Statistical Models, Statistics and Probability
This paper presents an extension of the stochastic ecohydrological model for soil moisture dynamics at a point of Rodriguez-Iturbe et al. (1999) and Laio et al. (2001). In the original model, evapotranspiration is a function of soil moisture and vegetation parameters, so that the model is suitable for water-limited environments. Our extension introduces a dependence on maximum evapotranspiration [...]
Three Common Statistical Missteps We Make in Reservoir Characterization
Published: 2020-05-11
Subjects: Chemical Engineering, Earth Sciences, Engineering, Geology, Petroleum Engineering, Physical Sciences and Mathematics, Statistical Methodology, Statistics and Probability
Reservoir characterization analysis resulting from incorrect applications of statistics can be found in the literature, particularly in applications where integration of various disciplines is needed. Here, we look at three misapplications of ordinary least squares linear regression (LSLR) and show how they can lead to poor results and offer better alternatives, where available. The issues are [...]
Comparison of permeability predictions on cemented sandstones with physics-based and machine learning approaches
Published: 2020-02-06
Subjects: Chemical Engineering, Earth Sciences, Engineering, Hydrology, Multivariate Analysis, Petroleum Engineering, Physical Sciences and Mathematics, Statistics and Probability
Permeability prediction has been an important problem since the time of Darcy. Most approaches to solve this problem have used either idealized physical models or empirical relations. In recent years, machine learning (ML) has led to more accurate and robust, but less interpretable empirical models. Using 211 core samples collected from 12 wells in the Garn Sandstone from the North Sea, this [...]
Evaluating the INLA-SPDE approach for Bayesian modeling of earthquake damages from geolocated cluster data
Published: 2020-01-27
Subjects: Physical Sciences and Mathematics, Statistical Models, Statistics and Probability
Modeled damage estimates are an important source of information in the hours to weeks following major earthquake disasters, but often lack sufficient spatial resolution for highlighting specific areas of need. Using damage assessment data from the 2015 Gorkha, Nepal Earthquake, this paper evaluates a Bayesian spatial model (INLA-SPDE) for interpolating geolocated damage survey data onto 1 km2 [...]
Advanced ML and AI Approaches for Proxy-based Optimization of CO2-Enhanced Oil Recovery in Heterogeneous Clastic Reservoirs
Published: 2019-12-04
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Design of Experiments and Sample Surveys, Earth Sciences, Multivariate Analysis, Other Earth Sciences, Physical Sciences and Mathematics, Programming Languages and Compilers, Statistics and Probability
Constructing a simpler model to represent a complex reservoir simulation that will be employed to define the optimum future development plans have been achieved through the use of different simulation techniques that include EOS-compositional reservoir simulation, Proxy Modeling as well as Design of Experiments. Once reliable history matching was achieved, the key five operational decision [...]
A 2,000-year Bayesian NAO reconstruction from the Iberian Peninsula
Published: 2019-11-27
Subjects: Applied Statistics, Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics, Statistics and Probability
The North Atlantic Oscillation (NAO) is the major atmospheric mode that controls winter European climate variability because its strength and phase determine regional temperature, precipitation and storm tracks. The NAO spatial structure and associated climatic impacts over Europe are not stationary making it crucial to understanding its past evolution in order to improve the predictability of [...]
Deep Unsupervised 4D Seismic 3D Time-Shift Estimation with Convolutional Neural Networks
Published: 2019-10-31
Subjects: Applied Statistics, Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics, Statistics and Probability
We present a novel 3D warping technique for the estimation of 4D seismic time-shift. This unsupervised method provides a diffeomorphic 3D time shift field that includes uncertainties, therefore it does not need prior time-shift data to be trained. This results in a widely applicable method in time-lapse seismic data analysis. We explore the generalization of the method to unseen data both in the [...]
Controls on the development and termination of failed continental rifts: Insights from the crustal structure and rifting style of the North Sea via ambient noise tomography
Published: 2019-09-21
Subjects: Applied Mathematics, Computer Sciences, Earth Sciences, Geophysics and Seismology, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Physical Sciences and Mathematics, Probability, Statistics and Probability
The mid to lower crust plays an important role in rift initiation and evolution, particularly when large scale sutures and/or terrane boundaries are present. These inherited features can focus strain or act as inhibitors to extensional deformation. Ancient tectonic features are known to exist beneath the iconic failed rift system of the North Sea making it the ideal location to investigate the [...]
Paradoxical impact of sprawling intra-Urban Heat Islets: Reducing mean surface temperatures while enhancing local extremes
Published: 2019-09-09
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Life Sciences, Physical Sciences and Mathematics, Statistics and Probability
Cities are at the forefront of climate change impacts and face a growing burden of adaptation to ensuing natural hazards. Extreme heat is a particularly challenging hazard as persistent heatwaves are locally exacerbated by the Urban Heat Island (UHI) effect. As a result, there is an increasing scientific interest in the influence of diverse urban morphologies on UHI. However, as the temperatures [...]
Emergent self-similarity and scaling properties of fractal intra-Urban Heat Islets for diverse global cities
Published: 2019-09-02
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Physical Sciences and Mathematics, Statistics and Probability
Urban areas experience elevated temperatures due to the Urban Heat Island (UHI) effect. However, temperatures within cities vary considerably and their spatial heterogeneity is not well characterized. Here, we use Land Surface Temperature (LST) of 78 global cities to show that the Surface UHI (SUHI) is fractal. We use percentile-based thermal thresholds to identify heat clusters emerging within [...]
A mechanistic erosion model for cosmogenic nuclide inheritance in fluvial single-clast exposure ages
Published: 2019-08-06
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Statistics and Probability, Tectonics and Structure
Terrestrial cosmogenic nuclides (TCNs), produced by the bombardment of Earth’s surface by cosmic rays, are widely used for age-dating and pacing surface processes. Sediments carry an inherited TCN concentration, useful for quantifying erosion and transport rates, but that must be subtracted when age-dating sedimentary landforms, such as alluvial fans. Here we present a mechanistic model of [...]