Preprints
Filtering by Subject: Oceanography and Atmospheric Sciences and Meteorology
Heavy rainfall in Paraguay during the 2015-2016 austral summer: causes and sub-seasonal-to-seasonal predictive skill
Published: 2019-02-11
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Climate, Earth Sciences, Engineering, Environmental Engineering, Environmental Sciences, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Water Resource Management
During the austral summer 2015/16, severe flooding displaced over 170 000 people on the Paraguay River system in Paraguay, Argentina, and southern Brazil. These floods were driven by repeated heavy rainfall events in the lower Paraguay River basin. Alternating sequences of enhanced moisture inflow from the South American low-level jet and local convergence associated with baroclinic systems were [...]
The Urban Heat Island (UHI) is a major source of uncertainty in projections of population-weighted surface temperature under climate change.
Published: 2019-02-06
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Rising global mean temperatures and an increase in the fraction of the population living in urban areas is leading to a number of grand challenges. Contrasting area-weighted and population-weighted trends in an ensemble of CMIP5 climate model simulations under a range of climate and population change scenarios (RCPs and SSPs) shows that population-weighted changes in future surface temperature [...]
Factor Analysis by R Programming to Assess Variability Among Environmental Determinants of the Mariana Trench
Published: 2019-01-28
Subjects: Computer Sciences, Earth Sciences, Education, Engineering, Environmental Monitoring, Environmental Sciences, Environmental Studies, Geographic Information Sciences, Geography, Geology, Geomorphology, Geophysics and Seismology, Graphics and Human Computer Interfaces, Life Sciences, Marine Biology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Other Geography, Other Oceanography and Atmospheric Sciences and Meteorology, Physical and Environmental Geography, Physical Sciences and Mathematics, Programming Languages and Compilers, Remote Sensing, Science and Mathematics Education, Sedimentology, Social and Behavioral Sciences, Spatial Science, Tectonics and Structure, Water Resource Management
The aim of this work is to identify main impact factors affecting variations in the geomorphology of the Mariana Trench which is the deepest place of the Earth, located in the west Pacific Ocean: steepness angle and structure of the sediment compression. The Mariana Trench presents a complex ecosystem with highly interconnected factors: geology (sediment thickness and tectonics including four [...]
Hierarchical Cluster Analysis by R language for Pattern Recognition in the Bathymetric Data Frame: a Case Study of the Mariana Trench, Pacific Ocean
Published: 2019-01-25
Subjects: Applied Statistics, Earth Sciences, Environmental Education, Environmental Monitoring, Environmental Sciences, Environmental Studies, Geographic Information Sciences, Geography, Geology, Geomorphology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Other Oceanography and Atmospheric Sciences and Meteorology, Other Statistics and Probability, Physical and Environmental Geography, Physical Sciences and Mathematics, Social and Behavioral Sciences, Spatial Science, Statistics and Probability, Tectonics and Structure
The geographic focus of the current study Mariana trench, the deepest point of the Earth located in the west Pacific Ocean. Mariana trench has unique structure and features formed in the complex process of the trench development. There is a range of the environmental factors affecting trench structure and functioning: bathymetry, geography, geology and tectonics. Current research aimed to study [...]
Dynamics of ITCZ width: Ekman processes, non-Ekman processes and links to sea-surface temperature
Published: 2019-01-22
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The dynamical processes controlling the width of the intertropical convergence zone (ITCZ) are investigated using idealized simulations. ITCZ width is defined in terms of boundary-layer vertical velocity. The tropical boundary layer is approximately in Ekman balance suggesting that wind stress places a strong constraint on ITCZ width. A scaling based on Ekman balance predicts that ITCZ width is [...]
A statistics-based reconstruction of high-resolution global terrestrial climate for the last 800,000 years
Published: 2019-01-18
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Statistical Models, Statistics and Probability
Curated global climate data have been generated from climate model outputs for the last 120,000 years, whereas reconstructions going back even further have been lacking due to the high computational cost of climate simulations. Here, we present a statistically-derived global terrestrial climate dataset for every 1,000 years of the last 800,000 years. It is based on a set of linear regressions [...]
Utilising the flexible generation potential of tidal range power plants to optimise economic value
Published: 2019-01-08
Subjects: Civil and Environmental Engineering, Computational Engineering, Engineering, Hydraulic Engineering, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tidal range renewable power plants have the capacity to deliver predictable energy to the electricity grid, subject to the known variability of the tides. Tidal power plants inherently feature advantages that characterise hydro-power more generally, including a lifetime exceeding alternative renewable energy technologies and relatively low Operation & Maintenance costs. Nevertheless, the [...]
Buoyancy driven distributed chaos and ensemble weather forecasting
Published: 2019-01-04
Subjects: Atmospheric Sciences, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
It is shown, using results of direct numerical simulations, that strong thermal convection in horizontal layer and on a hemisphere can be well described by the distributed chaos approach with the stretched exponential kinetic energy spectrum. Two relevant cases: the vorticity and helicity dominated distributed chaos, have been considered. The results obtained with the Weather Research and [...]
A test case for application of convolutional neural networks to spatio-temporal climate data: Re-identifying clustered weather patterns
Published: 2019-01-01
Subjects: Applied Mathematics, Computer Sciences, Earth Sciences, Engineering, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Planetary Sciences
Convolutional neural networks (CNNs) can potentially provide powerful tools for classifying and identifying patterns in climate and environmental data. However, because of the inherent complexities of such data, which are often spatio-temporal, chaotic, and non-stationary, the CNN algorithms must be designed/evaluated for each specific dataset and application. Yet to start, CNN, a supervised [...]
Comparing the Euro 2k reconstruction to a regional climate model simulation
Published: 2018-12-20
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics
We do not expect simulations and reconstructions of past climate change to agree on the exact evolution of past climate variations. Simulations with sophisticated climate models present spatially discrete but complete estimates, which are consistent relative to the implemented physics and their uncertain forcing data. Reconstruction methods statistically infer past changes from natural archives [...]
Attributing Historical and Future Evolution of Radiative Feedbacks to Regional Warming Patterns using a Green’s Function Approach: The Preeminence of the Western Pacific
Published: 2018-12-18
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Global radiative feedbacks have been found to vary in global climate model (GCM) simulations. Atmospheric GCMs (AGCMs) driven with historical patterns of sea-surface temperatures (SST) and sea-ice concentrations produce radiative feedbacks that trend toward more negative values, implying low climate sensitivity, over recent decades. Freely-evolving coupled GCMs driven by increasing CO2 produce [...]
Intensity-Duration-Frequency curves at the global scale
Published: 2018-12-18
Subjects: Civil and Environmental Engineering, Earth Sciences, Engineering, Environmental Sciences, Hydraulic Engineering, Hydrology, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Water Resource Management
Intensity-Duration-Frequency (IDF) curves usefully quantify extreme precipitation over various durations and return periods for engineering design. Unfortunately, sparse, infrequent or short observations hinder the creation of robust IDF curves in many locations. This paper presents the first global, multi-temporal (1 to 360 hours) dataset of Generalized Extreme Value (GEV) parameters at 31 km [...]
Separating the impact of individual land surface properties on the terrestrial surface energy budget in both the coupled and un-coupled land-atmosphere system
Published: 2018-12-12
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Changes in the land surface can drive large responses in the atmosphere on local, regional, and global scales. Surface properties control the partitioning of energy within the surface energy budget to fluxes of shortwave and longwave radiation, sensible and latent heat, and ground heat storage. Changes in surface energy fluxes can impact the atmosphere across scales through changes in [...]
Extreme weather events in early Summer 2018 connected by a recurrent hemispheric wave-7 pattern.
Published: 2018-11-28
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The summer of 2018 witnessed a number of extreme weather events such as heatwaves in North America, Western Europe and the Caspian Sea region and rainfall extremes in South-East Europe and Japan that occurred near-simultaneously. Here we show that these extremes were connected by an amplified hemisphere-wide wavenumber 7 circulation pattern. We show that this pattern constitutes a teleconnection [...]
Analysis of atmospheric thermodynamics using the R package aiRthermo
Published: 2018-11-26
Subjects: Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This is a non-peer reviewed preprint submitted to EarthArxiv. It corresponds to the version initially submitted to Computers and Geosciences corresponding to final paper "Analysis of atmospheric thermodynamics using the R package aiRthermo", describing a new package for R which has been designed for computations of quantities related to atmospheric thermodynamics. The paper was finally accepted [...]