Preprints
Filtering by Subject: Physical Sciences and Mathematics
Inter-model spread in the pattern effect and its contribution to climate sensitivity in CMIP5 and CMIP6 models
Published: 2020-04-23
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Radiative feedbacks depend on the spatial patterns of sea-surface temperature (SST) and thus can change over time as SST patterns evolve – the so-called ‘pattern effect’. This study investigates inter-model differences in the magnitude of the pattern effect and how these differences contribute to the spread in the effective equilibrium climate sensitivity (ECS) within CMIP5 and CMIP6 models. [...]
Runout of rock avalanches limited by basal friction but controlled by fragmentation
Published: 2020-04-22
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
Rock avalanches display exceptionally long runouts, which are found to correlate with their volume and attributed to size dependent dynamic lowering of the effective basal friction. However, even for similar volumes, runouts are seen to span several orders of magnitude suggesting additional controlling factors. Here, we document experiments with analogue models of rock avalanches aimed at testing [...]
Using large-scale NO2 data from citizen science for air quality compliance and policy support
Published: 2020-04-21
Subjects: Earth Sciences, Engineering, Environmental Monitoring, Environmental Sciences, Life Sciences, Physical Sciences and Mathematics
Citizen science projects that monitor air quality have recently drastically expanded in scale. Projects involving thousands of citizens generate spatially dense datasets using low-cost passive samplers for nitrogen dioxide (NO2), which complement data from the sparse reference network operated by environmental agencies. However, there is a critical bottleneck in using these citizen-derived [...]
A seismic monitoring approach to detect and quantify river sediment mobilisation by steelhead redd-building activity
Published: 2020-04-20
Subjects: Earth Sciences, Geomorphology, Physical Sciences and Mathematics
The role of spawning salmonids in altering river bed morphology and sediment transport is significant yet poorly understood. This is due, in large part, to limitations in monitoring the redd-building process in a continuous and spatially extended way. A complementary approach may be provided through the use of a small seismic sensor network analysing the ground motion signals generated by the [...]
Lockdown caused by COVID-19 pandemic reduces air pollution in cities worldwide
Published: 2020-04-18
Subjects: Environmental Monitoring, Environmental Sciences, Life Sciences, Medicine and Health Sciences, Physical Sciences and Mathematics
Drastic measures such as lockdown taken by countries worldwide to contain spread of COVID-19 have influenced air pollution dynamics substantially, at a planetary scale. Several media reported the lockdown induced air pollution reduction based on quickly assembled satellite observations. However, a global-scale analysis of such reduction in air pollution backed by quality data collected from [...]
Palaeotidal atlas of the UK for the last 10,000 years
Published: 2020-04-18
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Over the past 10,000 years the UK has seen dramatic changes to its coastline due to sea-level rise. Past changes in sea level can be estimated from analysis of sedimentary deposits, including any microfossil assemblages found within. Once dated and the elevation is know, these data become sea level index points (SLIPs). In recreating past sea level in this way there is an implicit assumption of [...]
Lateral variability in strain along a mass-transport deposit (MTD) toewall: a case study from the Makassar Strait, offshore Indonesia
Published: 2020-04-18
Subjects: Earth Sciences, Geology, Geomorphology, Physical Sciences and Mathematics, Sedimentology
Contractional features characterise the toe domain of mass-transport deposits (MTDs). Their frontal geometry is typically classified as frontally-confined or frontally-emergent. However, it remains unclear how frontal emplacement style and contractional strain within an MTD can vary along strike. We use bathymetry and 3D seismic reflection data to investigate lateral variability of frontal [...]
Spontaneous Cyclogenesis without Radiative and Surface-Flux Feedbacks
Published: 2020-04-18
Subjects: Atmospheric Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Tropical cyclones (TCs) are among the most intense and feared storms in the world. What physical processes lead to cyclogenesis remains the most mysterious aspect of TC physics. Here, we study spontaneous TC genesis in rotating radiative-convective equilibrium using cloud-resolving simulations over an f-plane with constant sea-surface temperature. Previous studies proposed that spontaneous TC [...]
Modelling high-frequency seismograms at ocean bottom seismometers: effects of heterogeneous structures on source parameter estimation for small offshore earthquakes and shallow low-frequency tremors
Published: 2020-04-18
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
The source characteristics of offshore seismic events, especially regular (or fast) and slow earthquakes, can provide key information on their source physics and frictional conditions at the plate boundary. Due to strong three-dimensional heterogeneities in offshore regions, such as those relating to seawater, accretionary prism, and small-scale velocity heterogeneity, conventional methods using [...]
Downscaling digital soil maps using electromagnetic induction and aerial imagery
Published: 2020-04-17
Subjects: Earth Sciences, Physical Sciences and Mathematics, Soil Science
Coarse-resolution soil maps at regional to national extents are often inappropriate for mapping intra-field variability. At the same time, sensor data, such as electromagnetic induction measurements and aerial imagery, can be highly useful for mapping soil properties that correlate with electrical conductivity or soil color. However, maps based on these data nearly always require calibration with [...]
Flow directions of rivers are set by the mantle
Published: 2020-04-17
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Large rivers play crucial roles in determining loci of civilisation, natural resources and biodiversity. The positions of their mouths control nutrient and sediment supply to oceans. The paths that rivers take across the Earth’s surface varies considerably with scale. For example, at large scales big North American rivers (e.g. Mississippi, Colorado, Columbia) have simple flow paths that can be [...]
Lateral variations in lower crustal strength control the temporal evolution of mountain ranges: examples from south-east Tibet
Published: 2020-04-17
Subjects: Earth Sciences, Geochemistry, Geomorphology, Geophysics and Seismology, Physical Sciences and Mathematics, Tectonics and Structure
Controversy surrounds the rheology of the continental lithosphere, and how it controls the evolution and behaviour of mountain ranges. In this study, we investigate the effect of lateral contrasts in the strength of the lower crust, such as those between cratonic continental interiors and weaker rocks in the adjacent deforming regions, on the evolution of topography. We combine numerical [...]
Evaluating UK natural hazards: the national risk assessment
Published: 2020-04-15
Subjects: Earth Sciences, Environmental Indicators and Impact Assessment, Environmental Sciences, Other Environmental Sciences, Physical Sciences and Mathematics
Despite its relatively temperate climate and stable geography, natural hazards present multiple risks to human activity in the UK. These range from small-scale local occurrences, such as landslides, through regional incidents, such as flooding, to major high impact, low probability events, such as space weather. The impacts of such hazards can be wide-ranging but may include disruption to [...]
Do atmospheric plastics act as fomites for novel viruses?
Published: 2020-04-15
Subjects: Atmospheric Sciences, Civil and Environmental Engineering, Engineering, Environmental Health and Protection, Environmental Sciences, Life Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Plastic particles are ubiquitous in various environmental compartments, the atmosphere being the least explored compartment in terms of plastic pollution. The way that atmospheric plastics affect the biological systems has not yet been explored when compared to aquatic ecosystems. There are many speculated human health impacts, one definite and direct impact of atmospheric plastics would be [...]
Forming a Mogi Doughnut in the years prior to and immediately before the the 2014 M8.1 Iquique, Northern Chile Earthquake
Published: 2020-04-15
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Asperities are patches where the fault surfaces stick until they break in earthquakes. Locating asperities and understanding their causes in subduction zones is challenging because they are generally located offshore. We use seismicity, inter- and co-seismic slip, and the residual gravity field to map the asperity responsible for the 2014 M8.1 Iquique Chile earthquake. Until two weeks before the [...]