Preprints
There are 7994 Preprints listed.
Critical Review of Polyphosphate and Polyphosphate Accumulating Organisms for Agricultural Water Quality Management
Published: 2018-12-03
Subjects: Agriculture, Biogeochemistry, Earth Sciences, Environmental Microbiology and Microbial Ecology Life Sciences, Environmental Sciences, Life Sciences, Microbiology, Natural Resources Management and Policy, Physical Sciences and Mathematics, Soil Science, Water Resource Management
Despite ongoing management efforts, phosphorus (P) loading from agricultural landscapes continues to impair water quality. Wastewater treatment research has enhanced our knowledge of microbial mechanisms influencing P cycling, especially regarding microbes known as polyphosphate accumulating organisms (PAOs) that store P as polyphosphate (polyP) under oxic conditions and release P under anoxic [...]
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 [...]
Episodic fluid flow in an active fault
Published: 2018-11-30
Subjects: Earth Sciences, Geology, Hydrology, Physical Sciences and Mathematics, Tectonics and Structure
We present a 250 ka record of episodic fluid flow along the Malpais fault which hosts the Beowawe hydrothermal system, Nevada, USA. The history of fluid flow was quantified using a novel combination of the apatite (U-Th)/He (AHe) thermochronometer and a model of the thermal effects of fluid flow. Samples show partial resetting of the AHe thermochronometer in a 40 m wide zone around the normal [...]
Exceptionally large block-and-ash flows: a detailed study of the 2005 and 2010 eruption deposits of Shiveluch volcano
Published: 2018-11-27
Subjects: Earth Sciences, Physical Sciences and Mathematics, Volcanology
Two of the largest known historic block-and-ash flow (BAF) fields are located on Shiveluch volcano, Kamchatka. The deposits were produced during retrogressive and pulsatory dome collapse events that occurred over 6-9 hour-long eruptions on 27-28 February 2005 and 27 October 2010. The BAFs that were produced by these partial dome collapse events extend up to 19 km from the dome and inundate areas [...]
Methane bursts as a trigger for intermittent lake-forming climates on post-Noachian Mars
Published: 2019-01-01
Subjects: Astrophysics and Astronomy, Earth Sciences, Geology, Physical Sciences and Mathematics, The Sun and the Solar System
Lakes existed on Mars later than 3.6 billion years ago, according to sedimentary evidence for deltaic deposition. The observed fluvio-lacustrine deposits suggest that individual lake-forming climates persisted for at least several thousand years (assuming dilute flow). But the lake watersheds’ little weathered soils indicate a largely dry climate history, with intermittent runoff events. Here we [...]
Persistent or repeated surface habitability on Mars during the Late Hesperian - Amazonian
Published: 2019-01-01
Subjects: Astrophysics and Astronomy, Earth Sciences, Geology, Physical Sciences and Mathematics, The Sun and the Solar System
Large alluvial fan deposits on Mars record relatively recent habitable surface conditions (≲3.5 Ga, Late Hesperian – Amazonian). We find net sedimentation rate <(4-8) μm/yr in the alluvial-fan deposits, using the frequency of craters that are interbedded with alluvial fan deposits as a fluvial-process chronometer. Considering only the observed interbedded craters sets a lower bound of >20 [...]
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 [...]
Imbalance in the modern hydrologic budget of topographic catchments along the western slope of the Andes (21–25 S)
Published: 2018-11-20
Subjects: Earth Sciences, Hydrology, Physical Sciences and Mathematics
Rates of water discharge often exceed groundwater recharge in arid catchments. This apparent mass imbalance within a catchment may be reconciled through either regional-scale groundwater flow between topographic drainages and/or the draining of stored groundwater recharged during pluvial periods. We investigate discrepancies in the modern hydrologic budget of catchments along the west flank of [...]
Joint inversion of co-seismic and early post-seismic slip: Application to the 2009 Mw6.3 LAquila earthquake, Central Italy
Published: 2018-11-20
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Geodetic data provide static information on the displacement of the surface of the Earth, and allow for a detailed analysis of earthquake characteristics. Yet, geodetic data are generally characterized by either a good temporal or a good spatial resolution, but rarely both. This lack of resolution affects our understanding of the evolution of seismic and aseismic processes. Here, we propose a [...]
Quantifying relationships between environmental factors and power dissipation on the most prolific days in the largest tornado ‘outbreaks’
Published: 2018-11-20
Subjects: Earth Sciences, Other Earth Sciences, Physical Sciences and Mathematics
An outbreak can occur as a single day or a multi-day event characterized by many tornadoes associated with specific regional scale environmental factors. The objective of this research is to quantify the relationship between environmental factors and tornado activity using big tornado days that occur in the largest multi-day groups in the United States. First, the largest groups across space and [...]
Applications of Deep Learning to Ocean Data Inference and Sub-Grid Parameterisation
Published: 2018-11-20
Subjects: Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Oceanographic observations are limited by sampling rates, while ocean models are limited by finite resolution and high viscosity and diffusion coefficients. Therefore both data from observations and ocean models lack information at small-scales. Methods are needed to either extract information, extrapolate, or up-scale existing oceanographic datasets, to account for the unresolved physical [...]
Changes in global groundwater organic carbon driven by climate change and urbanization
Published: 2018-11-21
Subjects: Environmental Sciences, Physical Sciences and Mathematics
Rapid urban growth is increasing demand for potable groundwater. Dissolved organic carbon (DOC) is a major control of groundwater potability and treatment costs. We hypothesize that climate change and urbanization will not only decrease groundwater availability, but also its quality. Here, we summarize global groundwater DOC data (n = 6781) to identify its drivers and predict future changes. Our [...]
SSPipeline: A pipeline for estimating and characterizing uncertainty in coastal storm surge levels
Published: 2018-10-22
Subjects: Computer Sciences, Engineering, Numerical Analysis and Scientific Computing, Physical Sciences and Mathematics, Statistical Models, Statistics and Probability
Effective management of coastal risks demands projections of flood hazards that account for a wide variety of potential sources of uncertainty. Two typical approaches for estimating flood hazards include (1) direct physical process-based modeling of the storms themselves and (2) statistical modeling of the distributions and relevant characteristics of extreme sea level events. Recently, flexible [...]
Calibration of astigmatic particle tracking velocimetry based on generalized Gaussian feature extraction
Published: 2018-11-20
Subjects: Artificial Intelligence and Robotics, Computer Sciences, Earth Sciences, Engineering, Fluid Dynamics, Hydrology, Life Sciences, Physical Sciences and Mathematics, Physics
Flow and transport in porous media are driven by pore scale processes. Particle tracking in transparent porous media allows for the observation of these processes at the time scale of ms. We demonstrate an application of defocusing particle tracking using brightfield illumination and a CMOS camera sensor. The resulting images have relatively high noise levels. To address this challenge, we [...]
Earth Science is Ready for Preprints: The First Year of EarthArXiv
Published: 2018-11-13
Subjects: Earth Sciences, Education, Physical Sciences and Mathematics
Preprints — scholarly papers that precede publication in a peer-reviewed journal — speed the delivery and accessibility of academic work and lead to faster reuse by the scientific community, as evidenced by rapid citations and social media discussions. In the past year, EarthArXiv has emerged as a community-led initiative devoted to open scholarly communication. EarthArXiv became the first [...]