Preprints
There are 5493 Preprints listed.
Reconstruction of satellite time series with a dynamic smoother
Published: 2021-08-20
Subjects: Environmental Monitoring, Longitudinal Data Analysis and Time Series
Time series reconstruction methods---used to generate gap-free time series of satellite observations---were historically designed for sensors with frequent image acquisitions. Since 2008, interest in leveraging time series methods has shifted from sensors such as AVHRR and MODIS to Landsat because of free, higher-resolution data availability and improved access to high-performance compute [...]
Sea surface salinity subfootprint variability from a global high-resolution model
Published: 2021-08-20
Subjects: Oceanography
Subfootprint variability (SFV) is variability at a spatial scale smaller than the footprint of a sat-ellite, and cannot be resolved by satellite observations. It is important to quantify and understand as it contributes to the error budget for satellite data. The purpose of this study is to estimate the SFV for sea surface salinity (SSS) satellite observations. This is done using a [...]
The Optimal Correlation Detector?
Published: 2021-08-19
Subjects: Earth Sciences, Geophysics and Seismology, Physical Sciences and Mathematics
Correlation detectors are now used routinely in seismology to detect occurrences of signals bearing close resemblance to a reference waveform. They facilitate the detection of low-amplitude signals in significant background noise that may elude detection using energy detectors, and they associate a detected signal with a source location. Many seismologists use the fully normalized correlation [...]
Root foraging alters global patterns of ecosystem legacy from climate perturbations
Published: 2021-08-19
Subjects: Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology
The response of terrestrial ecosystems to climate perturbations typically persist longer than the timescale of the forcing, a phenomenon that is broadly referred to as ecosystem legacy. Understanding the strength of legacy is critical for predicting ecosystem sensitivity to climate extremes and the extent to which persistent changes in land surface-atmosphere exchange might feedback onto the [...]
Data requirements to tackle global deforestation through mandatory due diligence
Published: 2021-08-19
Subjects: Environmental Indicators and Impact Assessment, Natural Resources Management and Policy, Sustainability
The world’s forests are highly threatened, mainly by agricultural expansion, driving biodiversity loss and greenhouse gas emissions, and disproportionately impacting rights and livelihoods of indigenous peoples and local communities. Zero-deforestation voluntary commitments to address deforestation have not significantly reversed deforestation and have made even less progress in related human [...]
Safety and Belonging in the Field: A Checklist for Educators
Published: 2021-08-19
Subjects: Atmospheric Sciences, Biogeochemistry, Climate, Cosmochemistry, Earth Sciences, Education, Environmental Education, Environmental Health and Protection, Environmental Indicators and Impact Assessment, Environmental Monitoring, Environmental Sciences, Environmental Studies, Fresh Water Studies, Geochemistry, Geographic Information Sciences, Geography, Geology, Geomorphology, Geophysics and Seismology, Glaciology, Higher Education, Human Geography, Hydrology, Life Sciences, Meteorology, Mineral Physics, Natural Resource Economics, Natural Resources and Conservation, Natural Resources Management and Policy, Nature and Society Relations, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Oil, Gas, and Energy, Other Earth Sciences, Other Environmental Sciences, Other Geography, Other Oceanography and Atmospheric Sciences and Meteorology, Other Planetary Sciences, Outdoor Education, Paleobiology, Paleontology, Physical and Environmental Geography, Physical Sciences and Mathematics, Planetary Biogeochemistry, Planetary Geochemistry, Planetary Geology, Planetary Geomorphology, Planetary Geophysics and Seismology, Planetary Glaciology, Planetary Hydrology, Planetary Mineral Physics, Planetary Sciences, Planetary Sedimentology, Remote Sensing, Sedimentology, Social and Behavioral Sciences, Soil Science, Spatial Science, Speleology, Stratigraphy, Sustainability, Tectonics and Structure, Volcanology, Water Resource Management
Ensuring taught fieldwork is a positive, generative, collective, and valuable experience for all participants requires considerations beyond course content. To guarantee safety and belonging, participants’ identities (backgrounds and protected characteristics) must be considered as a part of fieldwork planning and implementation. Furthermore, getting fieldwork right is an important step in [...]
Dissolution precipitation creep as a process for the strain localisation in mafic rocks
Published: 2021-08-17
Subjects: Earth Sciences, Geochemistry, Tectonics and Structure
Unaltered mafic rocks consist of mechanically strong minerals (e.g. pyroxene, plagioclase and garnet) that can be deformed by crystal plastic mechanisms only at high temperatures (>800°C). Yet, many mafic rocks do show extensive deformation by non-brittle mechanisms when they have been subjected to lower temperature conditions. In such cases, the deformation typically is assisted by mineral [...]
Seasonality in Arctic Warming Driven By Sea Ice Effective Heat Capacity
Published: 2021-08-17
Subjects: Physical Sciences and Mathematics
Arctic surface warming under greenhouse gas forcing peaks in early winter and reaches its minimum during summer in both observations and model projections. Many mechanisms have been proposed to explain this seasonal asymmetry, but disentangling these processes remains a challenge in the interpretation of general circulation model (GCM) experiments. To isolate these mechanisms, we use an idealized [...]
Irreducible Southern Ocean State Uncertainty due to Global Ocean Initial Conditions
Published: 2021-08-17
Subjects: Oceanography and Atmospheric Sciences and Meteorology
How do ocean initial conditions impact historical and future climate projections in Earth system models? To answer this question, we use the 50-member Canadian Earth System Model (CanESM2) large ensemble, in which individual ensemble members are initialized using a strategic combination of different oceanic initial states and different atmospheric perturbations. We show that global ocean heat [...]
Post-LGM glacial retreat and Early Holocene monsoon intensification drives aggradation in the interiors of the Kashmir Himalaya
Published: 2021-08-15
Subjects: Earth Sciences
Understanding the response of glaciated catchments to climate change is crucial for assessing sediment transport from the high-elevation, semi-arid sectors in the Himalaya. The fluvioglacial sediments stored in the semi-arid Padder valley in the Kashmir Himalaya record valley aggradation during ~20 -10 ka. We relate the initial stage of valley aggradation to increased sediment supply from the [...]
Dynamic Compressive Strength and Fragmentation in Sedimentary and Metamorphic Rocks
Published: 2021-08-15
Subjects: Mechanics of Materials, Tectonics and Structure
Brittle deformation at high strain rates results in intense fragmentation and rock pulverisation. For rocks, the critical strain rate at which this behaviour occurs is ~10^2 s-1. The mechanical properties of rocks at these strain rates can also be very different from their quasi-static properties. Deformation of rocks at these strain rates is uncommon in nature but can occur during fault rupture, [...]
Does ENSO significantly affect rice production in Indonesia? A preliminary study using computational time-series approach
Published: 2021-08-15
Subjects: Climate, Environmental Sciences, Physical Sciences and Mathematics
ENSO is a phenomenon that is suspected to influence rice production in Indonesia. In this study, we try to find a direct correlation between ENSO and rice production in this region by using various latest computational time series methods, such as Dynamic Time Warping, Wavelet Coherence, and Bayesian Structural Time Series to quantify the statistical relationship between the Multivariate ENSO [...]
Transport and Fate of All-Time Released Plastics in the Global Ocean
Published: 2021-08-14
Subjects: Environmental Sciences, Other Environmental Sciences
Mismanaged plastics accumulate in oceans and threaten marine life. About 40 million tonnes of plastics have reached the oceans, where their fate remains unclear. To track the sources, sinks, sizes, and age of all-time released plastics, we developed a new mechanistic model and synthesized decades of measurements. We find that Asian plastics are the largest contributor (76%) to marine plastics by [...]
The role of sediment subduction and buoyancy on subduction dynamics and geometry
Published: 2021-08-14
Subjects: Earth Sciences, Physical Sciences and Mathematics
Subducted sediments are thought to lubricate the subduction interface and promote faster plate speeds. However, global observations are not clear-cut on the relationship between the amount of sediments and plate motion. Sediments are also thought to influence slab dip, but variations in subduction geometry depend on multiple factors. Here we use 2D thermomechanical models to explore how sediments [...]
The early diversification of ray-finned fishes (Actinopterygii): hypotheses, challenges and future prospects
Published: 2021-08-14
Subjects: Paleobiology, Paleontology
Actinopterygii are the most speciose living vertebrate clade, and study of fossil members during their Palaeozoic rise to dominance has a long history of descriptive work. Although research interest into Palaeozoic actinopterygians has increased in recent years, broader patterns of diversity and diversity dynamics remain critically understudied. Past studies have investigated macroevolutionary [...]