Preprints
Filtering by Subject: Environmental Monitoring
Carcass locations implicate cyanobacterial toxicity in a mass elephant mortality event in Botswana
Published: 2024-05-07
Subjects: Climate, Environmental Microbiology and Microbial Ecology Life Sciences, Environmental Monitoring, Physical and Environmental Geography, Remote Sensing, Spatial Science, Terrestrial and Aquatic Ecology
The 2020 mass mortality of 350 African elephants (Loxodonta africana) in Botswana sparked global concern. These deaths have been linked to cyanobacterial toxins (cyanotoxins) in local watering holes (pans), but evidence remains inconclusive. Our study presents the first detailed spatial analysis that explores the relationship between the ecohydrology of 3,389 regional pans with the locations of [...]
Global patterns of commodity-driven deforestation and associated carbon emissions
Published: 2024-04-18
Subjects: Environmental Monitoring, Natural Resource Economics, Statistical Models, Sustainability
Achieving global climate and biodiversity targets and ensuring future food security will require halting agriculture-driven deforestation. Accurate data on the commodities driving deforestation across time and space is crucial for informing policy development, implementation and evaluation. However, such information is currently hampered by limited and heterogeneous data availability (in both [...]
Advancing forest aboveground biomass mapping by integrating GEDI with other Earth Observation data using a cloud computing platform: A case study of Alabama, United States
Published: 2024-04-06
Subjects: Applied Statistics, Climate, Earth Sciences, Environmental Monitoring, Environmental Sciences, Forest Management, Other Forestry and Forest Sciences
Forest aboveground biomass (AGB) is a crucial indicator for monitoring carbon and requires accurate quantification. This study aimed to advance AGB estimation using open access Earth observation (EO) data and cloud computing, focusing on Alabama, USA. The specific objectives were to: (1) develop a workflow for creating a 30 m forest AGBD map with GEDI, using GEE, (2) evaluate and compare [...]
Evaluation of the Sentinel-1 SAR image processing algorithms performance
Published: 2024-03-08
Subjects: Environmental Monitoring, Physical Sciences and Mathematics
The following paper discussed the performance of previously developed SAR algorithms applied to Sentinel-1 imagery. The outputs of algorithms were correlated to top-performing Sentinel-2 reNDVI algorithms. The study found that Levelled and Normalized Sigma nought outperformed the Gamma Nought, and, especially, Sigma Nought, and RVI algorithms.
Estimating irrigation water use from remotely sensed evapotranspiration data: Accuracy and uncertainties across spatial scales
Published: 2024-02-29
Subjects: Earth Sciences, Environmental Monitoring, Environmental Sciences, Hydrology, Sustainability, Water Resource Management
Irrigated agriculture is the dominant use of water globally, but most water withdrawals are not monitored or reported. As a result, it is largely unknown when, where, and how much water is used for irrigation. Here, we evaluated the ability of remotely sensed evapotranspiration (ET) data, integrated with other datasets, to calculate irrigation water withdrawals and applications in an [...]
Satellite-based surveys reveal substantial methane point-source emissions in major oil & gas basins of North America during 2022-2023
Published: 2024-02-28
Subjects: Atmospheric Sciences, Environmental Monitoring, Oil, Gas, and Energy, Remote Sensing
Utilizing imaging spectroscopy technology to identify methane super-emitters plays a vital role in mitigating methane emissions in the Oil & Gas (O&G) sector. While earlier research has uncovered significant point-source methane emissions from O&G production in the US and Canada, which are key regions with large methane emissions, a comprehensive post-COVID-19 survey has been notably [...]
A Mathematical Representation of Historical Greenhouse Gas Emissions with Rigorous Insights
Published: 2024-02-25
Subjects: Analysis, Environmental Monitoring, Longitudinal Data Analysis and Time Series, Numerical Analysis and Computation
In this paper, we analyze historical greenhouse gas (GHG) emissions worldwide, leveraging a dataset provided by (Gütschow and Pflüger, 2023). Employing mathematical modeling, a formal theory is developed, describing the growth trajectories of GHG emissions over time. The theory introduces several key concepts, including historical upper bound emission (HUBE), historical peak emission (HPE), and [...]
Multi-satellite data depicts record-breaking methane leak from a well blowout
Published: 2024-02-14
Subjects: Climate, Environmental Monitoring, Oil, Gas, and Energy
Accidental blowouts in oil and gas wells can result in large and prolonged methane emissions, which are often unreported when happening in remote places. The rapid advancement of space-based methods for detecting and quantifying methane plumes provides an essential tool for uncovering these super-emission events. We use a range of methane-sensitive satellites to document a methane leak from a [...]
Deployment-invariant probability of detection characterization for aerial LiDAR methane detection
Published: 2024-01-24
Subjects: Environmental Monitoring, Environmental Sciences
Accurate detection sensitivity characterization of remote methane monitoring technologies is critical for designing, implementing, and auditing effective emissions monitoring and mitigation programs. Several research groups have developed test methods based on single/double-blind controlled release protocols and regression-based data analysis techniques to create probability of detection (PoD) [...]
Model Ensemble with Dropout for Uncertainty Estimation in Binary Sea Ice or Water Segmentation using Sentinel-1 SAR
Published: 2024-01-20
Subjects: Applied Statistics, Environmental Monitoring, Signal Processing
Despite the growing use of deep learning in sea ice mapping with SAR imagery, the study of model uncertainty and segmentation results remains limited. Deep learning models often produce overconfident predictions, a concern in sea ice mapping where misclassification can impact marine navigation safety. We incorporate and compare dropout and model ensemble within a convolutional neural network [...]
Apportioning sources of chemicals of emerging concern along an urban river with inverse modelling
Published: 2024-01-18
Subjects: Environmental Monitoring, Environmental Sciences
Concentrations of chemicals in river water provide crucial information for assessing environmental exposure to fertilisers and insecticides, heavy metals, illicit drugs, pathogens, pharmaceuticals, plastics and perfluorinated substances among others. However, using concentrations measured along waterways to identify sources of contaminants and predict their fate is complicated by downstream [...]
Metrological approach for permafrost temperature measurements
Published: 2024-01-12
Subjects: Climate, Environmental Monitoring, Glaciology
Permafrost degradation is a growing direct impact of climate change. Detecting permafrost reductions, in terms of its extension, deepening of the active layer and rise of the base is fundamental to capture the magnitude of trends and address actions and warnings. Temperature profiles in permafrost allow direct understanding of the status of the frozen ground layer and its evolution in time. The [...]
Bayesian network modelling of phosphorus pollution in agricultural catchments with high-resolution data
Published: 2024-01-11
Subjects: Agriculture, Biochemistry, Environmental Monitoring, Statistical Models
A Bayesian Belief Network was developed to simulate phosphorus (P) loss in an Irish agricultural catchment. Septic tanks and farmyards were included to represent all P sources and assess their effect on model performance. Bayesian priors were defined using daily discharge and turbidity, high-resolution soil P data, expert opinion, and literature. Calibration was done against seven years of daily [...]
Open-source approach for reproducible substrate mapping using semantic segmentation on recreation-grade side scan sonar datasets
Published: 2023-12-21
Subjects: Analysis, Artificial Intelligence and Robotics, Databases and Information Systems, Environmental Monitoring, Hydrology, Natural Resources and Conservation, Numerical Analysis and Computation, Numerical Analysis and Scientific Computing, Programming Languages and Compilers, Software Engineering, Terrestrial and Aquatic Ecology, Water Resource Management
Knowledge of the variation and distribution of substrates at large spatial extents in aquatic systems, particularly rivers, is severely lacking, impeding species conservation and ecosystem restoration efforts. Air and space-borne remote sensing important for terrestrial and atmospheric measurements are limited in benthic environments due to river stage, turbidity, and canopy cover, requiring [...]
Untangling intercropping in heterogeneous smallholder maize-cassava farming systems with remote sensing
Published: 2023-12-15
Subjects: Environmental Monitoring, Environmental Sciences, Physical Sciences and Mathematics
Earth observation approaches for large-scale crop monocultures are often not transferable to heterogeneous smallholder systems. Key challenges in this regard are intercropping, high intra-field crop type variability, wide sowing windows, presence of non-crop vegetation and small but variable field sizes. Currently, studies on smallholder agriculture mainly focus on specific crops and seldom [...]