Property:CSDMS meeting abstract
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The U.S. Geological Survey (USGS) is one of the largest providers of U.S. hydrologic data, which are used in informing policy, managing water resources, and countless scientific studies. Modern science is increasingly conducted by performing analysis on data that are first loaded from an online database into a local computational environment. To facilitate open and reproducible hydrologic science, the USGS has developed dataRetrieval (R), dataretrieval (Python), and DataRetrieval.jl (Julia): three packages providing multi-language access to hydrologic data from the U.S. Geological Survey, as well as the multi-agency Water Quality Portal. The Julia, Python, and R programming languages are open source, high-level (easy to program), have large communities of scientific users and developers. Notably, these three languages are the core languages supported by Project Jupyter, and run in the Jupyter Notebook, a popular web-based interactive computing platform.
These packages, collectively the “data retrievals,” allow scientists to programmatically access USGS hydrologic data in Julia, Python, and R. The “data retrievals” enable more than simply the retrieval of environmental data, they also provide tooling for data discovery, enabling users to find monitoring sites and identify what types of data are available at which locations. These functions represent foundational building blocks allowing for the creation of fully reproducible hydrologic workflows from data acquisition to output plots, tables, and reports. +
The U.S. Geological Survey is tasked with developing sustainable integrated hydrologic models that are interoperable with models from partner agencies and academia.
As a steppingstone towards integrating hydrologic models in a compiled code framework, we have developed a Python package for hydrologic process development and prototyping. This code base, named “pywatershed”, can seamlessly interact with our compiled code framework (MODFLOW 6) via its BMI interface. One can obtain numerically identical results from a model enhancement prototyped in Python or implemented in compiled code.
The advantages of code prototyped in Python are lower cost (person*hours) and greater approachability (less specialized programming knowledge required). The drawback of prototype code is that it may be slower to run for certain applications. A prototyping approach supports proof-of-concept development and model hypothesis testing, particularly for domain experts who may be more comfortable in Python and who bring new approaches or novel data to integrated model applications. The prototyping approach supports a cost-benefit analysis for making decisions to implement certain hydrologic process representations within the compiled code base.
The current state of this evolving Python package will be described, including: 1) the modular, self-describing design based on control volumes and conservation of mass and energy, 2) numerical performance based on the numpy Python package, the numba Python package (just in time compiling), and compiled Fortran modules called from python, 3) goals and challenges of developing flexibility in the space and time representation of hydrologic processes and the management of fluxes and states between process representations, and 4) the current and upcoming set of hydrologic process representations.
Example notebooks will demonstrate many features of pywatershed. Planned developments will be described and community participation is welcomed.
The US east coast is heavily developed, necessitating adaptive approaches to mitigate property and infrastructure risk from storm events and shoreline changes. One soft-structural approach, beach nourishment, comprises artificial shoreline progradation for property protection. Construction of groins, a hard-structural approach, traps alongshore transported sediments, leading to updrift shoreline growth. Groins create a depositional sediment shadow in their lee, shrinking downdrift shorelines, thereby forcing communities to decide whether to protect properties or to retreat. Our research focuses on how these alternative adaptations may affect coastal risk. We present two field scenarios: West Hampton Dunes, NY, which decided to protect downdrift property through beach nourishment, and Oakwood Beach, NY, which decided to accept buyout offers from federal disaster relief funds. We build a coupled geo-economic model to explore management drivers and controls on coastal morphology and real estate and to analyze the emergent indicators within a two-community system. We quantify benefits as a function of beach width, number of housing rows, and federal property buyouts; costs are a function of groin construction, groin maintenance, and beach nourishment. We compare the net benefits of downdrift nourishment, retreat, and groin removal for different groin lengths, background erosion rates, baseline property values, and discount rates. Results elucidate which approach is most beneficial for coastal adaptation, providing a simple framework to compare future strategies for West Hampton Dunes. This geo-economic tool may prove useful as lawmakers continue to scrutinize fiscal implications of alternative adaptations to coastal risks. +
The USGS Model Catalog compiles and connects data, software, and publications about scientific models developed by the U.S. Geological Survey (USGS) or developed by external organizations and used in USGS investigations. The primary audience for the USGS Model Catalog is researchers who want to learn more about USGS modeling, such as researchers who want to explore existing models and documentation on a specific topic; early career researchers who want to see what models exist in their discipline; or members of large, integrative projects who want to discover opportunities for linking different process models. The catalog is composed of modular features that we hope other projects can build upon. The data model and repository component are published at https://doi.org/10.5066/P9WU0F71 and https://doi.org/10.5066/P9IVG9VZ.
The catalog is never complete! Come take a look at what's there now, learn what we're planning, and give input about what content and features would help you and your communities. Visit the catalog at https://data.usgs.gov/modelcatalog. +
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The Underworld code was designed for solving (very) long timescale geological deformations accurately, tracking deformation and evolving interfaces to very high strains. It uses a particle-in-cell based finite element method to track the material history accurately and highly-tuned multigrid solvers for fast implicit solution of the equations of motion. The implementation has been fully parallel since the inception of the project, and a plugin/component architecture ensures that extensions can be built without significant exposure to the underlying technicalities of the parallel implementation. We also paid considerable attention to model reproducibility and archiving — each run defines its entire input state and the repository state automatically.
A typical geological problems for which the code was designed is the deformation of the crust and lithospheric mantle by regional plate motions — these result in the formation of localised structures (e.g. faults), basins, folds and in the generation of surface topography. The role of surface processes — redistributing surface loads and changing boundary conditions, is known to be significant in modifying the response of the lithosphere to the plate-derived forces. The coupling of surface process codes to Underworld is feasible, but raises some interesting challenges (and opportunities !) such as the need to track horizontal deformations and match changes to the topography at different resolutions in each model. We will share some of our insights into this problem. +
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The WBMsed model offers a unique framework for studying river flux dynamics, ranging from basin to global scales. When it was first published in 2013, WBMsed included a spatially and temporally explicit suspended sediment flux module, developed within the WBMplus (FrAMES) hydrological framework. Since then the model has been used for a range of studies and been extended to include a bedload, water density, and particulete nutrients modules. The model's hydrological and geomorphic processes were improved to better represent riverine and landscape dynamics. These include the introduction of a flooding mechanism, spatially-explicit river slope, and land use inputs. Here we will outline these model development and its use for river and coastal studies. +
The Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro) is an open-source community model and has been used for a range of projects, including flash flood prediction, regional hydroclimate impacts assessment, seasonal forecasting of water resources, and land-atmosphere coupling studies. We modified the CASCade 2 Dimensional SEDiment (CASC2D-SED) model and adapted it to the WRF-Hydro platform. The model mainly contains two components: (1) sediment erosion and transport from overland to channel, and (2) sediment transport through the channel to the watershed outlet. Based on USLE formula, sediment is eroded by overland flow with consideration of soil type, vegetation type as well as bed slope. Following through the direction of steepest slope, the eroded sediment is transported grid by grid all the way to the channel, meanwhile deposition process is parameterized by sediment’s settling velocity, time step and water depth. Once sediment gets into channel, it will be carried by the stream flow to the watershed outlet. To test its robustness, we adapted WRF-Hydro sediment model to the watershed of Goodwin Creek, Mississippi, USA. A preliminary model-data comparison indicates our model is capable of reproduce water and sediment discharge during a storm event. +
The Whitewater River in southeastern Minnesota is one of numerous tributaries of the upper Mississippi River. However, unlike many of the tributaries to the Mississippi north of the Whitewater River, which received glacially derived sediment and water directly from the Laurentide Ice Sheet margin, the Whitewater watershed remained ice free. Instead, glacial–interglacial cycling predominately shaped the watershed via changes in base-level and sediment inputs on the mainstem Mississippi. Thus, the aggradation and incision of the mainstem upper Mississippi acted as the primary source of glacial signal in the watershed. In this study, we seek to understand how the complex glacial history of the upper Mississippi River impacted the long-profile evolution of the Whitewater River. To do this, we combine one-meter LiDAR topography with the topographic analysis package, LSDTopoTools to study the modern channel network and adjacent terraces. By extracting modern and historic river terraces, we are able to reconstruct channel long-profile changes over time. We pair this study with bedrock geology composition and depth to bedrock for the watershed to understand transitions within the watershed from transport to detachment limited and linkages between bedrock type and channel morphology. This work allows us to better constrain how glacial–interglacial signals propagate through fluvial systems via tributaries. This information can better inform our understanding of how tributaries respond to mainstem changes and how these changes propagate over time. +
The accumulated history of crater production and destruction is recorded in crater size-frequency distributions (CSFDs), which can be leveraged to understand the evolution of planetary surfaces and atmospheres. For example, researchers used the size-frequency distribution of craters interbedded with fluvial deposits to provide an upper-bound of ~1.9 bar on paleo-atmospheric pressure at the time of river activity on Mars. Interpretations of paleo-atmospheric pressure are most sensitive to preservation and mapping of smaller craters (<50 m), which may be influenced by fluvial reworking. We simulated river-delta development with coeval crater production; river-delta simulation is completed with pyDeltaRCM and craters 10 to 300 m are generated according to an imposed crater production function and placed randomly and with a parameterized geometry. We quantified preservation of craters in the stratigraphy after 1, 10, or 100 Ma of coupled landscape evolution. Our results indicate that crater preservation is highly variable (ranging fully eroded to fully preserved), but preserved fraction generally increases with crater diameter. Despite rivers removing a substantial portion of smaller craters (>40% of craters <50 m are at least partially eroded); exponential increase in crater counts with decreasing size overwhelms any meaningful fluvial preservation bias. Our findings bolster previous studies that assert fluvial reworking is a secondary controls to atmospheric ablation on CSFDs, indicating that paleo-atmospheric pressure upper-bounds may be translated into estimates (with uncertainty). +
The accuracy of sediment transport models depends heavily on the selection of an appropriate sediment settling velocity. Determining this value for mud suspensions can be difficult because the cohesive particles within the mud can aggregate to form flocs whose sizes are a function of hydrodynamic and physiochemical conditions of the suspension. Here we present a new model for predicting floc size in a dynamic way as a function of the hydrodynamic conditions and inherited floc sizes. The new model is a simple modification to the existing Winterwerp (1998) floc size model. The modification is significant in that it yields predictions that are more inline with observations and theory regarding the upper limit on ultimate floc size. The modification we propose is to make the ratio of the applied stress on a floc over the strength of the floc a function of the floc size relative to the Kolmogorov microscale. The outcome of this modification is that flocs are not allowed to surpass the Kolmogorov microscale in size and that calibrated aggregation and breakup coefficients obtained at one suspended sediment concentration can be used to predict floc size under other concentration values without recalibration of the coefficients. In this paper, we present the motivation for the modification, the functionality of the modification, and a comparison of the updated model with laboratory and field data. Overall the model shows promise as a tool that could be incorporated into larger hydrodynamic and sediment transport models for improved prediction of cohesive mud transport. +
The active volcano Ol Doinyo Lengai is located in the magma-rich southern Eastern Branch of the East African Rift and erupts unique low-temperature carbonatites. Between 2007 and 2010, the volcano had several explosions and erupted with ash falls, and lava flows (VEI 3) that caused damage to the nearby communities. Although this volcano has been studied for decades, its plumbing system is still poorly understood, in part, because of the lack of precise observations of surface deformation during periods of quiet and unrest. This study investigates the volcanic plumbing system of Ol Doinyo Lengai and surroundings using data from the permanent Global Navigation Satellite System (GNSS) network monitoring the volcano called TZVOLCANO and Interferometric Synthetic Aperture Radar (InSAR) observations. We calculate velocities for 6 continuously operating GNSS sites distributed around Ol Doinyo Lengai for a timespan between 2016 and 2021 and also process InSAR data for nearly the same time-period to constrain surface motions. We then use the GNSS deformation signals and InSAR observations to solve for magma sources embedded in a homogeneous and elastic half space using the USGS inversion code dMODELS. Both GNSS and InSAR inversion results quantify a deflating spherical geometry source at a depth of ~1.3 km with a volume change ∆V of -0.05 ± 0.01x106m3 located east of Ol Doinyo Lengai and southwest of the dormant volcano Gelai. InSAR inversions alone also suggest a closing dike model at a depth of ~9 km similar to the location resolved for the 2007 Ol Doinyo Lengai dike. This work suggests a shallow magma reservoir exists east of Ol Doinyo Lengai and that the 2007 dike is actively contracting. This magma source influences the onset, size, duration and hazard of eruptions of the volcano, and plays a significant role in triggering slip on border faults during early phases of continental rifting through stress transfer. +
The characteristics of soils control the influence of how land use and land cover (LULC) change the global water, energy, and biogeochemical cycles. Plant health, and the exchange of energy, water and biogeochemical components at the surface interface is partly controlled by soil properties. Different soil types modify vegetation responses to existing climate forcings, and each soil type also responds differently to the same land-use practice. Currently, Earth System Models often use single soil columns with averaged properties and the same properties stay constant over time regardless of LULC changes. This leads to uncertainties in assessing LULC impacts. To improve the estimates of land surface change in Earth System Models, we build a soil degradation model to compute annual soil properties from 850 to 2015.
The model includes three parts: first, to quantify human LULC impacts, we collected 1099 observations from 174 published literature of human impacts of agriculture, pasture, grazing, and vegetation harvest on soil organic carbon (SOC), texture, and bulk density. Under each LULC unit, we defined the combined impact of LULC, management, climate (represented by NPP or moisture index), and soil texture on each soil property based on observations and regression models. In the second part, we link an existing LULC dataset to four hydrologic soil groups from 850 to 2015, based on demonstrated soil preferences for eight LULCs under current conditions. We conclude that humans prefer hydrologic soil groups (HSGs) in order from B, D, C, to A (generally from high to low silt content). This ranking was applied to construct the history of LULC on each soil type at the half-degree grid resolution. Results primarily distribute croplands to HSG B in 850, while HSG A has the most undisturbed area. Over time, preferred soils (HSGs B and D) experience increased use for cropland areas, while poor soils (HSGs C and A) are occupied predominantly by increasing areas in grazing land and secondary non-forests. Finally, based on the established LULC and soil relations from 850 to 2015, we altered soil properties in each soil group according to global variations of environmental factors to model human-induced soil degradation. Vertical and temporal variations are applied based on observations. Results demonstrate how soil degradation occurs under historical LULCs and provide better land surface characteristics to improve Earth systems modeling.
The coastline of SE Alaska was submerged by post-Pleistocene sea level rise from at least 16,000 cal yrs BP until it stabilized about 10,600 cal yrs BP. The submerged continental shelf was modeled using bathymetry and other data to identify areas exhibiting high potential for the occurrence of archaeological sites. Two seasons of underwater archaeological survey have been conducted at this location (NSF OPP -#0703980 and 1108367), using multibeam sonar, side-scan sonar, sub-bottom profiler, real-time video from remotely operated vehicle (ROV), and sea floor sampling using a van veen grab sampler and sediment screening. This data has produced a detailed overview of Shakan Bay, located on the northwest corner of Prince of Wales Island. +
The controls exerted on stream channel form by rock properties contribute to landscape morphology. Here we focus on understanding the effects of bedrock properties on surface processes and landscape evolution in the Guadalupe Mountains of South Eastern New Mexico. We surveyed bedrock reaches in three different watersheds, taking rock samples, Schmidt hammer measurements, and videos of reaches. We used structure for motion to generate orthomosaics of surveyed reaches from the video. We then traced fractures and determined fracture intensity, average length of fractures per square meter, for each reach. XRD data taken from samples collected in the field, along with carbonate dissolution techniques, demonstrates the minerology of reaches. In relatively small watersheds there is little climate variation which is demonstrated using PRISM climate data. Lithologic variance and channel steepness are the main control on differences in rock properties within stream channels. Steeper channels cut across more bedding planes than shallow reaches, influencing both fracture intensity and Schmidt hammer values. At the landscape scale rock strength is reflective of differential weathering due to differences in climate for similar rock types. Results from this study will help to reconcile our understanding of the effect of climate and lithology on surface processes at different scales. It will also create a widely applicable methodology for measuring, interpreting, and comparing various metrics of rock properties. +
The detachment of intact blocks of substrate material from channel surfaces by flow hydraulics (“plucking”) is a key mechanism driving erosion in both natural and man-made channels. Despite its role in knickpoint migration and channel boundary adjustment, the physical processes controlling block motion remain poorly constrained. In particular, we lack measurements of the instantaneous turbulent pressure field and its interaction with block geometry and fracture networks at the onset of motion. Turbulent fluctuations contribute to the forces acting on objects exposed to flows and may act to initiate motion even when bulk flow metrics remain steady. This project directly measures turbulent pressure fluctuations acting on a simulated bedrock block at a downstream-facing step in subcritical, critical, and supercritical flows to quantify the forces contributing to fluvial plucking. Laboratory flume experiments employ a “bedrock” cube instrumented with 66 pressure transducers and two accelerometers, enabling simultaneous measurement of instantaneous pressures and block motion. Block protrusion (−20 to +20 mm) and fracture (joint) width (0–100 mm) are systematically varied to quantify their effects on the lift and drag forces and the sequence of block motion, including initial lift, rotation, and translation. I use planar particle image velocimetry (PIV) to resolve the near-bed velocity field and shear stress acting on the block top. The resulting dataset will provide new mechanistic insights into how flow turbulence and fracture geometry control block entrainment which may be applied to existing erosional frameworks and models of bedrock plucking such as the Hurst 1D erosion (H1DE) model. +
The development of bedrock steps and waterfalls in mountain rivers locally changes flow hydraulics and can thereby alter patterns of sediment transport and erosion. While bedrock steps are thought to erode sometimes faster and sometimes slower than river reaches eroding without steps, it is unclear how differences in step frequency and morphology (e.g., the presence of many small bedrock steps and waterfalls versus the presence of a single large waterfall) alter channel dynamics and erosion rates at the reach scale. Furthermore, we do not know whether some or all step-rich channels are part of a transient knickzone or could be formed at steady state. Here, we use cosmogenic beryllium-10 (Be-10) erosion rates to examine whether bedrock steps alter the reach-averaged erosion rate. We find that all step-rich channels erode faster than or equal to catchment-average rates and preliminary analyses show that reach-scale erosion rates increase with increasing sediment flux, increasing grain size, and increasing step frequency. We compare our field results with a reach-scale erosion model we developed that combines both fluvial erosion at bedrock steps and fluvial erosion in reaches lacking steps. Our new reach-scale erosion model allows us to infer changes in erosion rates as a function of step frequency and step and channel morphology (e.g. dimensions of steps, and width and slope of channel between steps). This model will help interpret the impact of bedrock steps on erosion rates and determine their role in either adjusting or maintaining river profiles. +
The development of colluvial wedges at the base of fault scarps following normal-faulting earthquakes serves as a sedimentary record of paleoearthquakes and is thus crucial in assessing seismic hazard. Although there is a large body of observations of colluvial wedge development, connecting this knowledge to the physics of sediment transport can open new frontiers in our understanding. Here, I present a cellular automata model of fault scarp and colluvial wedge evolution built using CelllabCTS and the GrainHill sediment physics from Landlab. The model appears to accurately reflect the development of real fault scarps. When one analyzes the model results, one may note interesting groupings of cells with similar sediment transport histories as the fault scarp evolves. These groupings appear to match real world sedimentological facies, such as 'debris' and 'wash' facies, which brings up an interesting question of how best one can compare model results with geological data. I discuss some approaches and quandaries and how one may go about about translating modeling concepts and language into field concepts and language and vice versa. +
The efficiency of fluvial sediment and particulate organic carbon (POC) burial in river deltas strongly depends on their depositional environment, which can range from protected incised valleys to exposed active margins. Here, we hypothesize that the formation and infilling of incised valleys from Holocene sea-level rise led to increases in fluvial sediment burial efficiency, and, consequently, POC burial. To test this, we developed a new incised valley fill model that estimates incised valley volume and fill rates. We apply this model to all river deltas globally (n~11,000), some of which are filled already but many are still infilling since Holocene sea-level rise slowed ~6ka BP. The rate of incised valley infilling is determined based on global model estimates of fluvial sediment and POC supply. We use our model to explore the magnitude of POC burial during the Holocene, including its potential for global climate regulation. +
The escalating rate of forest mortality, fueled by increasing climate variability and the spread of exotic pests and diseases, is a growing global concern. A significant contributor to this issue in North America is the Emerald Ash Borer (EAB), an invasive pest responsible for the widespread destruction of ash trees (Fraxinus spp.), resulting in a sharp increase in the number of snags. Snags, or dead-standing trees, present significant risks to infrastructure, including buildings and electrical distribution systems. Our study focuses on New Jersey, a highly urbanized state with an extensive electric grid that intersects forested areas, many of which are populated with Fraxinus trees. In this research, an annual risk assessment methodology for evaluating the threat that Fraxinus snags pose to the electrical distribution infrastructure is presented, particularly in the context of New Jersey's ongoing efforts to enhance the resiliency and capacity of its electric distribution network through capacity upgrades. Employing an integrated approach composed of GIS, differential equations, and applied regression modeling, our analysis spans three northern New Jersey counties: Warren, Sussex, and Morris. These counties, which are under the utility management of New Jersey Central Power and Light, harbor a significant portion of the state's Fraxinus population, making them crucial areas for assessing the impact of snags on the electrical distribution infrastructure under different network parameterizations. +
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The evolution of fluvial deltas involves a complex web of processes, many of which are yet poorly understood. In particular, the role of organic matter (peat) accumulation on delta dynamics still remains elusive. Here, we present a simple geometric prism model that couples the evolution of the delta plain with the accumulation of organic-rich sediment. The model is able to explain the observed coupling between the accommodation/peat accumulation ratio and the quality of buried peat/coal deposits in the delta plain. Similarly to multiple modern and ancient organic-rich sedimentary environments, the model preserves the maximum volume fraction of organic sediment in the delta plain when the overall accommodation rate approximately equals the rate of peat accumulation. Further analysis of the model under simple scenarios of base-level rise and pivot subsidence shows that organic matter accumulation can either enhance or alleviate shoreline transgression. +
