Downscaling CMIP6 Global Solutions to Regional Ocean Carbon Model: Connecting the Mississippi, Gulf of Mexico, and Global Ocean

Coupled physical-biogeochemical models can significantly reduce uncertainties in estimating the spatial and temporal patterns of the ocean carbon system. Challenges of applying a coupled physical-biogeochemical model in the regional ocean include the reasonable prescription of carbon model boundary conditions, lack of in situ observations, and the oversimplification of certain biogeochemical processes. In this study, we applied a coupled physical-biogeochemical model (Regional Ocean Modelling System, ROMS) to the Gulf of Mexico (GoM) and achieved an unprecedented 20-year high-resolution (5 km, 1/22°) hindcast covering the period of 2000–2019. The model’s biogeochemical cycle is driven by the Coupled Model Intercomparison Project 6-Community Earth System Model 2 products (CMIP6-CESM2) and incorporates the dynamics of dissolved organic carbon (DOC) pools as well as the formation and dissolution of carbonate minerals. Model outputs include generally interested carbon system variables, such as pCO2, pH, aragonite saturation state (ΩArag), calcite saturation state (ΩCalc), CO2 air-sea flux, carbon burial rate, etc. The model’s robustness is evaluated via extensive model-data comparison against buoy, remote sensing-based Machine Learning (ML) predictions, and ship-based measurements. Model results reveal that the GoM water has been experiencing an ~ 0.0016 yr−1 decrease in surface pH over the past two decades, accompanied by a ~ 1.66 µatm yr−1 increase in sea surface pCO2. The air-sea CO2 exchange estimation confirms that the river-dominated northern GoM is a substantial carbon sink. The open water of GoM, affected mainly by the thermal effect, is a carbon source during summer and a carbon sink for the rest of the year. Sensitivity experiments are conducted to evaluate the impacts from river inputs and the global ocean via model boundaries. Our results show that the coastal ocean carbon cycle is dominated by enormous carbon inputs from the Mississippi River and nutrient-stimulated biological activities, and the carbon system condition of the open ocean is primarily driven by inputs from the Caribbean Sea via Yucatan Channel.

Particle Simulation of The Strong Magnetic Field Effect On Dust Particle Charging Process

A particle-in-cell simulation is modeled and run on a dusty plasma to determine the effect of the magnetic field on the process dust-particle charging through electron-ion plasma. The electric field is solved through the Poisson equation, and the electron-neutral elastic scattering, excitation, and ionization processes are modeled through Monte Carlo collision method. The effects obderved from the initial density of the plasma, the initial temperature of the electrons, and the changing magnetic field are included in this simulation model. In the dust particle charging process, saturation time and saturation charge are compared. An increase in the magnetic field cannot reduce time to reach the saturation state. Determinig the magnetic field boundaries which depend on the physical properties of the plasma, which can be contributive in some areas of dusty(complex) plasma. The applications of the results obtaind here for fusion plasma conditions and space and laboratory plasmas are discussed. The results here can be applied in future simulation models with a focus on the dust particle movement and their effect on plasma, leading to the modeling of different astrophysical plasmas thorough laboratory experiments.

The Configuration of Supply Chain Concentration and Staff Structure in Intelligent Manufacturing: A Fuzzy Sets Qualitative Comparative Analysis

In traditional manufacturing enterprises, there are common problems of low added value of products, low profit, and poor business performance. As a result, they endeavor to transform themselves into intelligent manufacturing. To help with their transformation, this paper proposes a decision support model for managers to improve the business performance under different configurations of supply chain concentration and staff structure. Through the fuzzy set qualitative comparative analysis, the membership degree is given to the variables, and then the configuration analysis is carried out. We find that, to facilitate intelligent manufacturing, the concentration degree of supply chain or the structure of employee education should be adjusted according to the results from the qualitative comparative analysis of fuzzy sets. Two configuration paths to improve business performance are found. When the supply chain concentration degree is relatively decentralized, manufacturing enterprises should expand the proportion of sales personnel and production personnel. In other words, when the sales personnel and production personnel reach the saturation state, low concentration of suppliers and customers is more conducive to the improvement of business performance. The configuration of high proportion of production personnel and low customer concentration tends to lock enterprises in the lower end of the value chain. Therefore, it is critical for enterprises to improve the education level of employees to transform into intelligent manufacturing and improve their business performance.

KELEMBABAN UDARA DENGAN ALAT HUMYDIMETER PADA LAHAN SAWAH DI KELURAHAN TANAH MERAH

Humidity is the concentration of water vapor in the air. In agriculture, air humidity is associated with increased productivity and development of cultivated plants, humidity in the environment where it grows can determine the selection of appropriate plant species, the purpose of this study was to determine air humidity in paddy fields between April, May , and June, changes in air humidity at any time describe the water vapor content in the air can be expressed as absolute humidity, relative or vapor pressure deficit, relative humidity compares the actual water vapor content/pressure with its saturation state or the air's capacity to accommodate water vapor. The relationship between air humidity in paddy fields in Tanah Merah Village is relatively low, this is the impact of changes in temperature, quantity and quality of radiation, wind movement, air pressure, vegetation, and availability of water and productivity of irrigated ricefields

General 1-D hydrogeological model for temporal near-surface loess saturation assessment for the needs of radon potential mapping

Radon gas has high mobility and is driven by advection and diffusion with the soil gas throughout connected and water-unsaturated pores and/or cracks in permeable rocks and soils. Hence the radon potential of the area could be dependent on not only geology as a constant source of radon but also from the changes of the saturation state of the ground. The loess complex, characterized by its permeability and usual state of unsaturation, covers 10% of the Bulgarian territory. The study deals with the principles of unsaturated domain modeling. An attempt of generic vertical infiltration model coinciding with the most upper part of loess vadose zone was performed.

Crystallographic and chemical signatures in coral skeletal aragonite

Corals nucleate and grow aragonite crystals, organizing them into intricate skeletal structures that ultimately build the world’s coral reefs. Crystallography and chemistry have profound influence on the material properties of these skeletal building blocks, yet gaps remain in our knowledge about coral aragonite on the atomic scale. Across a broad diversity of shallow-water and deep-sea scleractinian corals from vastly different environments, coral aragonites are remarkably similar to one another, confirming that corals exert control on the carbonate chemistry of the calcifying space relative to the surrounding seawater. Nuances in coral aragonite structures relate most closely to trace element chemistry and aragonite saturation state, suggesting the primary controls on aragonite structure are ionic strength and trace element chemistry, with growth rate playing a secondary role. We also show how coral aragonites are crystallographically indistinguishable from synthetic abiogenic aragonite analogs precipitated from seawater under conditions mimicking coral calcifying fluid. In contrast, coral aragonites are distinct from geologically formed aragonites, a synthetic aragonite precipitated from a freshwater solution, and mollusk aragonites. Crystallographic signatures have future applications in understanding the material properties of coral aragonite and predicting the persistence of coral reefs in a rapidly changing ocean.

Salt Crust, Brine, and Marginal Groundwater of Great Salt Lake's North Arm (2019 To 2021)

Following the construction of the railroad causeway in 1959, a perennial halite (NaCl) bottom crust has been known to exist in the north arm (Gunnison Bay) of Great Salt Lake, Utah, but the lake conditions controlling accumulation or dissolution of the crust are not well defined, including how depth-controlled chemodynamic and hydrodynamic factors influence the degree of the halite saturation. Immediately prior to the opening of a new bridge in the causeway in early December 2016 when north arm lake elevation was at a historical low (just above 4189 feet), the north arm lake brine was at halite saturation. After the opening, inflow of less saline south arm water mixed with north arm water, raised lake elevation, and diluted the north arm lake brine to undersaturation with respect to halite. The following five years have resulted in annual and seasonal fluctuations of halite saturation states. Beginning in mid-2019, the Utah Geological Survey began a study of the north arm to better understand and document the transitions of halite saturation state following the bridge opening using newly collected data as well as reviewing available past data.

Constructing the Resistivity-to-Sediment-Type Transform for the Interpretation of Airborne EM Data

A novel Markov Chain Monte Carlo (MCMC) based methodology was developed for the transformation of resistivity, derived from airborne electromagnetic (AEM) data, into sediment type. This methodology was developed and tested using AEM data and well sediment type and resistivity logs from Butte and Glenn Counties in the Californian Central Valley. Our methodology accounts for the spatially varying sensitivity of the AEM method by constructing different transforms separated based on the sensitivity of the AEM method. The large spatial separation that typically exists between the AEM data and the wells with sediment type logs was avoided by planning the acquisition of AEM data so as to fly as close as possible to the well locations. We had 55 locations with sediment type logs and AEM data separated by 100 m, determined to be the maximum acceptable separation distance. Differences in vertical resolution between the AEM method and the sediment type logs were addressed by modeling the physics of the AEM measurement, allowing for a comparison of field and AEM data generated during the MCMC process. The influence of saturation state was captured by creating one set of transforms for the region above the top of the saturated zone and another for below. Using the set of transforms developed at the 55 locations, an inverse distance weighting scheme that included a well quality ranking was used to construct a set of 12 (six sensitivity bins, and two saturation states) resistivity-to-sediment-type transforms at every AEM data location. These represent a set of transforms that accommodate the variation in AEM sensitivity and are independent of the inversion used to retrieve the resistivity model. These transforms thus avoid two of the significant limitations common to resistivity-to-sediment-type transforms used to interpret AEM data.

The challenge in measuring low-permeability materials: a comparison of different approaches

The German repository site selection procedure calls for a radioactive waste containment zone with a low-permeability host rock (kf<10-10 m s−1, StandAG §23, 5) and long-term sealing by barrier materials (EndlSiAnfV, 2020; ESK, 2019). The potential host rocks, clay and rock salt, as well as the considered barrier materials, bentonite and compacted crushed salt, show permeability in the range of kf∼10-16 m s−1 (K∼10-21 m2). These low values suggest that advective flow is as slow as diffusive mass flux. Measuring such low permeability with adequate accuracy challenges measurement setups and respective error evaluation. Methodologies. Several low-permeability measurements are carried out by transient tests, e.g. by monitoring controlled fluid pressure changes in: (1) pressure decay and (2) oscillating pulse tests. The first method (1) deviates permeability from the time needed to compensate pressure differences through the sample. The latter (2) monitors phase shift and amplitude attenuation of controlled pressure pulses passing through the sample. Any permeability measurement needs to be post-processed, e.g. for: (1) material-intrinsic controls (saturation state, storativity, the fluids' compressibility, etc.), (2) environmental controls (temperature, confining pressures, etc.) and (3) theoretical considerations (Klinkenberg correction, multi-phase wetting angles, etc.). Salts. A porosity-permeability relation was found down to K=10-19 m2 (e.g., Popp et al., 2007). Testing fluids were NaCl brine, oils, He and N2 as a fluid. As a matter of current research, a critical, low-permeability value might be associated with the so-called “percolation threshold” that defines the minimal requirements for an interconnected pore system (e.g., DAEF, 2016). Clays. A major challenge is the long duration of sample saturation (up to several months) and pressure equilibration (often days), as well as precise, temperature-compensated measuring and the determination of the samples' storativity (e.g., Winhausen et al., 2021). Testing fluids are commonly designed mixtures mimicking the rocks' pore waters. Geotechnical barrier materials. The permeability testing performed is similar to that of salt and clays mentioned above. However, both barrier materials, crushed salt and bentonite, have significant permeability early after emplacement. This is beneficial, as it allows the outflow of unwanted canister corrosion gases. Eventually, the permeability drops by orders of magnitude and the barriers become tight seals in the long-term. Here, identifying the gas entry/breakthrough pressure has been valuable (e.g., Rothfuchs et al., 2007). Figure 1 shows a preliminary sensitivity analysis as an example of pressure decay measurements. It suggests that the pressure equilibration term (c), and hence the test duration, is most sensitive to the calculation of low permeability. However, the large variation of (representative) material and environmental controls make permeability measurements complex. This workshop aims to encourage discussions on uncertainty and sensitivity of the influencing controls, such that it may lead to a “best-practice” guide for permeability measurements.