High-resolution wind speed measurements with quadcopter uncrewed aerial systems: calibration and verification in a wind tunnel with an active grid
Johannes Kistner, Lars Neuhaus, and Norman Wildmann
Atmos. Meas. Tech., 17, 4941–4955, https://doi.org/10.5194/amt-17-4941-2024, 2024
We use a fleet of multicopter drones to measure wind. To improve the accuracy of this wind measurement and to evaluate this improvement, we conducted experiments with the drones in a wind tunnel under various conditions. This wind tunnel can generate different kinds and intensities of wind. Here we measured with the drones and with other sensors as a reference and compared the results. We were able to improve our wind measurement and show how accurately it works in different situations.
Retrieving cloud base height and geometric thickness using the oxygen A-band channel of GCOM-C/SGLI
Takashi M. Nagao, Kentaroh Suzuki, and Makoto Kuji
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-141,2024
Preprint under review for AMT (discussion: open, 0 comments)
In satellite remote sensing, estimating cloud base height (CBH) is more challenging than estimating cloud top height because the cloud base is obscured by the cloud itself. We developed an algorithm using the specific channel (known as the oxygen A-band channel) of the SGLI instrument on JAXA’s GCOM-C satellite to estimate CBH together with other cloud properties. This algorithm can provide global distributions of CBH across various cloud types, including liquid, ice, and mixed-phase clouds.
Deep-learning-driven simulations of boundary layer clouds over the Southern Great Plains
Tianning Su and Yunyan Zhang
Geosci. Model Dev., 17, 6319–6336, https://doi.org/10.5194/gmd-17-6319-2024, 2024
Using 2 decades of field observations over the Southern Great Plains, this study developed a deep-learning model to simulate the complex dynamics of boundary layer clouds. The deep-learning model can serve as the cloud parameterization within reanalysis frameworks, offering insights into improving the simulation of low clouds. By quantifying biases due to various meteorological factors and parameterizations, this deep-learning-driven approach helps bridge the observation–modeling divide.
Mixed-precision computing in the GRIST dynamical core for weather and climate modelling
Siyuan Chen, Yi Zhang, Yiming Wang, Zhuang Liu, Xiaohan Li, and Wei Xue
Geosci. Model Dev., 17, 6301–6318, https://doi.org/10.5194/gmd-17-6301-2024, 2024
This study explores strategies and techniques for implementing mixed-precision code optimization within an atmosphere model dynamical core. The coded equation terms in the governing equations that are sensitive (or insensitive) to the precision level have been identified. The performance of mixed-precision computing in weather and climate simulations was analyzed.
GREAT v1.0: Global Real-time Early Assessment of Tsunamis
Usama Kadri, Ali Abdolali, and Maxim Filimonov
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-139,2024
Preprint under review for GMD (discussion: open, 0 comments)
The GREAT v1.0 software introduces a novel tsunami warning technology for global real-time analysis. It leverages acoustic signals generated by tsunamis, which propagate faster than the tsunami itself, enabling real-time detection and assessment. Integrating various models, the software provides reliable and rapid assessment, mapping risk areas, and estimating tsunami amplitude. This advancement reduces false alarms and enhances global tsunami warning systems' accuracy and efficiency.
Alquimia v1.0: A generic interface to biogeochemical codes – A tool for interoperable development, prototyping and benchmarking for multiphysics simulators
Sergi Molins, Benjamin Andre, Jeffrey Johnson, Glenn Hammond, Benjamin Sulman, Konstantin Lipnikov, Marcus Day, James Beisman, Daniil Svyatsky, Hang Deng, Peter Lichtner, Carl Steefel, and David Moulton
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-108,2024
Preprint under review for GMD (discussion: open, 0 comments)
Developing scientific software and making sure it functions properly requires a significant effort. As we advance our understanding of natural systems, however, there is the need to develop yet more complex models and codes. In this work, we present a piece of software that facilitates this work, specifically with regard to reactive processes. Existing tried-and-true codes are made available via this new interface, freeing up resources to focus on the new aspects of the problems at hand.
Abstract
Ozone-depleting substances (ODSs) are well known as primary emission from the production and consumption of traditional industrial sectors. Here, we reported the unintentional emission of ODSs from iron and steel plants as a new source, basing on real-world measurements of flue gases emitted from their major processes. The sintering was found to be the major emission process of ODSs, including chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), halons, methyl halide (CH3Cl), methyl chloroform, carbon tetrachloride, methyl bromide and halogenated very short-lived substances. The median emission factors of CFC-113, CFC-115, HCFC-22, and CH3Cl for typical sintering processes are 1.7, 0.7, 44.5 and 237.0 mg/t, respectively. Quantum chemical calculation figures out that the ODS species are mainly formed in the low efficiency combustion process of halogenated materials. Annual amounts of ODS and CFC-11-equivalent emissions were estimated to be 1,785 tons and 78 tons in 2019 over mainland China, respectively. Given these findings, this study provides a new prospective on searching for ODS emission sources, especially unintentional sources such as iron and steel industry and other combustion related activities.
Abstract
The inverse temperature layer (ITL) beneath water-atmosphere interface within which temperature increases with depth has been observed from measurement of water temperature profile at an inland lake. Strong solar radiation combined with moderate wind-driven near-surface turbulence leads to the formation of a pronounced diurnal cycle of the ITL predicted by a physical heat transfer model. The ITL only forms during daytime when solar radiation intensity exceeds a threshold while consistently occurs during nighttime. The largest depth of the ITL is comparable to the e-fold penetration depth of solar radiation during daytime and at least one order of magnitude deeper during nighttime. The dynamics of the ITL depth variation simulated by a physical model forced by observed water surface solar radiation and temperature is confirmed by the observed water temperature profile in the lake.
Abstract
Mafic magma recharge of crustal reservoirs and subsequent magma mixing has been considered a direct trigger of volcanic eruptions. However, although recharge frequently occurs in many active volcanoes, it rarely leads to an eruption immediately, making its role as a trigger ambiguous. Sakurajima volcano, Japan, has vigorously erupted three times since the 15th century following a common process; mixed magmas after recharge were once stored in a shallow, thick conduit before each eruption (conduit pre-charge). We reconstructed the magma migration with a high time resolution by diffusion modeling on orthopyroxene and magnetite. Orthopyroxene phenocrysts recorded prolonged diffusive re-equilibration timescales of years or more after recharge-and-mixing. Magnetite, which has the fastest elemental diffusivity among the phenocrysts examined, predominantly lacks zoning. This demonstrates that the mineral phase was re-equilibrated with surrounding magma and homogenized via elemental diffusion after the final magmatic perturbation, implying the final repose of the shallow pre-charged magma body for more than several tens of days. After this shallow stagnation period, the Plinian magmas began to ascend and reached the surface within 55 hr. Mass balance calculations show that crystallization-driven vesiculation upon pre-charge can produce overpressure sufficient to cause an eruption. The Sakurajima cases demonstrate the hierarchical timescales of trigger processes leading to the explosive eruptions.
Abstract
Simulating dynamic rupture of fault systems can be computationally demanding, as it requires reproducing complex fault geometry and accurately capturing waves propagating away from the rupture front. It is in particular challenging to predict an initial stress state consistent with fault geometries, heterogeneous distribution of surrounding materials, and far-field tectonic loading. While standard techniques such as contact analysis and Lagrangian multipliers can be used to model the fault, it can lead to significant computational overhead in FEM. We extended Particle Discretization Scheme-FEM, which provides numerically efficient crack treatment, without requiring contact analysis, to simulate dynamic fault rupture as a frictional crack propagating along a pre-existing shear crack surface. Initial stress, which is consistent with initial frictional forces, material distribution and fault geometry, is derived using Coulomb friction and far-field boundary conditions. The study first demonstrates the ability of the numerical method to reproduce a 2D ideal supershear scenario, and the underlying Burridge-Andrew rupture mechanism. The methodology is then applied to the large scale simulation of the 2018 Palu earthquake on the Palu-Koro fault. The simulation successfully reproduces the early and sustained supershear rupture which was observed for the Palu earthquake. Also, it indicates that the presence of an off-fault damage zone can contribute to the low rupture velocity measured during the earthquake. Unlike sub-Rayleigh earthquakes, the shockwave propagation was observed to lead to significant amplitudes of the ground motion even far from the fault.
No abstract is available for this article.
Comparison of Inductive and Capacitive End Couplings in the Design of a Combline Microwave Cavity Filter for the E1 Galileo Band
Enrico Boni, Giacomo Giannetti, Stefano Maddio, and Giuseppe Pelosi
Adv. Radio Sci., 22, 1–8, https://doi.org/10.5194/ars-22-1-2024, 2024
The manuscript is about the design and experimental characterization of microwave filters to be used for satellite communication, especially for the E1 Galileo band. To feed the filter with microwave power, inductive and capacitive coupling schemes are adopted and compared. The measurement results show a good agreement with simulated ones. The outcome of this research is to compare the inductive and capacitive coupling schemes in the design of combline cavity filters.
Abstract
The sensitivity of tree growth to precipitation regulates their responses to drought, and is a crucial metric for predicting ecosystem dynamics and vulnerability. Sensitivity may be changing with continuing climate change, yet a comprehensive assessment of its change is still lacking. We utilized tree ring measurements from 3,044 sites, climate data and CO2 concentrations obtained from monitoring stations, combined with dynamic global vegetation models to investigate spatiotemporal changes in the sensitivity over the past century. We observed an increasing sensitivity since around 1950. This increased sensitivity was particularly pronounced in arid biomes due to the combined effect of increased precipitation and elevated CO2. While elevated CO2 reduced the sensitivity of the humid regions, the intensified water pressure caused by decreased precipitation still increased the sensitivity. Our findings suggest an escalating vulnerability of tree growth to precipitation change, which may increase the risk of tree mortality under future intensified drought.
Abstract
Negative Air Ions (NAIs), essential for environmental and human health, facilitate air purification and offer antimicrobial benefits. Our study achieves hourly estimations of NAIs using a machine learning framework, developed from a multi-layer selection pipeline of over 200 variables, to identify the key determinants critical for adapting to high-resolution NAIs dynamics. Addressing site sparsity and NAIs volatility, we introduced a hybrid stacking incorporating pseudo sites generated from Kriging Spatiotemporal Augmentation (KSTA) to mitigate spatial overfitting. Our approach, validated in Zhejiang, China, demonstrates exceptional accuracy, achieving R
2 values of 0.90 (sample-based), 0.85 (temporal-based), and 0.79 (site-based). This work not only sheds light on NAIs behavior in relation to diurnal shifts, land use, and environmental events, but also integrates a health grading system, enhancing public health strategies through precise air quality assessment.
Abstract
In recent years, it has been found that magnetic dip caused by diamagnetic motion of injected plasma can provide an appropriate environment for excitation of electromagnetic ion cyclotron (EMIC) waves. These findings have been widely reported in the Earth's magnetic environment. However, it has rarely been reported in Jupiter's magnetic environment. This paper reports the characteristics of EMIC waves observed by Juno in the magnetic dip of Jupiter. Multiple-band EMIC waves are observed in frequency range from 10−3 Hz to several Hz. The theoretical analysis shows that in this event both He+ band and O+ band EMIC waves can be constrained in the magnetic dip, which is consistent with the wave emissions observed inside the magnetic dip. Our result provides the first evidence that EMIC wave can be ducted inside a magnetic dip in Jupiter's magnetosphere.
Abstract
On 18 November 2023, SpaceX launched the Starship, the tallest and the most powerful rocket ever built. The Super Heavy engine separated from the Starship spacecraft and exploded at 90 km of altitude, while the main core Starship continued to rise up to 149 km and exploded after ∼8 min of flight. In this work, we used data from ground-based GNSS receivers and we analyzed total electron content (TEC) response to the Starship flight and the two explosions. For the first time, we observed large-distance northward propagation of intensive 2,000 km V-shaped ionospheric disturbances from the rocket trajectory. The observed perturbations, most likely, represent shock waves propagating with the cone angle of ∼14° on the North and ∼7° on the South against the flight track that corresponds to the Mach angle of the shock waves in the lower atmosphere. The Starship explosion also produced a non-chemical depletion in the ionospheric TEC.
Abstract
The Arctic rapidly warms and sea ice retreats, a large fraction of organic carbon (OC), currently stored in coastal permafrost will be released into the marine system. Once reintroduced into the active carbon cycle, this material will either be decomposed or buried on the shelf depending on its hydrodynamic and chemical properties. Currently, carbon estimates are based on bulk measurements, which does not take the hydrodynamic pathway of different fractions into account. Therefore, eight coastal permafrost locations have been sampled along the Canadian Beaufort Sea Coast, hydrodynamically fractionated and analyzed for their C, N, 13C and 14C content. We found that the matrix-free fraction (low density <1.8 g/cm3, and high-density >1.8 g/cm3; <38 μm) account for 77%–98% of the OC. By using a coastal classification combined with field data, our results showed that short coastal segments can become key players in delivering matrix-free, easily degradable OC to the marine system.
High-altitude balloon-launched uncrewed aircraft system measurements of atmospheric turbulence and qualitative comparison with infrasound microphone response
Anisa N. Haghighi, Ryan D. Nolin, Gary D. Pundsack, Nick Craine, Aliaksei Stratsilatau, and Sean C. C. Bailey
Atmos. Meas. Tech., 17, 4863–4889, https://doi.org/10.5194/amt-17-4863-2024, 2024
This work summarizes measurements conducted in June 2021 using a small, uncrewed, stratospheric glider that was launched from a weather balloon to altitudes up to 30 km above sea level. The aircraft conducted measurements of wind speed and direction, pressure, temperature, and humidity during its descent as well as measurements of infrasonic sound levels. These data were used to evaluate the atmospheric turbulence observed during the descent phase of the flight.
Estimating hourly ground-level aerosols using GEMS aerosol optical depth: A machine learning approach
Sungmin O, Ji Won Yoon, and Seon Ki Park
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-142,2024
Preprint under review for AMT (discussion: open, 0 comments)
Air pollutants such as PM10 or PM2.5 can cause adverse public health and environment effects, therefore their regular monitoring is crucial to keep the pollutant concentrations under control. Our study demonstrates the potential of high-resolution aerosol optical depth (AOD) data from the Geostationary Environment Monitoring Spectrometer (GEMS) satellite to estimate ground-level PM concentrations using a machine learning model.
Abstract
Precipitation δ18O has offered valuable insights into the evolution of the Asian monsoon. Recent researches focusing on precipitation Δ′17O has enhanced our understanding by offering new perspectives beyond those of δ18O, revealing insights into vapor sources and continental recycling. Nevertheless, there remains a lack of interannual triple oxygen isotope data, particularly in the Asian monsoon region. In this study, we analyzed the triple oxygen isotopes and hydrogen isotopes in monthly precipitation samples collected from Chongqing in Southwest China between 2019 and 2022 A.D. Seasonal variations in δD, δ18O, δ17O, and d-excess values were observed, with lower values during the rainy season and higher values during the dry season, highlighting the impact of changes in moisture sources and local meteorological conditions on seasonal shifts in δD, δ18O, and δ17O. While, mean Δ′17O values were higher in rainy season and lower in dry season. Notably, during rainy season, there is a negative correlation between monthly Δ′17O values and the RH of the vapor source area, as well as a positive correlation with d-excess. Recalculated Δ′17O values based on RH of oceanic moisture source, are higher than the measured values for this period, indicating the contribution of terrigenous moisture to precipitation in SW China. Precipitation Δ′17O values provide a more precise reflection of changes in moisture source, continental recycling, and evapotranspiration processes that drive water cycling compared Integrating modeling works in future will facilitate the use of precipitation Δ′17O values to quantify the impact of different moisture source on precipitation.
