bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hurricane Laura (2020): A Comparison of Drop Size Distribution Moments Using Ground and Radar Remote Sensing Retrieval Methods
Authors: Brauer Noah S. , Alford A. Addison , Waugh Sean M. , Biggerstaff Michael I. , Carrie Gordon D. , Kirstetter Pierre E. , Basara Jeffrey B. , Dawson Daniel T. , Elmore Kimberly L. , Stevenson Jeffrey , Moore Robert W. 
Published: August 2022

AbstractHurricane Laura was the strongest hurricane to make landfall in Louisiana since 1969 with maximum sustained winds of 130 knots. One University of Oklahoma Shared Atmospheric Mobile and Teaching Polarmetric Radar (SR1‐P), and four portable in situ precipitation stations (PIPSs) equipped with parsivel disdrometers were spatially and temporally collocated with two NASA Global Precipitation Measurement Mission Dual‐frequency Precipitation Radar overpasses. The combined retrieval methods were able to quantify and compare drop size distribution moments and radar‐inferred precipitation processes before, during, and after the storm center made landfall. It was found that the magnitude of collision‐coalescence dominant precipitation decreased from before to after landfall. Further, the presence of a bright‐band becomes more evident across all percentiles in the post‐landfall overpass, indicating an increase in stratiform precipitation compared to convective precipitation after Laura moved inland. The PIPS showed an increase in mean drop size from 1.0 mm before landfall to as high as 4.0 mm in the eyewall, while decreasing to below 1.0 mm as Laura continued to move inland with a decrease in maximum echo top height of 0.5–1.0 km. Last, the Dual‐frequency Precipitation Radar (DPR) algorithm overestimated the normalized intercept parameter by 0.5–1.0 m−3 mm−1 compared to the PIPS implying differences in measured drop number concentration, potentially due to differences in measurement footprint or assumptions in the DPR retrieval algorithm. These findings can potentially be used to improve the DPR particle size distribution algorithm in tropical cyclones.
Effect of Interdecadal Variation in Southern Indian Ocean SST on the Relationship Between ENSO and Summer Precipitation in the Asian‐Pacific Monsoon Region
Authors: Gao Ya , Chen Dong , Wang Huijun , Ma Jiehua , Wang Tao 
Published: August 2022

AbstractThe relationships between the El Niño‐Southern Oscillation (ENSO), Asian‐Pacific region summer precipitation and its corresponding atmospheric circulations exhibit interdecadal changes. From the early 1990s to the early 2000s, these relationships were significant. Therefore, we divided this time frame into three periods for analysis: 1979–1991 (P1), 1992–2005 (P2), and 2006–2019 (P3). The possible mechanism underlying these relationships is as follows: the southern Indian Ocean sea surface temperature (SST) over the east of Madagascar exhibits interdecadal variation. During P2, the SST was relatively cold, which induced an anomalously high mascarene high (MH). The strengthened MH enhanced the Somali jet and Indian monsoon westerlies, which intensified the strong center of the Indian Ocean Walker circulation. Therefore, owing to the strength and location changes of the Indian Walker circulation and the Walker circulation, the connection between the ENSO and the western Pacific vertical motions strengthened, resulting in the close relationship of the ENSO with the atmospheric circulation over the Asian‐Pacific region. Hence, ENSO can influence a north‐south tripole pattern of precipitation over the Asian‐Pacific monsoon region through local vertical activities and meridional Hadley circulation over western Pacific. Numerical experiments using an atmospheric general circulation model, with prescribed three times southern Indian Ocean SST anomalies of 1995–2005 relative to 1979–2019, also lend support to the southern Indian Ocean SST's contribution to modulating the relationship between ENSO and summer precipitation over the Asian‐Pacific monsoon region.
Experimental Determination of the Relationship Between Organic Aerosol Viscosity and Ice Nucleation at Upper Free Tropospheric Conditions
Authors: Kasparoglu Sabin , Perkins Russell , Ziemann Paul J. , DeMott Paul J. , Kreidenweis Sonia M. , Finewax Zachary , Deming Benjamin L. , DeVault Marla P. , Petters Markus D. 
Published: August 2022

AbstractThis work presents measurements of the ice nucleating ability of secondary organic material recorded between −40 and −70°C and relative humidity with respect to ice (RHice) between 150% and 220%. For a subset of systems, temperature and humidity dependence of particle viscosity as well as dry glass transition temperature were characterized using the dual tandem differential mobility analyzer method. Eleven unique monoterpene, sesquiterpene and aromatic precursors were used to generate secondary organic material (SOM) using either an oxidation flow reactor (OFR) or an environmental chamber (EC). For the SOM for which viscosity was measured, the particle glass transition temperatures varied between 6 and 23°C (n = 8). Measurements were performed to verify that increased relative humidity did not plasticize the particles below −10°C at residence times similar to those in the ice nucleation instrument. No heterogeneous ice nucleation was observed at the ∼0.5% onset threshold for any of the materials generated. The ice nucleation occurs by the freezing of SOM solution droplets consistent with homogeneous freezing indicating that they form an aqueous solution, or the SOM particles required water saturation to freeze, indicating that they were hydrophobic. Experiments exploring the influence of functional groups and mass loading did not reveal any obvious influence of particle chemistry or generation conditions on the results. Close structural matches between known organic ice nucleating particles as precursor or formed products did not yield materials that promoted freezing. These experiments suggest that heterogeneous ice formation of glassy secondary organic materials is likely uncommon under upper free tropospheric conditions.
Development and Evaluation of a New Urban Parameterization in the Weather Research and Forecasting (WRF) Model
Authors: Bhautmage Utkarsh Prakash , Fung Jimmy Chi Hung , Pleim Jonathan , Wong Michael Mau Fung 
Published: August 2022

AbstractIn mesoscale Weather Research and Forecasting (WRF) model, several urban‐modeling options exist, such as Single‐layer Urban Canopy Model, Building Effect Parameterization, and Building Energy Model. However, these models have limitations in terms of the choice of land surface models (LSMs) and planetary boundary layer (PBL) schemes, the associated computational expenses, and other constraints. Recently, Dy et al. (2019, https://doi.org/10.1029/2018JD029333) included the urban‐momentum drag effect for wind‐speed modeling by developing a new multilayer model based on a modified nonlocal Asymmetric Convective Model version‐2 (ACM2) PBL scheme. This urban‐based ACM2 (UACM) has demonstrated a significantly improved ability over the base‐ACM2 (BACM) to predict wind speed near the urban ground surface and shown an inflection point at roof level in the vertical profile of horizontal wind. In this study, urban thermal and moisture components are introduced into the Pleim‐Xiu (PX) LSM and coupled with UACM. The diurnal variation in street, walls, and roof‐surface temperatures is modeled using the two‐layer force‐restore algorithm. Simple radiation treatment is considered to account for shadowing on streets based on the solar zenith angle and building morphology. Heat and moisture flux evolution are considered explicitly on all urban surfaces. The advantages of this novel UACM are simple formulation, more efficient execution, and its requirement for only a few fundamental urban morphological parameters. The idealized and real urban data case WRF simulations are performed over the Pearl River Delta region in southern China to test the new UACM. The computationally efficient UACM is expected to perform faster for operational forecasting runs.
Microphysical Piggybacking in the Weather Research and Forecasting Model
Authors: Sarkadi Noémi , Xue Lulin , Grabowski Wojciech W. , Lebo Zachary J. , Morrison Hugh , White Bethan , Fan Jiwen , Dudhia Jimy , Geresdi István 
Published: August 2022

AbstractThis paper presents incorporation of the microphysical piggybacking into the Weather Research and Forecasting (WRF) model. Microphysical piggybacking is to run a single simulation applying two microphysical schemes, the first scheme driving the simulation and the second piggybacking this simulated flow. “Driving the simulation” means that the simulated microphysical processes, affect the cloud buoyancy and thus force the simulated flow. In contrast, the piggybacking variables are advected by the simulated flow and undergo microphysical transformation, but they do not affect the simulated flow (like in prescribed flow—kinematic—simulations). The two sets of variables (driver and piggybacker) include temperature, water vapor mixing ratio, and all microphysical variables. We provide details of implementing piggybacking into the WRF model, illustrate its applications, and demonstrate the benefits of this methodology in two idealized three‐dimensional cases: (a) a squall line case applying two microphysics schemes, the Thompson bulk microphysics scheme and the University of Pécs/NCAR bin (UPNB) scheme. The piggybacking simulations revealed that the microphysics‐dynamics interaction plays a more important role than the pure microphysical size sorting effect in the transition zone formation. (b) A case of daytime shallow‐to‐deep convective development over land. This case uses the UPNB scheme and contrasts convection developing in environments with either pristine or polluted cloud condensation nuclei (CCN). The piggybacking results indicated that the increase of cloud cover and decrease of supersaturation are mainly associated with the microphysical effect of increasing CCN while the change of precipitation on the ground is also influenced by microphysics‐dynamics interactions.
The Effects of Numerical Dissipation on Hurricane Rapid Intensification With Observational Heating
Authors: Hasan M. B. , Guimond S. R. , Yu M. L. , Reddy S. , Giraldo F. X. 
Published: August 2022

AbstractThe computational fluid dynamics of hurricane rapid intensification (RI) is examined through idealized simulations using two codes: a community‐based, finite‐difference/split‐explicit model (WRF) and a spectral‐element/semi‐implicit model (NUMA). The focus of the analysis is on the effects of implicit numerical dissipation (IND) in the energetics of the vortex response to heating, which embodies the fundamental dynamics in the hurricane RI process. The heating considered here is derived from observations: four‐dimensional, fully nonlinear, latent heating/cooling rates calculated from airborne Doppler radar measurements collected in a hurricane undergoing RI. The results continue to show significant IND in WRF relative to NUMA with a reduction in various intensity metrics: (a) time‐integrated, mean kinetic energy values in WRF are ∼20% lower than NUMA and (b) peak, localized wind speeds in WRF are ∼12 m/s lower than NUMA. Values of the eddy diffusivity in WRF need to be reduced by ∼50% from those in NUMA to produce a similar intensity time series. Kinetic energy budgets demonstrate that the pressure contribution is the main factor in the model differences with WRF producing smaller energy input to the vortex by ∼23%, on average. The low‐order spatial discretization of the pressure gradient in WRF is implicated in the IND. In addition, the eddy transport term is found to have a largely positive impact on the vortex intensification with a mean contribution of ∼20%. Overall, these results have important implications for the research and operational forecasting communities that use WRF and WRF‐like numerical models.
Variations on a Pathway to an Early Eocene Climate
Authors: Henry Matthew , Vallis Geoffrey K. 
Published: August 2022

AbstractThe climate of the early Eocene was characterized by much higher temperatures and a smaller equator‐to‐pole surface temperature gradient than today. Comprehensive climate models have been reasonably successful in simulating that climate in the annual average. However, good simulations of the seasonal variations, and in particular much warmer Arctic winters over land, have proven more difficult. Further, while increased greenhouse gases seems necessary to achieve an Eocene climate, it is unclear whether there is a unique combination of factors that leads to agreement with all available proxies. Here we use a very flexible General Circulation Model to examine the sensitivity of the modeled climate to differences in CO2 concentration, land surface properties, ocean heat transport, and cloud extent and thickness. Even in the absence of ice or changes in cloudiness, increasing the CO2 concentration leads to a polar‐amplified surface temperature change because of increased water vapor levels combined with the lack of convection at high latitudes, with the nonlinear dependence of longwave radiation on temperature amplifying the increase in winter over land. Additional low clouds over Arctic land generally decrease summer temperatures and further increase winter temperatures (except at very high CO2 levels). An increase in the land surface heat capacity, plausible given large changes in vegetation, also decreases the Arctic land seasonality. Thus, different combinations of factors—high CO2 levels, changes in low‐level clouds, and an increase in land surface heat capacity—can lead to a simulation within the proxy uncertainty range of the majority of proxy data.
Per‐ and Polyfluoroalkyl Substances (PFAS) in Subsurface Environments: Occurrence, Fate, Transport, and Research Prospect
Authors: Lyu Xueyan , Xiao Feng , Shen Chongyang , Chen Jingjing , Park Chang Min , Sun Yuanyuan , Flury Markus , Wang Dengjun 
Published: August 2022

AbstractPer‐ and polyfluoroalkyl substances (PFASs), also known as “forever chemicals,” are manmade chemicals that have been increasingly detected in various geological settings since the early 2000s. The soil and subsurface environments are the geological media commonly affected by PFAS. We conducted a comprehensive review of peer‐reviewed articles published from 2010 through 2022 concerning the fate and transport of PFAS in subsurface environments. This review is organized into different subsections, covering the basics of PFAS properties and how they affect the occurrence, fate, and transport of PFAS, the fundamental processes affecting subsurface transport and fate of PFAS, and mathematical models for describing and predicting PFAS transport behaviors. Mechanisms governing PFAS transport in the subsurface environment, including the sorption of PFAS at the air‐water interface, solid‐water interface, and nonaqueous phase liquids‐water interface, were explored in detail. Challenges and future research priorities are identified to better mitigate the global challenges of PFAS contamination.
Structural Architecture and Attenuation of the Ductile Lower Plate of the Ruby Mountain‐East Humboldt Range Metamorphic Core Complex, Northeast Nevada
Authors: Zuza Andrew V. , Levy Drew A. , Dee Seth , DesOrmeau Joel W. , Cheng Feng , Li Xiangzhong 
Published: August 2022

AbstractStrongly deformed footwall rocks exposed in metamorphic core complexes (MCC) of the North American Cordillera were exhumed via ductile attenuation, mylonitic shearing, and detachment faulting. Whether these structures accommodated diapiric upwelling or regional extension via low‐angle normal faulting is debated. The Ruby Mountains‐East Humboldt Range MCC, northeast Nevada, records top‐west normal‐sense exhumation of deformed Proterozoic‐Paleozoic stratigraphy and older basement. We conducted 1:24,000‐scale mapping of the southwestern East Humboldt Range, with integrated structural, geochemical, and geochronological analyses to characterize the geometry and kinematics of extension and exhumation of the mylonitized footwall. Bedrock stratigraphy is pervasively intruded by Cretaceous, Eocene, and Oligocene intrusions, but observations of a coherent stratigraphic section show >80% vertical attenuation of Neoproterozoic to Ordovician rocks. These rocks are penetratively sheared with top‐west kinematics. The shear zone thus experienced combined pure‐ and simple‐shear (i.e., general shear) strain. We argue that this shear zone was syn‐/post‐kinematic with respect to Oligocene plutonism because: (a) mylonitic shearing spatially corresponds with preceding Oligocene intrusions; (b) thermochronology reveals that the shear zone experienced substantial cooling and exhumation after Oligocene plutonism; and (c) the mylonites are crosscut by undated, but likely late Oligocene, leucogranite. We propose that Eocene mantle‐derived magmatism and thermal incubation led to Oligocene diapiric upwelling of the middle crust, with ductile stretching focused on the flanks of this upwarp. Regional Basin and Range extension initiated later in the middle Miocene. Therefore, the development of the East Humboldt Range shear zone was not driven by regional extension and coupled detachment faulting.
Dynamics of Unusual Extreme Rainfall Events Over Different Altitudes Using Richardson Number
Authors: Ullah Kalim , Ikram Farah 
Published: August 2022

AbstractTo delineate the dynamic stability of a moist atmosphere and to measure stability within a statically stable atmosphere, local Richardson number (Ri) and Brunt‐Väisälä (BV) frequency are used in this study. The BV frequency is an important parameter that is widely used in dynamic meteorology and is calculated by replacing potential temperature with equivalent potential temperature in a moist atmosphere. For this purpose, extreme rainfall events were simulated by the WRF model. These events occurred on 9 September 2012 and 28 July 2010 during the summer monsoon in areas of different altitudes (ranging approximately from 100 to 3,500 m) which resulted in flash floods, loss of lives, and property damages in southern and northern parts of Pakistan. In the present case Ri (local Richardson number based on potential temperature) and Rie (local Richardson number based on equivalent potential temperature) are applied to investigate instability (Rie < 1) in a moist atmosphere. The results show that the values of Rie < 1 are mainly located in the lower‐to‐upper troposphere over the rainfall areas. The analysis shows that Rie is more suitable index for describing the convective instability in a moist saturated atmosphere. The results of Ri and Rie were justified with the European Centre for Medium‐Range Weather Forecasts fifth generation reanalysis (ERA5 hourly) available from Climate Data Store. Moreover, negative values of vertical velocity (hPa/s) clearly show large‐scale dynamical uplifting associated with instability resulting in a severe thunderstorm. Further, strong synoptic forcings also play a key role to develop deep convection over the region. In addition, maximum convective available potential energy (3,000 J/kg) and K‐index (>40) were observed over the areas of high instability that dominate its role in enhancing convection during the events.
Mitigation Strategies to Improve Reproducibility of Poverty Estimations From Remote Sensing Images Using Deep Learning
Authors: Machicao J. , Ben Abbes A. , Meneguzzi L. , Corrêa P. L. P. , Specht A. , David R. , Subsol G. , Vellenich D. , Devillers R. , Stall S. , Mouquet N. , Chaumont M. , Berti‐Equille L. , Mouillot D. 
Published: August 2022

AbstractThe challenges of Reproducibility and Replicability (R & R) in computer science experiments have become a focus of attention in the last decade, as efforts to adhere to good research practices have increased. However, experiments using Deep Learning (DL) remain difficult to reproduce due to the complexity of the techniques used. Challenges such as estimating poverty indicators (e.g., wealth index levels) from remote sensing imagery, requiring the use of huge volumes of data across different geographic locations, would be impossible without the use of DL technology. To test the reproducibility of DL experiments, we report a review of the reproducibility of three DL experiments which analyze visual indicators from satellite and street imagery. For each experiment, we identify the challenges found in the data sets, methods and workflows used. As a result of this assessment we propose a checklist incorporating relevant FAIR principles to screen an experiment for its reproducibility. Based on the lessons learned from this study, we recommend a set of actions aimed to improve the reproducibility of such experiments and reduce the likelihood of wasted effort. We believe that the target audience is broad, from researchers seeking to reproduce an experiment, authors reporting an experiment, or reviewers seeking to assess the work of others.
Relative Timing of Off‐Axis Volcanism From Sediment Thickness Estimates on the 8°20’N Seamount Chain, East Pacific Rise
Authors: Fabbrizzi Andrea , Parnell‐Turner Ross , Gregg Patricia M. , Fornari Daniel J. , Perfit Michael R. , Wanless V. Dorsey , Anderson Molly 
Published: August 2022

AbstractVolcanic seamount chains on the flanks of mid‐ocean ridges record variability in magmatic processes associated with mantle melting over several millions of years. However, the relative timing of magmatism on individual seamounts along a chain can be difficult to estimate without in situ sampling and is further hampered by Ar40/Ar39 dating limitations. The 8°20’N seamount chain extends ∼170 km west from the fast‐spreading East Pacific Rise (EPR), north of and parallel to the western Siqueiros fracture zone. Here, we use multibeam bathymetric data to investigate relationships between abyssal hill formation and seamount volcanism, transform fault slip, and tectonic rotation. Near‐bottom compressed high‐intensity radiated pulse, bathymetric, and sidescan sonar data collected with the autonomous underwater vehicle Sentry are used to test the hypothesis that seamount volcanism is age‐progressive along the seamount chain. Although sediment on seamount flanks is likely to be reworked by gravitational mass‐wasting and current activity, bathymetric relief and Sentry vehicle heading analysis suggest that sedimentary accumulations on seamount summits are likely to be relatively pristine. Sediment thickness on the seamounts' summits does not increase linearly with nominal crustal age, as would be predicted if seamounts were constructed proximal to the EPR axis and then aged as the lithosphere cooled and subsided away from the ridge. The thickest sediments are found at the center of the chain, implying the most ancient volcanism there, rather than on seamounts furthest from the EPR. The nonlinear sediment thickness along the 8°20’N seamounts suggests that volcanism can persist off‐axis for several million years.