bluuebunny/crossref_metadata_2025 huggingface dataset:
All-cause mortality and disease progression in SARS-CoV-2-infected patients with or without antibiotic therapy: an analysis of the LEOSS cohort
Authors: Schons Maximilian J. , Caliebe Amke , Spinner Christoph D. , Classen Annika Y. , Pilgram Lisa , Ruethrich Maria M. , Rupp Jan , Nunes de Miranda Susana M. , Römmele Christoph , Vehreschild Janne , Jensen Bjoern-Erik , Vehreschild Maria , Degenhardt Christian , Borgmann Stefan , Hower Martin , Hanses Frank , Haselberger Martina , Friedrichs Anette K. ,   the LEOSS-study group, Lanznaster Julia , Spinner Christoph D. , Ruethrich Maria Madeleine , Jensen Bjoern-Erik , Hower Martin , Rupp Jan , Roemmele Christoph , Vehreschild Maria , Degenhardt Christian , Borgmann Stefan , Hanses Frank , Hellwig Kerstin , Dahl Jürgen vom , Dolff Sebastian , Piepel Christiane , Kielstein Jan , Nadalin Silvio , Neufang Marc , Milovanovic Milena , Wille Kai , Rothfuss Katja , Eberwein Lukas , Rimili Wolfgang , Westhoff Timm , Worm Maximilian , Beutel Gernot , Jung Norma , Schubert Joerg , Markart Philipp , Rueddel Jessica , Voigt Ingo , Bals Robert , Raichle Claudia , Vehreschild Jörg Janne , Jakob Carolin E. M. , Pilgram Lisa , Stecher Melanie , Schons Maximilian , de Miranda Susana M. Nunes , Schulze Nick , Fuhrmann Sandra , Brünn Clara , Claßen Annika , Franke Bernd , Praßer Fabian , Lablans Martin
Published: October 2021

Purpose

Reported antibiotic use in coronavirus disease 2019 (COVID-19) is far higher than the actual rate of reported bacterial co- and superinfection. A better understanding of antibiotic therapy in COVID-19 is necessary.

Methods

6457 SARS-CoV-2-infected cases, documented from March 18, 2020, until February 16, 2021, in the LEOSS cohort were analyzed. As primary endpoint, the correlation between any antibiotic treatment and all-cause mortality/progression to the next more advanced phase of disease was calculated for adult patients in the complicated phase of disease and procalcitonin (PCT) ≤ 0.5 ng/ml. The analysis took the confounders gender, age, and comorbidities into account.

Results

Three thousand, six hundred twenty-seven cases matched all inclusion criteria for analyses. For the primary endpoint, antibiotic treatment was not correlated with lower all-cause mortality or progression to the next more advanced (critical) phase (n = 996) (both p > 0.05). For the secondary endpoints, patients in the uncomplicated phase (n = 1195), regardless of PCT level, had no lower all-cause mortality and did not progress less to the next more advanced (complicated) phase when treated with antibiotics (p > 0.05). Patients in the complicated phase with PCT > 0.5 ng/ml and antibiotic treatment (n = 286) had a significantly increased all-cause mortality (p = 0.029) but no significantly different probability of progression to the critical phase (p > 0.05).

Conclusion

In this cohort, antibiotics in SARS-CoV-2-infected patients were not associated with positive effects on all-cause mortality or disease progression. Additional studies are needed. Advice of local antibiotic stewardship- (ABS-) teams and local educational campaigns should be sought to improve rational antibiotic use in COVID-19 patients.
Fear-Related Reasons for Avoiding Sexual Intercourse in Early Pregnancy: A Cross-Sectional Study
Authors: Phan Thanh C. , Hoang Long B. , Tran Thanh K. , Pham Trang T.T. , Bui Anh V. , Dao Hoa T. , Ngo Toan V. , Tran Cuong D.
Published: October 2021

Introduction

Several studies have reported women's worry that sexual intercourse may harm the course of pregnancy. This worry might lead to avoidance of sexual intercourse during pregnancy.

Aim

To assess if fears about harming the pregnancy are associated with avoidance of sexual intercourse during pregnancy.

Methods

A cross-sectional study was conducted on 250 Vietnamese pregnant women in the first or second trimester who visited our hospital for antenatal care. We explored 5 types of fears including miscarriage/preterm labor, premature rupture of membranes, bleeding, infection, and injury to the fetus. Fears were measured by modified questions from the Reasons For Not Engaging in Sexual Activity During Pregnancy questionnaire. Using the total fear score, pregnant women were categorized into having low, moderate, and high fear.

Main Outcome Measure

Not having sexual intercourse during the past 4 weeks.

Results

72 (28.8%) pregnant women had no sexual intercourse for the past 4 weeks. All types of fear were considered important among pregnant women; the more important fears were infection and injury to the fetus. In multivariable regression analysis, the prevalence of not having sexual intercourse was higher in both women who had moderate (adjusted prevalence ratio = 2.84, 95% CI 1.42–5.67) and high fear (adjusted prevalence ratio = 4.39, 95% CI 2.28–8.44).

Conclusion

Avoidance of sexual intercourse was common among Vietnamese pregnant women and was associated with the fears about harming the pregnancy. This can be a target in the health education programs for pregnancy couples.
The Relationship Between Pelvic Floor Function and Sexual Function in Perimenopausal Women
Authors: Zhuo Zhihong , Wang Chuhan , Yu Huimin , Li Jing
Published: October 2021

Introduction

Perimenopausal women with pelvic floor dysfunction have worse sexual function than women with functional pelvic floor muscle (PFM), especially in terms of libido, orgasm, sexual satisfaction, and total Female Sexual Function Index (FSFI) scores.

Aim

To explore the relationship between pelvic floor muscle function, hormone levels and sexual function in perimenopausal women.

Methods

An analytical cross-sectional study was conducted in 252 women aged 40–55 without pelvic floor disease with FSFI, pelvic floor muscle strength and the hormone levels.

Main Outcome Measure

The principle aim was to determine the relationships between sexual dysfunction, PFM strength, and hormone levels.

Results

In the functional PFM group, the proportion of menopausal hormone therapy was higher. The proportion of overweight in the dysfunctional PFM group was higher, and had more sexual desire disorder, more orgasm disorder, lower sexual satisfaction, and poor FSFI scores. The correlation between PFM strength, sexual function and female sex hormones suggested that PFM strength and libido, sexual satisfaction and FSFI score are significantly positively correlated, while PFM strength and sexual arousal disorder and vaginal lubricity had a positive correlation. In the multivariate analysis of the risk of sexual dysfunction among perimenopausal women, the higher the PFM strength, the lower the risk of sexual dysfunction.

Conclusions

Perimenopausal women with pelvic floor dysfunction have worse sexual function than women with functional PFM, especially in obese women, those with central adiposity, and not using hormone replacement therapy. The PFM strength was weakly positively correlated with sexual arousal, orgasm, sexual satisfaction, and FSFI score.
Successful Non-Extracorporeal Rewarming from Hypothermic Cardiac Arrest: 2 Cases
Authors: Cools Evelien , Latscher Helmut , Ströhle Mathias , Paal Peter
Published: October 2021

Accidental hypothermia (core temperature <35°C) is a complication in persons who have fallen into crevasses; hypothermic cardiac arrest is the most serious complication. Extracorporeal life support (ECLS) is the optimal method for rewarming hypothermic cardiac arrest patients, but it may not be readily available and non-ECLS rewarming may be required. We report the medical course of 2 patients with hypothermic cardiac arrest, each of whom had fallen into a crevasse. They were treated successfully with non-ECLS rewarming using peritoneal and thoracic lavage. We discuss non-ECLS treatment options for hypothermic cardiac arrest and describe successful non-ECLS rewarming in an outlying hospital without ECLS rewarming capability in the Grossglockner region of Austria in 1990 and 2003. Both patients survived neurologically intact. Non-ECLS rewarming in a trauma center without ECLS capabilities is feasible and can result in a good outcome when ECLS is not available. The best non-ECLS rewarming method for hypothermic cardiac arrest patients has not yet been established. Non-ECLS rewarming should be adapted to local capabilities. To obtain more robust evidence, it seems reasonable to pool data on the treatment and outcome of non-ECLS rewarming in hypothermic cardiac arrest patients.
The Associations Between Visitation, Social Media Use, and Search and Rescue in United States National Parks
Authors: Lu Zachary N. , Briggs Amy , Saadat Soheil , Algaze Isabel M.
Published: October 2021

Introduction

Search and rescue (SAR) is vital for visitor safety in US national parks, which are popular destinations for tourists. Previous studies have described SAR and seasonal visitation patterns, but not in the context of overall visitation. In addition, studies on the association between SAR and developed park areas remain limited. Concurrently, social media can be valuable for sharing information about conservation awareness and the joy of being outdoors. However, social media can potentially be an avenue for users to share risky and dangerous behaviors performed during attempts to obtain photos and videos. The associations between SAR and social media have not been discussed in existing literature.

Methods

Variables included recreational visits, developed site stay visits, backcountry visits, SAR incidents, and tweets. Data from 2017 were obtained from National Park Service visitor use statistics, the SAR incident dashboard, and the University of California, Irvine, Cloudberry application. Correlation analysis was performed using nonparametric Kendall rank correlation coefficients.

Results

Recreational visits were correlated with SAR incidents (rτ=0.415, P<0.001). Developed site stays were similarly correlated with SAR incidents (rτ=0.447, P<0.001), as were backcountry visits (rτ=0.428, P<0.001). Backcountry visits had a stronger correlation with fatalities (rτ=0.380, P<0.001) compared to developed site stays (rτ=0.304, P<0.001). Tweets were correlated with SAR incidents (rτ=0.468, P<0.001), recreational visits (rτ=0.403, P<0.001), and fatalities (rτ=0.367, P<0.001).

Conclusions

Our findings demonstrate associations between national park visitation, SAR incidents, fatalities, and Twitter use and provides a concept framework for future prospective studies to further investigate the relationships between visitation, SAR, and social media.
Imaging Elastodynamic and Hydraulic Properties of In Situ Fractured Rock: An Experimental Investigation Exploring Effects of Dynamic Stressing and Shearing
Authors: Wood Clay E. , Shokouhi Parisa , Manogharan Prabhakaran , Rivère Jacques , Elsworth Derek , Marone Chris
Published: October 2021

We describe laboratory experiments to elucidate the relationship between nonlinear elasticity and permeability evolution in fractured media subjected to local stress perturbations. This study is part of an effort to measure fluid pathways and fracture properties using active‐source acoustic monitoring during fluid injection and shear of rough fractures. Experiments were conducted with L‐shaped samples of Westerly granite fractured in situ under triaxial conditions with deionized water subsequently circulated through the resulting fractures. After in situ fracturing, we separately imposed oscillations of the applied normal stress and pore pressure with amplitudes ranging from 0.2 to 1 MPa and frequencies from 0.1 to 40 Hz. In response to normal stress and pore pressure oscillations, fractured Westerly granite samples exhibit characteristic transient softening, acoustic velocity fluctuations, and slow recovery, together with permeability enhancement or decay, informing us about the coupled nonlinear elastodynamic and poromechanical rock properties. Fracture interface properties (contact asperity stiffness, aperture) are then altered in situ by shearing, which generally decreases the measured elastic nonlinearity and permeability change for both normal stress and pore pressure oscillations.
Volume Budget of Subantarctic Mode Water in the Southern Ocean From an Ocean General Circulation Model
Authors: Jing Wandi , Luo Yiyong
Published: October 2021

The volume budget of Subantarctic Mode Water (SAMW) in the Southern Ocean (SO) is examined using a 0.1° ocean model output from 1950 to 2017. The results show that air–sea buoyancy fluxes, advective exports, and diapycnal mixing are all important to the SAMW volume budget. A climatological mean analysis finds that, for the SO as a whole, water in the SAMW density range ( kg m−3) is balanced between the following: formation due to air–sea buoyancy fluxes ( Sv), removal due to advective export northward out of the SO ( Sv), destruction due to diapycnal mixing ( Sv), and storage ( Sv). Decadal changes in the SAMW volume in the Indian and Pacific sectors display a two‐layer density structure, in which the volumes of the upper and lower layers vary predominantly out of phase with each other. In addition, the SAMW volume changes in the Indian and Pacific sectors appear to compensate each other on decadal time scales. The volume of SAMW in the SO has increased by ∼11% since the 1950s, and this increase tends to emerge gradually from denser to lighter layers. The increased SAMW volume mainly results from a consistent increase in oceanic buoyancy gain over the outcropping area at approximately 27.1 .
The Role of Intensifying Precipitation on Coastal River Flooding and Compound River‐Storm Surge Events, Northeast Gulf of Mexico
Authors: Dykstra S. L. , Dzwonkowski B.
Published: October 2021

Destructive coastal floods are commonly increasing in frequency and may be caused by global precipitation intensification. Such connections through climate, watershed, and river processes are poorly understood because of complex interactions in transitional fluvial‐marine environments where flooding is caused by rivers, marine storm surge, or both in compound events. To better understand river floods along the fluvial‐marine transition, we study watersheds of the northeastern Gulf of Mexico using long‐term observations. Results show intensifying precipitation decreased precipitation‐discharge lag times, increasing river‐flood frequency and the likelihood of compound events in fluvial‐marine transitions. This reduction in lag time occurred when the Atlantic Multidecadal Oscillation and El Niño Southern Oscillation began strongly affecting river discharge through the advection of moist air, intensifying precipitation. Along the fluvial‐marine transition, compound events were largest in inland reaches. However, for inland reaches, compound event water levels did not exceed the floods caused solely by river flooding, the largest flood hazard in these systems. Our results demonstrate precipitation and river discharge play critical roles in coastal flooding and will likely escalate flooding as the climate continues to warm and intensify precipitation.
Seasonality and Life History Complexity Determine Vulnerability of Dungeness Crab to Multiple Climate Stressors
Authors: Berger Halle M. , Siedlecki Samantha A. , Matassa Catherine M. , Alin Simone R. , Kaplan Isaac C. , Hodgson Emma E. , Pilcher Darren J. , Norton Emily L. , Newton Jan A.
Published: October 2021

Scaling climate change impacts from individual responses to population‐level vulnerability is a pressing challenge for scientists and society. We assessed vulnerability of the most valuable fished species in the Northwest U.S.—Dungeness crab—to climate stressors using a novel combination of ocean, population, and larval transport models with stage‐specific consequences of ocean acidification, hypoxia, and warming. Integration across pelagic and benthic life stages revealed increased population‐level vulnerability to each stressor by 2100 under RCP 8.5. Under future conditions, chronic vulnerability to low pH emerged year‐round for all life stages, whereas vulnerability to low oxygen continued to be acute, developing seasonally and impacting adults, which are critical to population growth. Our results demonstrate how ontogenetic habitat shifts and seasonal ocean conditions interactively impact population‐level vulnerability. Because most valuable U.S. fisheries rely on species with complex life cycles in seasonal seas, chronic and acute perspectives are necessary to assess population‐level vulnerability to climate change.
Patched Local Lunar Gravity Solutions Using GRAIL Data
Authors: Goossens Sander , Fernández Mora Álvaro , Heijkoop Eduard , Sabaka Terence J.
Published: October 2021

We present a method to determine local gravity fields for the Moon using Gravity Recovery and Interior Laboratory (GRAIL) data. We express gravity as gridded gravity anomalies on a sphere, and we estimate adjustments to a background global start model expressed in spherical harmonics. We processed GRAIL Ka‐band range‐rate data with a short‐arc approach, using only data over the area of interest. We determine our gravity solutions using neighbor smoothing constraints. We divided the entire Moon into 12 regions and 2 polar caps, with a resolution of (which is equivalent to degree and order 1199 in spherical harmonics), and determined the optimal smoothing parameter for each area by comparing localized correlations between gravity and topography for each solution set. Our selected areas share nodes with surrounding areas and they are overlapping. To mitigate boundary effects, we patch the solutions together by symmetrically omitting the boundary parts of overlapping solutions. Our new solution has been iterated, and it has improved correlations with topography when compared to a fully iterated global model. Our method requires fewer resources, and can easily handle regionally varying resolution or constraints. The smooth model describes small‐scale features clearly, and can be used in local studies of the structure of the lunar crust.
Adapting to Receding Glaciers in the Tropical Andes
Authors: Rojas Tania , Quincey Duncan , Rau Pedro , Horna-Mu�oz Daniel , Abad Jorge
Published: October 2021

Integrated approaches are needed to understand and respond to changes in tropical mountain ecosystems and communities brought about by receding glaciers and changes in land use.
Raman Spectral Shifts in Naturally Faulted Rocks
Authors: Muirhead D. K. , Kedar L. , Schito A. , Corrado S. , Bond C. E. , Romano C.
Published: October 2021

Raman spectral shifts of carbonaceous materials arising from faulted rocks produce varied and complex results. By analyzing faulted and adjacent non‐faulted samples from three discrete localities in France, Italy, and Morocco, we assess changes in specific Raman parameters, including G‐peak width, G‐peak position, and peak intensity ratios. We consistently observe a shift in Raman parameters between faulted and non‐faulted samples; however, the direction and magnitude of this shift varies. Raman peak intensity ratios are shown to both increase and decrease on fault planes. The majority of samples exhibit decreasing peak width and peak position in the faulted samples, but this is not consistent; in two samples an increase is observed, but the shift tends to be small. These data are compared to published Raman spectral shifts from experimental fault data. Our results suggest that fault zone deformation processes may measurably change the carbon nanostructure in faulted rocks. The inconsistent nature of Raman spectral shifts in the fault rock samples analyzed, and those published suggest that a complex set of factors control carbon nanostructure changes in fault rocks. These factors, although not discriminated here, likely include, background temperature, frictional heating, strain, carbonaceous material type, amongst others. We have shown that Raman Spectral shifts occur in faulted rocks with implications for how Raman data are used to predict maximum temperatures in faulted sedimentary rocks. We recognize the potential for a range of fault zone processes to modify Raman spectral shifts, however, systematic sampling across individual fault zones is critical.
Variability in Timing and Transport of Pleistocene Meltwater Recharge to Regional Aquifers
Authors: Mowat Aidan C. , Francis Daniel J. , McIntosh Jennifer C. , Lindsay Matthew B. J. , Ferguson Grant A. G.
Published: October 2021

The impacts of Pleistocene glaciation on groundwater flow systems in sedimentary basins are widely recognized, but the timing and distribution of subglacial recharge events remain poorly constrained. We investigate the spatial and temporal variability of recharge events from glaciations over the last 2 million years in the Williston Basin, Canada. Integration of fluid chemistry, stable isotope data, and transport modeling indicate that meltwater arrived at depths of ∼600–1000 m in the northcentral region of the Williston Basin at two separate time periods, 75–150 and 300 ka, which we attribute to permeability differences between stacked aquifer systems. Our findings indicate that meltwater recharge extended along the northern margin of the Williston Basin as well as previously identified recharge areas to the east. Given the distance of measurements from recharge areas, evidence of recharge from the early to mid‐Pleistocene appears to be preserved in the Williston Basin.
Compound Parameterization to Improve the Accuracy of Radiation Emulator in a Numerical Weather Prediction Model
Authors: Song Hwan‐Jin , Roh Soonyoung , Park Hyesook
Published: October 2021

To improve the numerical weather prediction model over Korea using a neural network (NN) radiation emulator, two types of compound parameterization (CP) were developed. Although the CP returning to the original parameterization causes a considerable increase in the computational time, this increase can be compensated by the infrequent use of the radiation scheme, thus maintaining the 60‐fold speedup of the radiation process with the NN emulator. The first CP is based on the prediction of the heating rate error using the additional NN for all given input variables. In contrast, the second CP uses the cloud fraction to estimate the uncertainty of the NN emulator. As a result of model simulations for independent cases, including extreme flood events, the first CP was the most effective for passive use, whereas the second was useful in active use and exhibited the lowest error. Thus, these CP methods can help improve weather forecasting.
Ultra‐Thick Paleoregolith Layer Detected by Lunar Penetrating Radar: Implication for Fast Regolith Formation Between 3.6 and 2.35 Ga
Authors: Zhu Tieyuan , Zhang Jinhai , Lin Yangting
Published: October 2021

Lunar paleoregolith was formed by repeated asteroid impact and space weathering and then buried by later lava flows, serving as important records for early solar system history. However, direct observational evidence for the paleoregolith layer is rather limited. We present the evidence for the existence of the paleoregolith layer by processing 60 MHz lunar penetrating radar data acquired by the Chang’E‐3 Yutu rover. We find successive reflections with reversed polarities due to a low permittivity (paleoregolith) layer sandwiched in two high permittivity (lava) layers. From modeling and migration imaging of radar reflections, we determine an ultra‐thick paleoregolith layer (∼5–9 m) beneath the Eratosthenian unit and on the top of the Imbrian unit, suggesting a high regolith production rate of 5.8–10.5 m/Ga between late Imbrian and early Eratosthenian periods compared to the previous estimation ∼2 m/Ga, implying fast regolith formation and possible high meteoric flux during these periods.
A Tale of Two Radiation Belts: The Energy‐Dependence of Self‐Limiting Electron Space Radiation
Authors: Olifer L. , Mann I. R. , Kale A. , Mauk B. H. , Claudepierre S. G. , Baker D. N. , Spence H. E. , Ozeke L. G.
Published: October 2021

The flux of energetic electrons in the terrestrial Van Allen Belts varies by orders of magnitude during a magnetic storm. Here, we show how the dynamics of these electrons are clearly separated by energy into two distinct populations which are governed by different storm time behavior. We reveal how self‐limiting processes, described theoretically by Kennel and Petschek (1966), https://doi.org/10.1029/JZ071i001p00001, govern the energy‐dependent dynamics of the electrons. For terrestrial magnetic storms, accelerated electrons with energies below 850 keV quickly reach a maximum energy‐dependent differential flux level which is almost the same in every storm. Higher energy electrons typically do not reach a limiting flux and instead are governed by the differential impacts of competing acceleration and loss mechanisms. In general, electron fluxes saturate at the Kennel‐Petschek limit first at lower energies, impacting higher energies later in the storm. For the most intense storms, the maximum energy at which the fluxes are capped can also increase.
An Investigation of Auroral E Region Energy Exchange Using Poker Flat Incoherent Scatter Radar Observations During Fall Equinox Conditions
Authors: Zhan Weijia , Kaeppler Stephen R. , Larsen Miguel F. , Reimer Ashton , Varney Roger
Published: October 2021

We present new results using data collected by the Poker Flat Incoherent Scatter Radar (PFISR) of energy transfer rates, which include the effects from neutral winds in the high latitude E‐region ionosphere‐thermosphere (IT) during Fall 2015. The purpose of our investigation is to understand the magnetic local time (MLT) dependence of the peak energy transfer, which occurs asymmetrically in the morning‐evening (dawn‐dusk) MLT sector. The statistical characteristics of both altitude‐resolved and altitude‐integrated energy transfer rates in the auroral E region local to PFISR during different geomagnetic conditions are quantified. Our analysis shows that the geomagnetic activity level has large impacts on the energy transfer rates. In contrast with previous investigations, we find both the altitude integrated electromagnetic (EM) energy transfer rate and Joule heating rate are larger in the evening sector than in the morning sector during all geomagnetic activity conditions. We also observe a non‐negligible negative EM energy transfer rates below 110 km in the morning sector during active conditions, which is associated with neutral winds during this MLT interval. The statistical results show that the neutral winds tend to increase the Joule heating rate in a narrow altitude range in the morning sector and impact a broader region with respect to altitude and time in the evening sector in the E region under moderate and active conditions. We find that during quiet conditions that the neutral winds have a significant contribution to the Joule heating and contribute up to 75% of the Joule heating. However, during active conditions the enhanced electric fields are a dominant driver of Joule heating, while the neutral wind effects can reduce the Joule heating rates by 25% or more relative to the passive heating rates.
MAVEN Observations of Low Frequency Steepened Magnetosonic Waves and Associated Heating of the Martian Nightside Ionosphere
Authors: Fowler C. M. , Hanley K. G. , McFadden J. P. , Chaston C. C. , Bonnell J. W. , Halekas J. S. , Espley J. R. , DiBraccio G. A. , Schwartz S. J. , Mazelle C. , Mitchell D. L. , Xu S. , Lillis R. J.
Published: October 2021

We present Mars Atmosphere and Volatile EvolutioN (MAVEN) observations of low frequency steepened fast magnetosonic waves in the Martian magnetosphere and ionosphere. Solar wind pressure pulses generated in the upstream foreshock region impact the magnetopause and generate the magnetosonic waves within the magnetosphere, in a process analogous to the production of magnetic Pc pulsations in the terrestrial magnetosphere. The draped nature of the IMF about Mars, combined with the near‐perpendicular propagation of these waves across the magnetic field, act to channel these waves into the nightside ionosphere, where they are observed in their non‐linear steepened form. Coincident‐in‐time ion observations show that the light (H+) and heavy (O+, O2+, CO2+) planetary ion distribution functions possess significant suprathermal energetic tails, arising from wave‐particle interactions with the steepened waves. The short gyro period and small gyro radius of the protons, relative to the steepened waves, results in proton heating via adiabatic compression. In contrast, the long gyro period of the heavy ions relative to the wave frequency leads to nonadiabatic heating via wave‐trapping processes. The light and heavy ion species are heated above escape energy by these waves, even down close to the exobase. A limited statistical study of 101 neighboring orbits found that similar wave events occurred on 28% of orbits analyzed, suggesting that such wave‐heating events may be important drivers of the Mars nightside ionospheric dynamics and energy budget. Our discussion includes placing our results in the context of solar wind energy transfer to the ionospheres of unmagnetized and magnetized bodies in general.
Numerical Considerations in the Simulation of Equatorial Spread F
Authors: Li Zezhong , Lei Jiuhou , Zhang Binzheng
Published: October 2021

The ionospheric irregularities known as equatorial spread F (ESF) have drawn great attention in decades due to their disruption of communications and navigation systems. ESF is generally attributed to Rayleigh–Taylor instability, but there are still many remaining issues about its formation and evolution. Numerical simulations have been widely used to study such a phenomenon due to the complex nonlinear evolution of ESF. A two‐dimensional ESF model was developed in this work and a series of experiments were conducted to study the effects of grid resolution and numerical diffusion on idealized ESF simulation. It was found that advection schemes with the total variation diminishing property are preferred for preventing spurious oscillations which occur near the steep density gradients in the ESF. On the other hand, schemes with low diffusion are also desirable in order to model complicated dynamic structures of the ESF. Moreover, numerical experiments suggest that some of the secondary instabilities in idealized ESF simulations, although with morphological similarities, are possibly initiated by numerical seeding, which may differ from the observed evolution of secondary ESF.
Geodetic Constraints on a 25‐year Magmatic Inflation Episode Near Three Sisters, Central Oregon
Authors: Lisowski Michael , McCaffrey Robert , Wicks Charles W. , Dzurisin Daniel
Published: October 2021

Crustal inflation near the Three Sisters volcanic center documented since the mid‐1990s has persisted for more than two decades. We update past analyses of the event through 2020 by simultaneously inverting InSAR interferograms, GPS time series, and leveling data for time‐dependent volcanic deformation source parameters. We explore several source models to estimate how the deformation rate varied through time and to identify parameters that can reproduce measured deformation. Our preferred model is a Mogi source 4.1 km below sea level (5.9 km below the surface) about 5 km west of the summit of South Sister. Inflation started in late 1995 or 1996; the rate increased rapidly during 1998–1999, and peaked in late 1999, resulting in maximum surface uplift of about 30 cm by mid‐2020. Since 2000, the inflation rate generally declined exponentially with a time constant of about 6 years. Two source inflation scenarios fit the data equally well. In the first, the crust surrounding the source is elastic and the net source‐volume increase, which we attribute to persistent magma input, has been about 49 × 106 m3. The second scenario adds a viscoelastic shell surrounding the Mogi source. In that case, an injection of about 21 × 106 m3 of magma prior to 2000, followed by continuing relaxation of the viscoelastic shell, can account for most of the observed surface deformation. In both scenarios, modeling reveals quasiperiodic increases in the inflation rate (pulses) with a recurrence interval of 3–4 years, both before and after 2000.
Seasonal Modulation of Submesoscale Kinetic Energy in the Upper Ocean of the Northeastern South China Sea
Authors: Zhang Jinchao , Zhang Zhiwei , Qiu Bo , Zhang Xincheng , Sasaki Hideharu , Zhao Wei , Tian Jiwei
Published: October 2021

Although submesoscale processes are revealed to have a strong seasonality in many regions of global ocean, their seasonal modulation in the northeastern South China Sea (NESCS) remains unexplored by observations. In this study, approaches to diagnose submesoscale kinetic energy (KE) and its conversion terms using data from a single mooring are proposed and validated. Based on these approaches, seasonal modulation of submesoscale KE in the NESCS is for the first time investigated using 8.7‐year‐long moored velocity and temperature data between August 2010 and April 2019. It is found that the monthly climatology of submesoscale KE shows an asymmetric annual cycle with a steep peak between December and February but a flat trough between April and October. The maximum and minimum of this annual cycle occur in January and May, respectively. Although the submesoscale KE rapidly decreases with depth, its seasonality is still evident at 300 m, which is far beneath the mixed layer. Statistical analysis suggests that the overall seasonality of submesoscale KE is shaped by mixed‐layer depth while its steep peak in winter is modulated by mesoscale strain rate. It therefore suggests that the combination of mixed‐layer instability and strain‐induced frontogenesis determines the detailed annual cycle of submesoscale KE. Energetics analysis demonstrates that submesoscales obtain their KE from the release of available potential energy but lose a small portion of its KE through inverse cascade. This submesoscale inverse KE cascade may play an important role in modulating the temporal variation of mesoscale KE in winter.
Biomass Burning Over the United States East Coast and Western North Atlantic Ocean: Implications for Clouds and Air Quality
Authors: Mardi Ali Hossein , Dadashazar Hossein , Painemal David , Shingler Taylor , Seaman Shane T. , Fenn Marta A. , Hostetler Chris A. , Sorooshian Armin
Published: October 2021

Biomass burning (BB) aerosol events were characterized over the U.S. East Coast and Bermuda over the western North Atlantic Ocean (WNAO) between 2005 and 2018 using a combination of ground‐based observations, satellite data, and model outputs. Days with BB influence in an atmospheric column (BB days) were identified using criteria biased toward larger fire events based on anomalously high AERONET aerosol optical depth (AOD) and MERRA‐2 black carbon (BC) column density. BB days are present year‐round with more in June–August (JJA) over the northern part of the East Coast, in contrast to more frequent events in March–May (MAM) over the southeast U.S. and Bermuda. BB source regions in MAM are southern Mexico and by the Yucatan, Central America, and the southeast U.S. JJA source regions are western parts of North America. Less than half of the BB days coincide with anomalously high PM2.5 levels in the surface layer, according to data from 14 IMPROVE sites over the East Coast. Profiles of aerosol extinction suggest that BB particles can be found in the boundary layer and into the upper troposphere with the potential to interact with clouds. Higher cloud drop number concentration and lower drop effective radius are observed during BB days. In addition, lower liquid water path is found during these days, especially when BB particles are present in the boundary layer. While patterns are suggestive of cloud‐BB aerosol interactions over the East Coast and the WNAO, additional studies are needed for confirmation.
Properties of Mesoscale Convective Systems Throughout Their Lifetimes Using IMERG, GPM, WWLLN, and a Simplified Tracking Algorithm
Authors: Hayden Lindsey , Liu Chuntao , Liu Nana
Published: October 2021

Mesoscale convective systems (MCSs) occur frequently over the tropics and mid‐latitudes and have a large impact on the local precipitation amounts as well as large‐scale circulation through their modulation of the vertical diabatic heating profile. To fully understand and quantify these effects, MCSs must be studied throughout their lifetimes at both mid‐ and tropical latitudes, over both land and ocean. This can be accomplished by tracking the storm using a global scale data set of precipitation and using this information to composite collocated active sensor measurements to produce a detailed analysis of storm properties along the lifetime of the MCS. To do this, we utilize precipitation features (PFs) produced using observations from the Global Precipitation Measurement (GPM) mission's core satellite and from Integrated Multi‐satellitE Retrievals for GPM data by grouping contiguous raining pixels in both data sets. We propose a simplified tracking algorithm to track systems throughout their lifetimes. Lightning data from the World Wide Lightning Location Network are collocated to these tracks along with GPM PFs. These are then composited relative to the time step along the track that has the greatest number of lightning flashes, which is used as a proxy for MCSs with lightning reaching the maximum convective intensity. We then examine various radar variables for tropical and mid‐latitude systems of varying lifetimes over both land and ocean in order to determine the differences and similarities between these types of systems.
Aerosol Populations, Processes, and Ages in Bulk Deposition: Insights From a 9‐Year Study of 7Be, 210Pb, Sulfate, and Major/Trace Elements
Authors: Landis Joshua D. , Feng Xiahong , Kaste James M. , Renshaw Carl E.
Published: October 2021

We report fallout radionuclide (FRN) and major/trace element (MTE) contributions to bulk atmospheric deposition in Hanover, NH, USA (43.7022°N, 72.2896°W). Deposition of 7Be, 210Pb, and SO4 covary [R2 > 0.4, n = 461] but are discriminated by production sources, depositional mechanisms, meteorological controls, MTE associations, and seasonal biases. 7Be is dominated by rainout (78% of total deposition), recharged by long‐range transport (+23% over mean, o.m.), influenced by stratosphere‐troposphere exchange (+9% o.m.), and solar activity (−2% per doubling of sunspot count). Correlation with particulate nitrogen (+9% per doubling of N) indicates 7Be affinity for biogenic aerosols. 210Pb is dominated by dry + washout deposition (54% of total) and convective storms (+107% o.m), depleted in marine moisture sources (−133% o.m.), correlated with S (+9% per doubling of S), and biased to autumn with Mn, Hg, and V (+7% o.m.). Coincident long‐term declines in S and 210Pb (−14%, −4% per year) suggest co‐scavenging by PbSO4. 7Be:210Pb ratios increase asymptotically with precipitation through the dry‐washout‐rainout transition and recharge of 7Be. At the global scale, 7Be:210Pb increases with precipitation for North American/European sites due to recharge of 7Be in midlatitude storm belts [R2 = 0.64, n = 31]. Conversely, 7Be:210Pb is independent of precipitation for Southeast/East Asian sites where 7Be recharge is low [R2 = 0.01, n = 40]. Globally, 7Be:210Pb ratios in dry deposition reflect resuspended aerosols with mean age of ca. 200 days, contributing <5% of 210Pb deposition. Different aerosol populations contributing to FRN deposition across spatial and temporal scales should emerge as a focus in terrestrial 7Be, 210Pb, and 10Be tracer applications.
Evolving CO2 Rather Than SST Leads to a Factor of Ten Decrease in GCM Convergence Time
Authors: Zhang Yixiao , Bloch‐Johnson Jonah , Romps David M. , Abbot Dorian S.
Published: October 2021

The high computational cost of Global Climate Models (GCMs) is a problem that limits their use in many areas. Recently an inverse climate modeling (InvCM) method, which fixes the global mean sea surface temperature (SST) and evolves the mixing ratio to equilibrate climate, has been implemented in a cloud‐resolving model. In this article, we apply InvCM to ExoCAM GCM aquaplanet simulations, allowing the SST pattern to evolve while maintaining a fixed global‐mean SST. We find that InvCM produces the same climate as normal slab‐ocean simulations but converges an order of magnitude faster. We then use InvCM to calculate the equilibrium for SSTs ranging from 290 to 340 K at 1 K intervals and reproduce the large increase in climate sensitivity at an SST of about 315 K at much higher temperature resolution. The speedup provided by InvCM could be used to equilibrate GCMs at higher spatial resolution or to perform broader parameter space exploration in order to gain new insight into the climate system. Additionally, InvCM could be used to find unstable and hidden climate states, and to find climate states close to bifurcations such as the runaway greenhouse transition.
Impact of a New Cloud Microphysics Parameterization on the Simulations of Mesoscale Convective Systems in E3SM
Authors: Wang Jingyu , Fan Jiwen , Feng Zhe , Zhang Kai , Roesler Erika , Hillman Benjamin , Shpund Jacob , Lin Wuyin , Xie Shaocheng
Published: October 2021

Mesoscale convective systems (MCSs) are one of the most climatically significant forms of convection because of their large role in water and energy cycles. The mesoscale features associated with MCS are difficult to represent in climate models because the relevant dynamics and physics are absent or poorly represented with coarse model resolution (∼100 km). Using a regionally refined model (RRM) with 0.25° grid spacing embedded in the Energy Exascale Earth System Model (E3SM), we explore the impact of cloud microphysics parameterizations on the simulation of precipitation, particularly MCS precipitation over the contiguous United States. The Predicted Particle Properties (P3) cloud microphysics scheme has been modified and implemented into E3SM to overcome the limitations of the default Morrison and Gettelman (MG2) scheme in which rimed precipitating ice particles (graupel/hail) are absent and frozen particles are artificially partitioned into cloud ice and snow. We show that P3 improves the simulation of precipitation statistics including frequency distribution compared with MG2 with a limited effect on the diurnal cycle. P3 predicts higher hourly rain rates, resulting in 20% more MCSs and a higher total MCS precipitation (4.4%) compared to MG2, agreeing better with observations. The improvements with P3 mainly result from improved representations of ice microphysics, which not only produces higher rain rates through melting but also leads to a stronger large‐scale ascending motion by releasing more latent heating. This study suggests that improving microphysics parameterization is important for simulating MCS precipitation as future climate model resolutions continue to increase.
An Improved Parameterization of Wind‐Driven Turbulent Vertical Mixing Based on an Eddy‐Resolving Climate Model
Authors: Yuan Man , Song Zhuo , Li Zhuoran , Jing Zhao , Chang Ping , Sun Bingrong , Wang Hong , Liu Xin , Zhou Shenghui , Wu Lixin
Published: October 2021

Turbulent vertical mixing in the stratified ocean interior has a huge impact on global ocean circulations and the climate system. Although parameterizations of vertical mixing furnished by internal tides have been built into state‐of‐the‐art coupled global climate models (CGCMs), efforts in parameterizing wind‐driven vertical mixing in CGCMs are still limited. In this study, we apply a modified finescale parameterization (MFP) to an eddy‐resolving Community Earth System Model (CESM) to represent the wind's contribution to vertical mixing in the stratified ocean interior. The spatial pattern of the MFP‐parameterized wind‐driven vertical mixing in the thermocline agrees with the observation derived from the finestructure measurements of Argo floats, reproducing the enhanced values in the Kuroshio, Gulf Stream extensions, and the Southern Ocean where the winds inject great amount of energy into the internal wave field. The MFP also captures the observed seasonal variation of wind‐driven vertical mixing in the thermocline of these regions that exhibits enhancement and weakening in winter and summer, respectively. Application of the MFP to a non‐eddy‐resolving CESM fails to reproduce the observed wind‐driven vertical mixing. Specifically, the magnitude of parameterized wind‐driven vertical mixing in the thermocline of Kuroshio, Gulf Stream extensions, and the Southern Ocean is systemically smaller than those in the observation and eddy‐resolving CESM; so is the case for the amplitude of seasonal cycle. The results highlight the benefit of eddy‐resolving CESM compared to its standard‐resolution counterpart in parameterizing the wind‐driven vertical mixing and provide insight into developing parameterizations for wind‐driven vertical mixing in eddy‐resolving CGCMs.
Early Paleocene Paleoceanography and Export Productivity in the Chicxulub Crater
Authors: Lowery Christopher M. , Jones Heather L. , Bralower Timothy J. , Cruz Ligia Perez , Gebhardt Catalina , Whalen Michael T. , Chenot Elise , Smit Jan , Phillips Marcie Purkey , Choumiline Konstantin , Arenillas Ignacio , Arz Jose A. , Garcia Fabien , Ferrand Myriam , Gulick Sean P. S. ,   Expedition 364 Science Party
Published: October 2021

The Chicxulub impact caused a crash in productivity in the world's oceans which contributed to the extinction of ∼75% of marine species. In the immediate aftermath of the extinction, export productivity was locally highly variable, with some sites, including the Chicxulub crater, recording elevated export production. The long‐term transition back to more stable export productivity regimes has been poorly documented. Here, we present elemental abundances, foraminifer and calcareous nannoplankton assemblage counts, total organic carbon, and bulk carbonate carbon isotope data from the Chicxulub crater to reconstruct changes in export productivity during the first 3 Myr of the Paleocene. We show that export production was elevated for the first 320 kyr of the Paleocene, declined from 320 kyr to 1.2 Myr, and then remained low thereafter. A key interval in this long decline occurred 900 kyr to 1.2 Myr post impact, as calcareous nannoplankton assemblages began to diversify. This interval is associated with fluctuations in water column stratification and terrigenous flux, but these variables are uncorrelated to export productivity. Instead, we postulate that the turnover in the phytoplankton community from a post‐extinction assemblage dominated by picoplankton (which promoted nutrient recycling in the euphotic zone) to a Paleocene pelagic community dominated by relatively larger primary producers like calcareous nannoplankton (which more efficiently removed nutrients from surface waters, leading to oligotrophy) is responsible for the decline in export production in the southern Gulf of Mexico.
Productivity and Dissolved Oxygen Controls on the Southern Ocean Deep‐Sea Benthos During the Antarctic Cold Reversal
Authors: Stewart Joseph A. , Li Tao , Spooner Peter T. , Burke Andrea , Chen Tianyu , Roberts Jenny , Rae James W. B. , Peck Victoria , Kender Sev , Liu Qian , Robinson Laura F.
Published: October 2021

The Antarctic Cold Reversal (ACR; 14.7 to 13 thousand years ago; ka) phase of the last deglaciation saw a pause in the rise of atmospheric CO2 and Antarctic temperature, that contrasted with warming in the North. A reexpansion of sea ice and a northward shift in the position of the westerly winds in the Southern Ocean are well‐documented, but the response of deep‐sea biota and the primary drivers of habitat viability remain unclear. Here, we present a new perspective on ecological changes in the deglacial Southern Ocean, including multifaunal benthic assemblage (foraminifera and cold‐water corals) and coral geochemical data (Ba/Ca and δ11B) from the Drake Passage. Our records show that, during the ACR, peak abundances of thick‐walled benthic foraminifera Uvigerina bifurcata and corals are observed at shallow depths in the sub‐Antarctic (∼300 m), while coral populations at greater depths and further south diminished. Our ecological and geochemical data indicate that habitat shifts were dictated by (a) a northward migration of food supply (primary production) into the sub‐Antarctic Zone and (b) poorly oxygenated seawater at depth during this Antarctic cooling interval.