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Variable wind speeds over the ocean can have a significant impact on the formation mechanism and physical-chemical properties of sea spray aerosols (SSA), which in turn influence their climate-relevant impacts. Herein, for the first time, we investigate the effects of wind speed on size-dependent morphology and composition of individual nascent SSA generated from wind-wave interactions of natural seawater within a wind-wave channel as a function of size and their particle-to-particle variability. Filter-based thermal optical analysis, atomic force microscopy (AFM), AFM infrared spectroscopy (AFM-IR), and scanning electron microscopy (SEM) were employed in this regard. This study focuses on SSA with sizes within 0.04-1.8 μm generated at two wind speeds: 10 m/s, representing a wind lull scenario over the ocean, and 19 m/s, indicative of the wind speeds encountered in stormy conditions. Filter-based measurements revealed a reduction of the organic mass fraction as the wind speed increases. AFM imaging at 20% relative humidity of individual SSA identified six main morphologies: prism-like, rounded, core-shell, rod, rod inclusion core-shell, and aggregates. At 10 m/s, most SSA were rounded, while at 19 m/s, core-shells became predominant. Based on AFM-IR, rounded SSA at both wind speeds had similar composition, mainly composed of aliphatic and oxygenated species, whereas the shells of core-shells displayed more oxygenated organics at 19 m/s and more aliphatic organics at 10 m/s. Collectively, our observations can be attributed to the disruption of the sea surface microlayer film structure at higher wind speeds. The findings reveal a significant impact of wind speed on morphology and composition of SSA, which should be accounted for accurate assessment of their climate effects.

Sanjay K Agarwal,1 Michael Stokes,2 Tiffany Kung,3 Rong Tilney,2 Cassandra Lickert3 1UC San Diego, La Jolla, CA, USA; 2Evidera, St. Laurent, Quebec, Canada; 3Myovant Sciences, Inc (now known as Sumitomo Pharma America, Inc), Marlborough, MA, USACorrespondence: Cassandra Lickert, Sumitomo Pharma America, Inc, 4 Waterford Drive, Marlborough, MA, 01752, USA, Tel +1 (708) 214-1007, Email Cassandra.lickert@us.sumitomo-pharma.comIntroduction: This retrospective database claims analysis describes the clinical characteristics and treatment patterns of commercially insured United States women with uterine fibroids (UF) and heavy menstrual bleeding (HMB).Methods: Women age 18– 55 years with an incident UF diagnosis (index date) between 1/1/2012 and 12/31/2019 and ≥ 1 claim for HMB (UF-HMB), were identified from the Optum® Clinformatics® database. Outcomes included clinical characteristics, pharmacologic therapy use, and surgeries/procedures. Regression models were used to identify factors associated with time to post-diagnosis hormonal therapy and hysterectomy.Results: A total of 85,428 women had UF-HMB (mean [SD] age, 43.7 [6.4] years). The median follow-up was 3.2 years. After HMB, the most common symptoms were pelvic pressure/pain (27.6%) and backache (17.5%). Within 6 months of UF diagnosis, 40.2% of patients had received only pharmacologic therapy; 25.5% had received no treatment; 24.3% had a hysterectomy, and 10.0% had other procedures. By the end of follow-up, 50.0% had received a hysterectomy. Multiple factors were predictive of a higher likelihood of receiving hormonal therapy (geographic region, infertility, pre-index pregnancy) or hysterectomy (older age, prior hormonal treatment, specific bulk symptoms, White race).Conclusion: Within 6 months of UF diagnosis, fewer than one-half of women with UF-HMB had received hormonal therapy, one-quarter received no treatment, and one-quarter had received a hysterectomy or another gynecologic procedure. Patients who received a hysterectomy were more likely to be older, White, and to have bulk symptoms.Keywords: uterine fibroids, leiomyoma, heavy menstrual bleeding, menorrhagia

On Conch Reef, Florida Keys, USA we examined the effects of reef hydrography and topography on the patterns of stable isotope values (δ18O and δ13C) in the benthic green alga, Halimeda tuna. During the summer, benthic temperatures show high-frequency fluctuations (2 to 8 °C) associated with internal waves that advected cool, nutrient-rich water across the reef. The interaction between local water flow and reef morphology resulted in a highly heterogenous physical environment even within isobaths that likely influenced the growth regime of H. tuna. Variability in H. tuna isotopic values even among closely located individuals suggest biological responses to the observed environmental heterogeneity. Although isotopic composition of reef carbonate material can be used to reconstruct past temperatures (T(°C) = 14.2-3.6 (δ18OHalimeda - δ18Oseawater); r2 = 0.92), comparing the temperatures measured across the reef with that predicted by an isotopic thermometer suggests complex interactions between the environment and Halimeda carbonate formation at temporal and spatial scales not normally considered in mixed sediment samples. The divergence in estimated range between measured and predicted temperatures demonstrates the existence of species- and location-specific isotopic relationships with physical and environmental factors that should be considered in contemporary as well as ancient reef settings.

The oceans represent a significant global source of atmospheric aerosols. Sea spray aerosol (SSA) particles comprise sea salts and organic species in varying proportions. In addition to size, the overall composition of SSA particles determines how effectively they can form cloud droplets and ice crystals. Thus, understanding the factors controlling SSA composition is critical to predicting aerosol impacts on clouds and climate. It is often assumed that submicrometer SSAs are mainly formed by film drops produced from bursting bubble-cap films, which become enriched with hydrophobic organic species contained within the sea surface microlayer. In contrast, jet drops formed from the base of bursting bubbles are postulated to mainly produce larger supermicrometer particles from bulk seawater, which comprises largely salts and water-soluble organic species. However, here we demonstrate that jet drops produce up to 43% of total submicrometer SSA number concentrations, and that the fraction of SSA produced by jet drops can be modulated by marine biological activity. We show that the chemical composition, organic volume fraction, and ice nucleating ability of submicrometer particles from jet drops differ from those formed from film drops. Thus, the chemical composition of a substantial fraction of submicrometer particles will not be controlled by the composition of the sea surface microlayer, a major assumption in previous studies. This finding has significant ramifications for understanding the factors controlling the mixing state of submicrometer SSA particles and must be taken into consideration when predicting SSA impacts on clouds and climate.

Ice nucleating particles (INPs) are vital for ice initiation in, and precipitation from, mixed-phase clouds. A source of INPs from oceans within sea spray aerosol (SSA) emissions has been suggested in previous studies but remained unconfirmed. Here, we show that INPs are emitted using real wave breaking in a laboratory flume to produce SSA. The number concentrations of INPs from laboratory-generated SSA, when normalized to typical total aerosol number concentrations in the marine boundary layer, agree well with measurements from diverse regions over the oceans. Data in the present study are also in accord with previously published INP measurements made over remote ocean regions. INP number concentrations active within liquid water droplets increase exponentially in number with a decrease in temperature below 0 °C, averaging an order of magnitude increase per 5 °C interval. The plausibility of a strong increase in SSA INP emissions in association with phytoplankton blooms is also shown in laboratory simulations. Nevertheless, INP number concentrations, or active site densities approximated using "dry" geometric SSA surface areas, are a few orders of magnitude lower than corresponding concentrations or site densities in the surface boundary layer over continental regions. These findings have important implications for cloud radiative forcing and precipitation within low-level and midlevel marine clouds unaffected by continental INP sources, such as may occur over the Southern Ocean.

The composition and surface properties of atmospheric aerosol particles largely control their impact on climate by affecting their ability to uptake water, react heterogeneously, and nucleate ice in clouds. However, in the vacuum of a conventional electron microscope, the native surface and internal structure often undergo physicochemical rearrangement resulting in surfaces that are quite different from their atmospheric configurations. Herein, we report the development of cryogenic transmission electron microscopy where laboratory generated sea spray aerosol particles are flash frozen in their native state with iterative and controlled thermal and/or pressure exposures and then probed by electron microscopy. This unique approach allows for the detection of not only mixed salts, but also soft materials including whole hydrated bacteria, diatoms, virus particles, marine vesicles, as well as gel networks within hydrated salt droplets-all of which will have distinct biological, chemical, and physical processes. We anticipate this method will open up a new avenue of analysis for aerosol particles, not only for ocean-derived aerosols, but for those produced from other sources where there is interest in the transfer of organic or biological species from the biosphere to the atmosphere.

Sufficiently energetic breaking ocean waves produce distinctive visible foam signatures on the water surface called whitecaps. The mixture of surface whitecap foam cells, and sub‐surface bubbles, results in the broad‐band scattering of light that allow whitecaps to be measured with optical cameras. In this paper the temporal evolution of whitecap foam area from laboratory and oceanic breaking waves is compared. When appropriately scaled, the foam area time series for both laboratory and oceanic breaking waves follow similar trends, despite occurring in vastly different settings. Distinct similarities of the signature of foam stabilization due to the presence of surfactants in the controlled laboratory experiments are also found in the field suggesting foam stabilization may be a means to remotely sense the presence/absence or concentration of surfactants in the ocean. In addition, probability density distributions of key whitecap variables such as foam area growth and decay timescales and maximum foam area are compared between laboratory and oceanic whitecaps. The oceanic whitecaps are much larger in scale than the laboratory breaking waves, whereas the whitecap growth and decay timescales are similar in magnitude, the latter suggesting that the depths to which bubbles are injected during active air entrainment in the field are relatively shallow. The aggregated whitecap statistics are used to estimate the energy dissipation of individual whitecaps in a novel manner. Plain Language Summary: The breaking of ocean waves is a key process controlling the evolution of oceanic sea states and the exchange of energy, momentum and material across the ocean‐atmosphere interface. Despite their importance, little is known about the energetics of individual breaking waves in the ocean because of the difficulty in precisely measuring the complicated fluid motions they produce. However, when they are sufficiently energetic, they entrain air and appear as white foam patches on the water surface, and are called whitecaps. This means that their occurrence and scale can be measured using relatively affordable optical cameras. In this paper we show that the patterns of foam evolution in laboratory breaking waves and oceanic whitecaps are remarkably similar giving us confidence that what we learn from laboratory experiments can be confidently applied to real oceanic whitecaps. Building on this, we show what parts of the whitecap foam area evolution can be used to learn more about ocean chemistry and breaking wave energetics. We hope that further development of the principles outlined in this paper can transform how oceanic whitecaps are observed in the ocean and ultimately lead to a better understanding of ocean waves and their evolution. Key Points: Foam area evolution from laboratory breaking waves and oceanic whitecaps is comparedSelf‐similar behavior in foam area evolution is evident in laboratory and field data setsEnergy dissipated by individual breaking waves can be estimated from foam area time history [ABSTRACT FROM AUTHOR]

This paper presents an apparatus and associated methods for making direct in situ measurements of the ice–water boundary of small pieces of floating glacier ice. The method involves approaching ice pieces in a small boat and attaching a frame with instruments on it to them using ice screws. These types of measurements provide an opportunity to study small-scale processes at the ice–water interface which control heat flux across the boundary. Recent studies have suggested that current parameterizations of these processes may be performing poorly. Improving understanding of these processes may allow for more accurate theoretical and model descriptions of submarine melting. [ABSTRACT FROM AUTHOR]

Migraine is a disabling neurological disease that affects 14.7 % of Europeans. Studies evaluating the economic impact of migraine are complex to conduct adequately and with time become outdated as healthcare systems evolve. This study sought to quantify an