Winter Months Research Articles

Availability of fresh water in cold climate regions

Challenges related to the availability of fresh water in cold climate regions are discussed with emphasis on possible degradation of the quality of drinking water. The permafrost in this region has been consistent in making sure there is little drainage in the ground. This is important, as fresh water is mainly supplied through melting water from snow and ice in the many winter months. Climate change and warmer weather plays a role in heating up the permafrost and increasing the rate of the melting snow. This has an impact on both the amount of water and potentially the drinking quality. In certain cold region areas, fresh water sources are located not far from the shore. With increased shorline erosion due to warming climate, the fresh water supply is in danger of being contaminated by salt water during large storm events. Furthermore, human activities such as road transport and sewage contamination do also have a significant impact on the water’s quality. A bowtie diagram will be used to illustrate the different risk factors and suggestions on how to maintain the quality of fresh water supplies in cold climate areas. The primary focus areas will be Isdammen, near Longyearbyen on Svalbard and Utqiagvik (formerly Barrow), Alaska.

Ecología de una taxocenosis de Calliphoridae del área platense (Provincia de Buenos Aires) (Insecta, Diptera)

This paper constitutes the first approach to the knowledge of the ecology of Calliphoridae from Argentina. The selected stüdied area is a rural one located at 34°55’S and 58° W in the suburbs of Villa Elisa, Province of Buenos Aires. Samples were taken hourly from 10.15 am to 4.15 pm, every month from November 1985 to October 1986. Specimens were captured with entomological net while lying on the bait composed by cow meat. The sampling program included shaded and unshaded sites. Air temperature was recorded every hour. Results showed a remarkable heliophily for some of the recorded species. Chrysomya albiceps, Phaenicia sericata, Phaenicia purpurescens and Cochlipmyia macellaria were codominants during spring and summer, while Calliphora vicina and Calliphora nigribasis were so along the winter months. Chrysomya megacephala, Cochliomyia hominivorax,. Compsomyiops fulvierura, Paralucilia fulvinota, Phaenicia eximia, and Sarconesia chlorogaster were poorly represented for most o f the sampling dates. Sex ratio was female biased for the majority of the studied species.

Classification of Aerosols Types Over Iraq, using MODIS Date

The optical properties of aerosols are derived from Moderate Resolution Imaging Spectroradiometer (MODIS) observations for the period 2003–2021 at seventeen regions in Iraq, which were used to determine the different types of aerosols using threshold values based on Aerosols Optical Depth (AOD) and Angstrom Exponent (AE), seasonal aerosol classification was performed. This approach was verified and used in the detection process. Six aerosols categories: maritime, dust, mixture, urban, dust desert, and biomass burning were examined in this study. The result indicates that dust is most frequently detected in the summer and spring seasons, while the maritime type is most common in the winter and autumn, with wide variability in mixture type. The relative contribution during the winter months revealed a clear predominance of Maritime-type aerosols in the northern part of Iraq. Maximum contributions recorded in Erbil (93%), and Sulaymaniyah (90%). The maximum relative contributions of dust are found in the range of 71%–77% over Qaim and Haditha, while the southern regions of Iraq have a percentage ranging from 54%–65% in the summer season. The results of the monthly classification of aerosol type indicate that dust type are overhead maritime aerosols between March and September in the west, northwest, and south regions of Iraq. The highest contribution of desert dust was recorded in Basra, 60% during July and August. The maximum urban type was recorded at 50% in Baghdad in June. Biomass-burning type contribution was very little.

PP10 Preventing The Winter Quadruple Threat: The Value Of Hospital Bed Capacity Freed Up By Vaccination

IntroductionHospitals in England experience extremely high levels of bed occupancy in the winter. In these circumstances, vaccine-preventable hospitalizations due to seasonal respiratory infections, have a high cost because of the missed opportunity to treat other patients on the waiting list.This study sought to generate evidence on the hospitalizations that vaccines for older adults against seasonal influenza (flu), pneumococcal disease (PD), respiratory syncytial virus (RSV) and COVID-19 may prevent during the winter season (October-March) in England. The monetary value of the vaccine-preventable hospitalizations was estimated using a conventional reference costing method and a novel opportunity costing approach.MethodsBased on retrospective analysis of Hospital Episode Statistics data on hospitalizations in England, and efficacy and observed coverage rates per vaccination program, we estimated the number of bed-days that current vaccines against flu, PD and COVID-19, and a hypothetical RSV vaccine, could free up by preventing hospitalizations in the winter among older adults. We valued the freed-up bed-days (1) as the cost of prevented hospitalizations (reference cost); (2) as the Net Monetary Benefit (NMB) generated by alternative uses of the freed-up bed-days. The opportunity cost of vaccines-preventable hospitalizations is (2) when they would be an optimal use of beds or (1)+(2) when they would be a suboptimal use.ResultsIn the winter months, vaccination programs targeting flu, PD and RSV for older adults could collectively prevent 72,813 bed days and save over £45million (USD56 million) in hospitalization costs. The COVID-19 vaccine could prevent over 2 billion bed days and save GBP1.3 billion. Importantly, the value of hospital beds freed up by vaccination is likely to be 1.1–2 times larger (£48–£93 million [USD60-116 million] for flu, PD and RSV; £1.4–£2.8 billion [USD1.8-3.5 billion] for COVID-19) when quantified in opportunity cost terms. Scenario analysis replacing the current vaccine used in the adult PD program with the newly licensed pneumococcal conjugate 20-valent vaccine (PCV20), would increase the impact of each modelled outcome for this program by approximately 38 times.ConclusionsVaccines for flu, PD, RSV and COVID-19 could prevent a significant number of hospitalizations in the winter. The value of the associated freed-up bed capacity is likely to be underestimated by conventional reference costing methods.

Evaluating the effectiveness of the Ministry of Health restriction policy on seasonal antibiotic consumption trends in Saudi Arabia, 2016–2020

Background: Understanding antibiotic consumption patterns over time is essential to optimize prescribing practices and minimizing antimicrobial resistance. This study aimed to determine whether the antibiotics restriction policy launched by the Saudi Ministry of Health in April 2018 has impacted antibiotic use by assessing changes and seasonal variations following policy enforcement.Methods: Quarterly sales data of J01 antibacterial for systemic use in standard units were obtained from the IQVIA-MIDAS database, spanning from the first quarter of 2016 to the last quarter of 2020. Antibiotics consumption was measured in defined daily doses per 1,000 inhabitant per day- in a quarter (DDDdq). A comparative analysis of antibiotic consumption pre- and post-policy periods introduction was conducted by computing the average consumption values for each period. Statistical comparison of the mean differences between the two periods were then made using independent samples t-test, Mann-Whitney U Test where needed. Time series analysis was employed to estimate the projected antibiotic consumption in the post-policy period if the restriction policy had not been implemented, which was then compared to actual consumption values to evaluate the effectiveness of the restriction policy.Results: During the pre-policy, there were seasonal trends of the total and oral antibiotic consumption through quarters, with higher consumption observed in the first and fourth quarters. In contrast, parenteral antibiotic consumption did not appear to follow a clear seasonal pattern. Following the restriction policy, there was a significant reduction in total and oral antibiotic use, with mean reductions of −96.9 DDDdq (p-value = 0.002) and −98 DDDdq (p-value = 0.002), respectively. Conversely, a significant increase in parenteral antibiotic consumption was observed with a mean increase of +1.4 DDDdq (p-value < 0.0001). The comparison between the forecasted and actual models showed that the actual antibiotics consumption for total, oral, and parenteral were lower than the corresponding forecasted values by 30%, 31%, and 34%, respectively.Conclusion: Overall, our analysis of antibiotics consumption from 2016 to 2020 displays great success for the policy implemented by the Saudi Ministry of Health in significantly reducing the total and oral use of antibiotics. However, future studies are needed to explore the increased consumption of the parenteral antibiotics as well as the persistent high consumption patterns during the fall and winter months even after the implementation of the restriction policy.

Epidemiological study of animal bite cases attending a tertiary care hospital in Tripura: North-East India

Background: This research article presents an epidemiological study in Tripura, North-east India, investigating animal bite cases at a tertiary care hospital. Animal bites pose significant public health concerns, including potential zoonotic disease transmission. The study aims to assess animal bite incidence, envenoming, and treatment-seeking behaviours among victims. Data from individuals over one year old will reveal the burden of animal bites on healthcare facilities, guiding effective prevention and management strategies for this pressing health issue. Methods: A cross-sectional study at AGMC and GBP Hospital, Tripura, assessed animal bite patterns referred to the ARV centre (2018–2021). Included animal-related bites and excluded incomplete data. Collected age, gender, socio-economic status, biting animal, and bite category. Staff ensured nationwide surveillance. Categorised subjects by age. Results: The cross-sectional study investigated animal bite patterns at AGMC and GBP Hospital, Agartala, Tripura, from 2018 to 2021. Analysis revealed male adults (20-39 years, 41.7%) were most affected, predominantly by dogs (57.58%). The APL category showed the highest frequency (70.79%). Missing category bites decreased, while third category bites increased over time. The winter months had higher frequencies of animal bites. Continued surveillance and targeted interventions are vital for effective prevention. Conclusions: This study highlights male adults (20–39 years old) as being most affected, predominantly by dog bites. The APL category showed higher susceptibility. Continued surveillance and targeted interventions are crucial for effective prevention.

Functional redundancy of seasonal vitamin B12 biosynthesis pathways in coastal marine microbial communities.

Vitamin B12 (cobalamin) is a major cofactor required by most marine microbes, but only produced by a few prokaryotes in the ocean, which is globally B12 -depleted. Despite the ecological importance of B12 , the seasonality of B12 metabolisms and the organisms involved in its synthesis in the ocean remain poorly known. Here we use metagenomics to assess the monthly dynamics of B12 -related pathways and the functional diversity of associated microbial communities in the coastal NW Mediterranean Sea over 7 years. We show that genes related to potential B12 metabolisms were characterized by an annual succession of different organisms carrying distinct production pathways. During the most productive winter months, archaea (Nitrosopumilus and Nitrosopelagicus) were the main contributors to B12 synthesis potential through the anaerobic pathway (cbi genes). In turn, Alphaproteobacteria (HIMB11, UBA8309, Puniceispirillum) contributed to B12 synthesis potential in spring and summer through the aerobic pathway (cob genes). Cyanobacteria could produce pseudo-cobalamin from spring to autumn. Finally, we show that during years with environmental perturbations, the organisms usually carrying B12 synthesis genes were replaced by others having the same gene, thus maintaining the potential for B12 production. Such ecological insurance could contribute to the long-term functional resilience of marine microbial communities exposed to contrasting inter-annual environmental conditions.

Enabling coordination in energy communities: A Digital Twin model

Starting from the EU vision for Energy Communities (EC), our purpose is to support them by proposing a Digital Twin (DT) that includes a bi-level optimization model to deliver coordination, economic, social, and environmental benefits to its members that can be quantified as Key Performance Indicators (KPI). The diversity of EC members from the size and interest perspectives leads us to consider a bi-level optimization model. It offers support to individual consumers/prosumers (first level) and coordination for EC (second level). This model is embedded into a DT that replicates the EC and the operation of individual entities such as consumers/prosumers and public assets. The DT is created as an automatic assistant with two components: iEMS – as a member's assistant and eEMS – as an EC assistant. These components optimize the schedule, generate bids for the Local Electricity Market (LEM) and control the flexible appliances of the participants to deal with deficits and surpluses. The DT receives input from EC members, LEM, metering system and improves the operation of the EC in a two-way continuous exchange data flow. Furthermore, it is a reliable framework to test and improve models, regulations and policies in emergent EC as DT provides alternatives regarding its functionalities: optimization, market operation, setting the clearing price, settlement, value sharing for distributing benefits, etc. It can be extended to support grid operators to design tariffs, testing regulation and offer additional energy services. The proposed DT model is tested within an EC case study, both on a seasonal and an annual basis. The average trading index on LEM is 0.6 during the summer and 0.3 during the winter months, while the Degree of Local Sufficiency (DLS) for the EC is 0.45 in summer and 0.28 in winter. Moreover, the proposed LFM model reduces the exchanges with the main grid by an average of 45 kW in summer, that represents almost 15% of the average exchange at peak hours.

Enhancing Propagation of Orostachys spp. Offsets through Exogenous GA3 Application

Orostachys spp., considered economically important succulent plants for both the medicinal and ornamental plant industries, are known to exhibit slow growth in their offsets during the long, cold winter months. Due to the slow growth, this study investigated the application of gibberellic acid (GA3) and determined the optimal GA3 concentration (control, 200 mg·L−1, 400 mg·L−1, and 600 mg·L−1) for promoting the propagation of three Orostachys species (i.e., O. fimbriata, O. japonica, and O. minuta), as well as its impact on their growth and development. According to our study findings, O. fimbrata and O. minuta influenced by GA3 exhibited higher survival rates (7–38%) and offset growth rates (3–87%) compared to the control. Similarly, its application resulted in significant shoot and root development, along with increased moisture content for the majority of the species. The results of this research demonstrate the potential and practical applications of using GA3 to increase the propagation and growth of Orostachys spp. during cold conditions for year-round propagation of these succulent plants, which could have ecological and horticultural significance for related species as well as other vegetatively propagated crops.

Vitamin D status in children with congenital melanocytic nevi.

Congenital melanocytic nevi (CMN) are rare, pigmented birthmarks that can predispose patients to melanoma of the central nervous system and skin. Data from non-CMN melanoma cohorts suggest that vitamin D levels may be connected to outcome, prompting this study of 25-hydroxyvitamin D levels in plasma samples from 40 children with CMN. While 27% were insufficient and 13% deficient, this was representative of European populations, and UK supplementation guidelines are already in place. Our data support routine vitamin D supplementation for all CMN patients during winter months, without routine serum measurement.

2308. Exploring the Seasonality of COVID-19 with Machine Learning: A Distinct Bimodal Pattern?

Abstract Background Respiratory viruses, such as influenza and RSV, occur annually during the winter season in temperate regions. It is essential to determine if SARS-CoV-2 exhibits seasonal patterns for public health planning and vaccination policies. Although winter spikes in COVID-19 cases have been observed, the higher transmissibility of SARS-CoV-2 suggests its seasonality may have a different pattern. Methods We plotted the time-series data on COVID-19, Influenza, and RSV from January 2020-February 2023 at Stanford Healthcare, to compare seasonal patterns. We then modeled predictions for COVID-19 cases in the United States for the next 913 days, using data from January 2020-February 2023. This data was split into a training set and a test set, then Facebook Prophet machine learning library was used to fit a model to the training set and generate forecasts for the test set and future time periods. Cross-validation of the model was performed by calculating the root mean squared error (RMSE) and mean absolute percentage error (MAPE). Results The time-series data of cases for Influenza, RSV, and COVID-19 were plotted from January 1, 2020, to February 28, 2023, revealing bimodal peaks for COVID-19 during the winter (December - February) and summer (July - September) months (Figure 1). This differed from the unimodal patterns observed for Influenza and RSV cases (Figures 2 and 3, respectively). The Prophet model for COVID-19 cases over the next 913 days in the United States demonstrated an additional peak during the summer months (Figure 4). However, other external factors that may influence seasonality, such as the stochastic development of new SARS-CoV-2 variants, weaning of immunity, and testing intensity were not modeled.Figure 1.COVID-19 time-series at Stanford Healthcare during January 2020–February 2023Time-series of COVID-19 cases demonstrates bimodal peaks during the winter (December - February) and summer (July - September) months.Figure 2.Influenza time-series at Stanford Healthcare during January 2020–February 2023Time-series of Influenza cases demonstrates one peak during the winter (December - February) months.Figure 3.RSV time-series at Stanford Healthcare during January 2020–February 2023Time-series of RSV cases demonstrates one peak during the winter (December - February) months. Conclusion COVID-19 may exhibit distinct bimodal seasonal patterns that are not observed for other respiratory viruses. Future public health interventions should consider the distinct seasonal patterns of COVID-19 when developing prevention and control strategies.Figure 4.Prophet Model forecasting COVID-19 peaks in the United States for the next 3 years Cross-validation results for the Prophet model's performance in predicting COVID-19 cases in the United States over a 5-day horizon. The model's RMSE was 110,342.81, indicating an average deviation from the actual values. The MAPE was 0.486, reflecting the model's average percentage error. The coverage was 0.35, indicating that the actual value fell within the 80% prediction interval of the model only 35% of the time, which may suggest limitations for longer-term forecasting. Disclosures All Authors: No reported disclosures

Drivers of Cloud Condensation Nuclei in the Eastern North Atlantic as Observed at the ARM Site

AbstractSeven years of data collected at the Atmospheric Radiation Measurement's Eastern North Atlantic (ENA) site are analyzed to understand the controls of Cloud Condensation Nuclei (CCN) concentrations in the region. Day‐night differences in the aerosol data as segregated by wind direction demonstrate the aerosol observations to be impacted by local emissions when the wind direction (wdir) is between 90° and 310° (measured clockwise from the North where air is coming from). Data collected during marine conditions (wdir <90° or wdir >310°) show the CCN concentrations to be higher in the summer months as compared to the winter months. CCN budget analysis revealed advection and precipitation scavenging being primarily responsible for modulating the CCN concentrations at the site on monthly timescales, with rain rates driving the precipitation scavenging term. High (greater than 75th percentile) and low (lower than 25th percentile) CCN events were identified for each month to characterize the sub‐monthly variability of CCN concentrations. Low CCN events had thicker clouds, stronger rain rates, and lower reanalysis reported free‐tropospheric aerosol pseudo number concentration at the ENA site as compared to the high CCN events. Analysis of satellite data of air‐parcels 48 hr prior to their arrival at the ENA site demonstrated the air parcels during low CCN events to encounter higher cloudiness, stronger rain rates, and higher cloud top heights as compared to the high CCN events. The results presented herein provide key constraints for model evaluation studies and climatological studies conducted at the ENA site.

Enhancing the Yield, Quality and Antioxidant Content of Lettuce through Innovative and Eco-Friendly Biofertilizer Practices in Hydroponics

Hydroponics is a contemporary agricultural system providing precise control over growing conditions, potentially enhancing productivity. Biofertilizers are environmentally friendly, next-generation fertilizers that augment product yield and quality in hydroponic cultivation. In this study, we investigated the effect of three bio-fertilizers in a hydroponic floating system, microalgae, plant growth-promoting rhizobacteria (PGPR) and arbuscular mycorrhizal fungi (AMF), combined with a 50% reduction in mineral fertilizer, on lettuce yield and quality parameters including antioxidants: vitamin C, total phenols and flavonoids. The treatments tested were: 100% mineral fertilizer (control 1), 50% mineral fertilizer (control 2), 50% mineral fertilizer with microalgae, 50% mineral fertilizer with PGPR and 50% mineral fertilizer with AMF. The research was conducted during the winter months within a controlled environment of a glasshouse in a Mediterranean climate. The PGPR comprised three distinct bacterial strains, while the AMF comprised nine different mycorrhizal species. The microalgae consisted of only a single species, Chlorella vulgaris. AMF inoculation occurred once during seed sowing, while the introduction of PGPR and microalgae occurred at 10-day intervals into the root medium. Our findings revealed that the treatment with PGPR resulted in the highest growth parameters, including the lettuce circumference, stem diameter and fresh leaf weight. The 100% mineral fertilizer and PGPR treatments also yielded the highest lettuce production. Meanwhile, the treatment with AMF showed the highest total phenol and flavonoid content, which was statistically similar to that of the PGPR treatment. Furthermore, the PGPR recorded the maximum range of essential nutrients, including nitrogen (N), potassium (K), iron (Fe), zinc (Zn) and copper (Cu). Thus, the inclusion of PGPR holds promise for optimizing the lettuce growth and nutrient content in hydroponic systems. In conclusion, PGPR has the potential to enhance nutrient availability in a floating hydroponic system, reducing the dependence on chemical fertilizers. This mitigates environmental pollution and fosters sustainable agriculture.

Epidemiology and emm types among group A streptococcal pharyngitis in Finland: a prospective laboratory-based study

PurposeStreptococcus pyogenes (mostly termed group A Streptococcus - GAS) is the most important bacterial causative of pharyngitis. However, epidemiology of GAS pharyngitis is not widely established. This study describes GAS pharyngitis cases and emm-type distribution in a prospective study covering over 2 years in two Hospital Districts in Finland.MethodsA prospective, systematic collection of GAS pharyngitis isolates was conducted between March 2018 and December 2020 in two large Hospital Districts in Finland. Patient characteristics (age, gender) were included if available. All GAS isolates collected were emm typed.ResultsAltogether 1320 GAS pharyngitis strains were collected, 904 in the Hospital District 1 (HD1) and 416 in Hospital District 2 (HD2). In HD1, age and gender data were available. Females were overrepresented (58% of all cases). In addition, the age and gender distributions were noted to be significantly different (p < 0.0001) with females having a more uniform distribution until age of 40. emm28 was common among the age group of 20–29-year-olds and emm89 in children under 10 years of age, respectively. In HD1, most of the isolates were collected during winter and autumn months. Significant differences by season in the frequency of emm12, emm89, emm75 and group of “others” were observed.ConclusionAge distribution among GAS pharyngitis cases was significantly different between genders (p < 0.0001). In addition, age group specific and seasonal variations in emm GAS types causing the disease were observed. These findings warrant further investigation, especially for understanding population-based spread of GAS even in more detail.

Indoor environment quality effects on occupant satisfaction and energy consumption: Empirical evidence from subtropical offices

This study examines the impact of indoor environment quality (IEQ) on occupant satisfaction and energy consumption in Australia’s subtropical office buildings. First, Kano’s model was applied to 201 office occupants' satisfaction surveys to understand the influence of each IEQ parameter on overall occupant satisfaction. Then, a quantitative relationship between monitored IEQ parameters and energy consumption in three office buildings was developed during summer, winter and transitional months. Using Kano’s model, IEQ parameters were classified into Basic Factors, Performance Factors, and Bonus Factors based on their impact on occupants’ overall satisfaction. Basic Factors include ‘acoustic environment’, ‘lighting environment’, ‘level of privacy’, and’office cleanliness’, which were deemed a prerequisite for occupant satisfaction. As Performance Factors, ‘thermal environment’, ‘indoor air quality’, ‘furnishing’, ‘available space’ and ‘personal control’ had proportional relationships with overall satisfaction. The only identified Bonus Factor positively impacting overall occupant satisfaction was ‘View from the windows’. In subtropical climates, the relationship between IEQ parameters and energy consumption reveals that artificial lighting is the most energy-intensive IEQ parameter. The findings also suggest that Australian building experts may have over-emphasised the role that achieving thermal comfort plays in the energy consumption of office buildings in Australia’s temperate climates.

Double-battery configuration method for electric bus operation in cold regions

Managing the energy supply of electric buses (EBs) is critical to balance operational reliability and cost reduction. However, ambient temperature significantly affects energy consumption, posing challenges in providing adequate energy supply, especially in cold regions. In this study, we propose a double-battery configuration approach for EBs operating in cold regions with substantial temperature variations between seasons. The method involves utilizing a higher-capacity battery during winter months and a lower-capacity battery for summer operations. To determine the optimal fleet size, battery capacities, and EB scheduling plans in both winter and summer seasons, we formulate an integer programming model, focusing on minimizing the fleet's average annual operating costs (OC) and carbon emissions (CE). The model is solved using the branch and bound method. A case study is conducted, examining EB routes in 11 cold cities. Results reveal that the double-battery configuration method effectively reduces the fleet's average annual OC and CE. Specifically, the reduction ratio range for OC is from 3.34% to 5.18%, while the reduction ratio for CE ranges from 4.06% to 5.16%.

A case of early breeding of Pied Avocet (&lt;i&gt;Recurvirostra avosetta&lt;/i&gt;)

On the 14th of April 2022, during a periodic bird monitoring activity in a wetland area located in the municipality of Mirandola (Moedna), Northern Italy, a breeding pair of Pied Avocets Recurvirostra avosetta, were recorded along with chicks aged approximately 2/3 days old. This is clearly a case of extremely early breeding seeing as, in Italy, Pied Avocets lay eggs from late April to June, based on adequate weather and environmental conditions. As for this specific case, an estimated cause of such anticipated breeding may be the previous very mild Winter months with little rainfall as well as the breeding ground offering shelter from predators.

Estimation of anthropogenic and volcanic SO2 emissions from satellite data in the presence of snow/ice on the ground

Abstract. Early versions of satellite nadir-viewing UV SO2 data products did not explicitly account for the effects of snow/ice on retrievals. Snow-covered terrain, with its high reflectance in the UV, typically enhances satellite sensitivity to boundary layer pollution. However, a significant fraction of high-quality cloud-free measurements over snow is currently excluded from analyses. This leads to increased uncertainties of satellite emission estimates and potential seasonal biases due to the lack of data in winter months for some high-latitudinal sources. In this study, we investigated how Ozone Monitoring Instrument (OMI) and TROPOspheric Monitoring Instrument (TROPOMI) satellite SO2 measurements over snow-covered surfaces can be used to improve the annual emissions reported in our SO2 emissions catalogue (version 2; Fioletov et al., 2023). Only 100 out of 759 sources listed in the catalogue have 10 % or more of the observations over snow. However, for 40 high-latitude sources, more than 30 % of measurements suitable for emission calculations were made over snow-covered surfaces. For example, in the case of Norilsk, the world's largest SO2 point-source, annual emission estimates in the SO2 catalogue were based only on 3–4 summer months, while the addition of data for snow conditions extends that period to 7 months. Emissions in the SO2 catalogue were based on satellite measurements of SO2 slant column densities (SCDs) that were converted to vertical column densities (VCDs) using site-specific clear-sky air mass factors (AMFs), calculated for snow-free conditions. The same approach was applied to measurements with snow on the ground whereby a new set of constant, site-specific, clear sky with snow AMFs was created, and these were applied to the measured SCDs. Annual emissions were then estimated for each source considering (i) only clear-sky and snow-free days, (ii) only clear-sky with snow days, and (iii) a merged dataset (snow and snow-free conditions). For individual sources, the difference between emissions estimated for snow and snow-free conditions is within ±20 % for three-quarters of smelters and oil and gas sources and with practically no systematic bias. This is excellent consistency given that there is typically a factor of 3–5 difference between AMFs for snow and snow-free conditions. For coal-fired power plants, however, emissions estimated for snow conditions are on average 25 % higher than for snow-free conditions; this difference is likely real and due to larger production (consumption of coal) and emissions in wintertime.

Seasonality of California Central Coast Microseisms

ABSTRACT Linear scattering of ocean wave energy at the ocean–continent transition structure causes the primary microseism at a period of 14 s. Subsequent nonlinear wave–wave interactions produce the secondary microseism signal at half the primary microseism period (Longuet-Higgins, 1950; Haubrich et al., 1963). We use three years (2018–2022) of seismic data from an ongoing microarray deployment in the UC Santa Barbara Sedgwick Reserve, situated in the Santa Ynez Valley, to constrain seasonal and long-term microseismic noise characteristics for this portion of California’s central coast. Ancillary buoy data (spectral data, wave height, wind speed and direction) from the National Oceanic and Atmospheric Administration are used to explore the causal relationship between ocean swell and the generation of microseisms. This region is found to exhibit strong seasonality in the primary and secondary microseism bands (0.05–0.1 and 0.1–0.3 Hz, respectively), with much higher noise levels in the winter compared with the summer, especially for the secondary microseism (15.4 dB). We also observe a systematic shift in the peak frequency of the secondary microseism between the winter (∼0.14 Hz) and summer (∼0.20 Hz) months, which may reflect a difference in sources of secondary microseisms between the two seasons. Local buoy wave height and spectral data are well correlated with seismic power spectra during times of incoming storm swell in winter, indicating locally generated microseisms along the central coast during this season.

Common Cold Coronaviruses Detection at an Academic Hospital Before and During COVID-19 Pandemic

Abstract Background Community mitigation measures implemented during the COVID-19 pandemic altered the seasonality of some respiratory viruses, including the four common cold coronaviruses (CCCs). Since these measures have been relaxed, CCCs have resurged, but limited longitudinal data on CCCs circulation are available to interpret changes in prevalence during the pandemic. Therefore, we defined circulation of the four CCCs before and during the COVID-19 pandemic in Nashville, TN, for insights into the impact of pandemic human coronavirus emergence and associated containment measures on CCCs infections in the general population. Methods We conducted a retrospective cohort study of clinician-ordered respiratory virus panels from 01/01/2018 to 12/31/2022 at Vanderbilt University Medical Center (Nashville, TN). The panels test for common respiratory pathogens, including CCCs (namely HCoV-229E, -NL63, -OC43, and -HKU1). Overall and age-specific detection frequencies for the four CCCs were analyzed. Multiple medical encounters for the same individual were included if they were &amp;gt;14 days apart. The beginning of the pandemic was marked by 04/01/2020, the first day Tennessee’s stay-at-home order was in effect. Results A total of 57,930 samples were tested, and 2,003 (3.5%) were CCC-positive. The most frequently detected CCC was OC43 (n=785; 39.2%), followed by HKU1 (n=510; 25.5%), NL63 (n=510; 25.5%), and 229E (n=237; 11.8%). Before the pandemic, CCCs peaked during winter months. This seasonality was disrupted during the pandemic; circulation virtually ceased in April 2020 and resumed in January 2021, peaking during the spring months of 2021 and 2022. Throughout the study duration, OC43 predominated each season except for the 2019–2020 winter months, when HKU1 was predominant (Figure 1). The seasonality of all four CCCs was generally consistent across age groups; however, 229E was uncommon in children 0–4 years. Figure 1. Detection frequency of the four common cold coronaviruses detected between January 2018 and December 2022 in Nashville, TN, by age group. The dashed line represents the first day Tennessee’s stay-at-home order was in effect. Conclusion The four CCCs circulated off-season in Nashville during the pandemic, exhibiting spring seasonal peaks in 2021 and 2022. Long-term monitoring of CCC circulation is required to determine whether the shift in seasonality becomes a permanent feature of CCC ecology. In addition, further studies are warranted to explain the varying predominance of HCoV-OC43 and HCoV-HKU1.