Multi-scale modeling study of the source contributions to near-surface ozone and sulfur oxides levels over California during the ARCTAS-CARB period

Chronic high surface ozone (O3) levels and the increasing sulfur oxides (SOx = SO2+SO4) ambient concentrations over South Coast (SC) and other areas of California (CA) are affected by both local emissions and long-range transport. In this paper, multi-scale tracer, full-chemistry and adjoint simulations using the STEM atmospheric chemistry model are conducted to assess the contribution of local emission sourcesto SC O3 and to evaluate the impacts of transported sulfur and local emissions on the SC sulfur budgetduring the ARCTAS-CARB experiment period in 2008. Sensitivity simulations quantify contributions of biogenic and fire emissions to SC O3 levels. California biogenic and fire emissions contribute 3–4 ppb to near-surface O3 over SC, with larger contributions to other regions in CA. During a long-range transport event from Asia starting from 22 June, high SOx levels (up to ~0.7 ppb of SO2 and ~1.3 ppb of SO4) is observed above ~6 km, but they did not affect CA surface air quality. The elevated SOx observed at 1–4 km is estimated to enhance surface SOx over SC by ~0.25 ppb (upper limit) on ~24 June. The near-surface SOx levels over SC during the flight week are attributed mostly to local emissions. Two anthropogenic SOx emission inventories (EIs) from the California Air Resources Board (CARB) and the US Environmental Protection Agency (EPA) are compared and applied in 60 km and 12 km chemical transport simulations, and the results are compared withobservations. The CARB EI shows improvements over the National Emission Inventory (NEI) by EPA, but generally underestimates surface SC SOx by about a factor of two. Adjoint sensitivity analysis indicated that SO2 levels at 00:00 UTC (17:00 local time) at six SC surface sites were influenced by previous day maritime emissions over the ocean, the terrestrial emissions over nearby urban areas, and by transported SO2 from the north through both terrestrial and maritime areas. Overall maritime emissions contribute 10–70% of SO2 and 20–60% fine SO4 on-shore and over the most terrestrial areas, with contributions decreasing with in-land distance from the coast. Maritime emissions also modify the photochemical environment, shifting O3 production over coastal SC to more VOC-limited conditions. These suggest an important role for shipping emission controls in reducing fine particle and O3concentrations in SC

Multi-scale modeling study of the source contributions to near-surface ozone and sulfur oxides levels over California during the ARCTAS-CARB period

Chronic high surface ozone (O_3) levels and the increasing sulfur oxides (SO_x = SO_2 + SO_4) ambient concentrations over South Coast (SC) and other areas of California (CA) are affected by both local emissions and long-range transport. In this paper, multi-scale tracer, full-chemistry and adjoint simulations using the STEM atmospheric chemistry model are conducted to assess the contribution of local emission sourcesto SC O_3 and to evaluate the impacts of transported sulfur and local emissions on the SC sulfur budgetduring the ARCTAS-CARB experiment period in 2008. Sensitivity simulations quantify contributions of biogenic and fire emissions to SC O_3 levels. California biogenic and fire emissions contribute 3–4 ppb to near-surface O_3 over SC, with larger contributions to other regions in CA. During a long-range transport event from Asia starting from 22 June, high SO_x levels (up to ~0.7 ppb of SO_2 and ~1.3 ppb of SO_4) is observed above ~6 km, but they did not affect CA surface air quality. The elevated SO_x observed at 1–4 km is estimated to enhance surface SO_x over SC by ~0.25 ppb (upper limit) on ~24 June. The near-surface SO_x levels over SC during the flight week are attributed mostly to local emissions. Two anthropogenic SO_x emission inventories (EIs) from the California Air Resources Board (CARB) and the US Environmental Protection Agency (EPA) are compared and applied in 60 km and 12 km chemical transport simulations, and the results are compared withobservations. The CARB EI shows improvements over the National Emission Inventory (NEI) by EPA, but generally underestimates surface SC SO_x by about a factor of two. Adjoint sensitivity analysis indicated that SO_2 levels at 00:00 UTC (17:00 local time) at six SC surface sites were influenced by previous day maritime emissions over the ocean, the terrestrial emissions over nearby urban areas, and by transported SO_2 from the north through both terrestrial and maritime areas. Overall maritime emissions contribute 10–70% of SO2 and 20–60% fine SO_4 on-shore and over the most terrestrial areas, with contributions decreasing with in-land distance from the coast. Maritime emissions also modify the photochemical environment, shifting O_3 production over coastal SC to more VOC-limited conditions. These suggest an important role for shipping emission controls in reducing fine particle and O_3 concentrations in SC

Assessing regional scale predictions of aerosols, marine stratocumulus, and their interactions during VOCALS-REx using WRF-Chem

This study assesses the ability of the recent chemistry version (v3.3) of the Weather Research and Forecasting (WRF-Chem) model to simulate boundary layer structure, aerosols, stratocumulus clouds, and energy fluxes over the Southeast Pacific Ocean. Measurements from the VAMOS Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx) and satellite retrievals (i.e., products from the MODerate resolution Imaging Spectroradiometer (MODIS), Clouds and Earth's Radiant Energy System (CERES), and GOES-10) are used for this assessment. The Morrison double-moment microphysics scheme is newly coupled with interactive aerosols in the model. The 31-day (15 October–16 November 2008) WRF-Chem simulation with aerosol-cloud interactions (AERO hereafter) is also compared to a simulation (MET hereafter) with fixed cloud droplet number concentrations in the microphysics scheme and simplified cloud and aerosol treatments in the radiation scheme. The well-simulated aerosol quantities (aerosol number, mass composition and optical properties), and the inclusion of full aerosol-cloud couplings lead to significant improvements in many features of the simulated stratocumulus clouds: cloud optical properties and microphysical properties such as cloud top effective radius, cloud water path, and cloud optical thickness. In addition to accounting for the aerosol direct and semi-direct effects, these improvements feed back to the simulation of boundary-layer characteristics and energy budgets. Particularly, inclusion of interactive aerosols in AERO strengthens the temperature and humidity gradients within the capping inversion layer and lowers the marine boundary layer (MBL) depth by 130 m from that of the MET simulation. These differences are associated with weaker entrainment and stronger mean subsidence at the top of the MBL in AERO. Mean top-of-atmosphere outgoing shortwave fluxes, surface latent heat, and surface downwelling longwave fluxes are in better agreement with observations in AERO, compared to the MET simulation. Nevertheless, biases in some of the simulated meteorological quantities (e.g., MBL temperature and humidity) and aerosol quantities (e.g., underestimations of accumulation mode aerosol number) might affect simulated stratocumulus and energy fluxes over the Southeastern Pacific, and require further investigation. The well-simulated timing and outflow patterns of polluted and clean episodes demonstrate the model's ability to capture daily/synoptic scale variations of aerosol and cloud properties, and suggest that the model is suitable for studying atmospheric processes associated with pollution outflow over the ocean. The overall performance of the regional model in simulating mesoscale clouds and boundary layer properties is encouraging and suggests that reproducing gradients of aerosol and cloud droplet concentrations and coupling cloud-aerosol-radiation processes are important when simulating marine stratocumulus over the Southeast Pacific

Особливості квітування та плодоношення Ailanthus Altissima (Mill.) в умовах правобережного лісостепу і степу України

The authors have investigated duration and period of flowering of plants (Ailanthus altissima (Mill.)) under the conditions of the right bank forest steppe and the Ukrainian steppe. We have determined that the duration and period of flowering of introduces plants to a large extent depends on the climatic conditions in which they grow. A. altissima plants are stated to belong to a group of plants with medium flowering duration. The abundance of flowering of A. altissima plants in the conditions of the right bank forest-steppe and steppe of Ukraine is estimated. The length of laying and reaching the fruits of A. altissima plants is determined to occur at different periods of the growing season, depending on the average daily temperature of the air and the place of growth of this species. We have also revealed that A. altissima trees enter the fruiting phase at the age of 10‑15 years in the southern regions of the steppe and in the 15–18 years under the conditions of the right bank forest-steppe. A. altissima during the growing season has stable flowering and fruiting in the investigated plants. The average rate of flowering abundance in the conditions of the right bank forest-steppe was stable and was estimated at 4.5, and in the steppe – 5 points. The fertility abundance index in the right bank forest-steppe and the steppe was stable and quite high – 4.0 and 5.0 points. The authors have presented the results of the study of the average parameters of the abundance of flowering and fruiting A. altissima, in green plantations growing in the National Dendrology Park "Sofiyivka" of the National Academy of Sciences of Ukraine, Uman NPC, Uman and Uman district, Dendrology Park "Veseli Bokovenki" Kirovograd region, urban area, Chethelnik Vinnitsa region, Odessa city, and Mykolayiv city. A. altissima flowering was defined to be the most noticeable in streets of Odessa and Mykolaiv (5.0 points). We evaluated plants growing in the Dendrology Park Vesely Bokoveniy, Kirovograd region as 4.5 points. Plants growing in the National Dendrology Park "Sofiyivka" of Cherkasy region were also evaluated as 4.5 points. The fruit harvesting phase in the National Dendrology Park "Sofiyivka" begins at the end of August and lasts for 35–40 days. In Odessa and Mykolaiv regions, the term of fruit reaching is much lower. The achievement phase begins at the end of July and lasts for 30–35 days, which confirms the difference in the duration of seed formation in different regions. The decorative nature of the fruits is determined by their size, shape, color, and time of reaching and falling from the plants.Досліджено тривалість і період квітування рослин (Ailanthus altissima Mill.) в умовах Правобережного Лісостепу і Степу України. Визначено, що тривалість і період квітування рослин інтродуцентів значною мірою залежить від кліматичних умов, в яких вони зростають. Досліджено, що рослини A. altissima належать до групи рослин із середньою тривалістю квітування. Оцінено рясність квітування рослин A. altissima в умовах Правобережного Лісостепу і Степу України. Визначено, що тривалість зав'язування та достигання плодів у рослин A. altissima настає в різні строки вегетаційного періоду залежно від середньодобової температури повітря та місця зростання цього виду. Досліджено, що дерева A. altissima у фазу плодоношення вступають у віці 10–15 років у південних областях Степу і в 15–18 років – в умовах Правобережного Лісостепу. Встановлено, що у досліджуваних рослин A. altissima впродовж вегетаційного періоду спостерігається стабільне квітування та плодоношення. Середній показник рясності квітування в умовах Правобережного Лісостепу був стабільним і оцінювався балом 4,5, а в Степу – 5 балів. Показник рясності плодоношення в Правобережному Лісостепу і Степу був стабільним і досить високим – 4,0 та 5,0 балів. Наведено результати дослідження середніх показників рясності квітування та плодоношення A. altissima, які зростають у Національному дендрологічному парку "Софіївка" НАН України, Уманському НУС, у зелених насадженнях. Умані та Уманського району, дендрологічному парку "Веселі Боковеньки" Кіровоградської обл. смт Чечельник Вінницької обл., в Одесі та Миколаєві

The effect of fluoride on enamel and dentin formation in the uremic rat incisor

Renal impairment in children is associated with tooth defects that include enamel pitting and hypoplasia. However, the specific effects of uremia on tooth formation are not known. In this study, we used rat mandibular incisors, which continuously erupt and contain all stages of tooth formation, to characterize the effects of uremia on tooth formation. We also tested the hypothesis that uremia aggravates the fluoride (F)-induced changes in developing teeth. Rats were subjected to a two-stage 5/6 nephrectomy or sham operation and then exposed to 0 (control) or 50 ppm NaF in drinking water for 14 days. The effects of these treatments on food intake, body growth rate, and biochemical serum parameters for renal function and calcium metabolism were monitored. Nephrectomy reduced food intake and weight gain. Intake of F by nephrectomized rats increased plasma F levels twofold and further decreased food intake and body weight gain. Uremia affected formation of dentin and enamel and was more extensive than the effect of F alone. Uremia also significantly increased predentin width and induced deposition of large amounts of osteodentin-like matrix-containing cells in the pulp chamber. In enamel formation, the cells most sensitive to uremia were the transitional-stage ameloblasts. These data demonstrate that intake of F by rats with reduced renal function impairs F clearance from the plasma and aggravates the already negative effects of uremia on incisor tooth development

Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study

A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4