22 research outputs found

    Emerging Standards and the Hybrid Model for Organizing Scientific Events During and After The COVID-19 Pandemic.

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    Since the beginning of 2020, the COVID-19 pandemic has dramatically influenced almost every aspect of human life. Activities requiring human gatherings have either been postponed, cancelled, or held completely virtually. To supplement lack of in-person contact, people have increasingly turned to virtual settings on-line, advantages of which include increased inclusivity and accessibility and reduction of carbon footprint. However, emerging online technologies cannot fully replace, in-person scientific events. In-person meetings are not susceptible to poor internet connectivity problems, and they provide novel opportunities for socialization, creating new collaborations, and sharing ideas. To continue such activities, a hybrid model for scientific events could be a solution offering both in-person and virtual components. While participants can freely choose the mode of their participation, virtual meetings would most benefit those who cannot attend in-person due to the limitations. In-person portions of meetings should be organized with full consideration of prevention and safety strategies including risk assessment and mitigation, venue and environmental sanitation, participant protection and disease prevention, and promoting the hybrid model. This new way of interaction between scholars can be considered as a part of a resilience system which was neglected previously and should become a part of routine practice in scientific community

    Modelling the chemistry and transport of bromoform within a sea breeze driven convective system during the SHIVA Campaign

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    We carry out a case study of the transport and chemistry of bromoform and its product gases (PGs) in a sea breeze driven convective episode on 19 November 2011 along the North West coast of Borneo during the "Stratospheric ozone: Halogen Impacts in a Varying Atmosphere" (SHIVA) campaign. We use ground based, ship, aircraft and balloon sonde observations made during the campaign, and a 3-D regional online transport and chemistry model capable of resolving clouds and convection explicitly that includes detailed bromine chemistry. The model simulates the temperature, wind speed, wind direction fairly well for the most part, and adequately captures the convection location, timing, and intensity. The simulated transport of bromoform from the boundary layer up to 12 km compares well to aircraft observations to support our conclusions. The model makes several predictions regarding bromine transport from the boundary layer to the level of convective detrainment (11 to 12 km). First, the majority of bromine undergoes this transport as bromoform. Second, insoluble organic bromine carbonyl species are transported to between 11 and 12 km, but only form a small proportion of the transported bromine. Third, soluble bromine species, which include bromine organic peroxides, hydrobromic acid (HBr), and hypobromous acid (HOBr), are washed out efficiently within the core of the convective column. Fourth, insoluble inorganic bromine species (principally Br2) are not washed out of the convective column, but are also not transported to the altitude of detrainment in large quantities. We expect that Br2 will make a larger relative contribution to the total vertical transport of bromine atoms in scenarios with higher CHBr3 mixing ratios in the boundary layer, which have been observed in other regions. Finally, given the highly detailed description of the chemistry, transport and washout of bromine compounds within our simulations, we make a series of recommendations about the physical and chemical processes that should be represented in 3-D chemical transport models (CTMs) and chemistry climate models (CCMs), which are the primary theoretical means of estimating the contribution made by CHBr3 and other very short-lived substances (VSLS) to the stratospheric bromine budget

    A multi-model intercomparison of halogenated very short-lived substances (TransCom-VSLS): Linking oceanic emissions and tropospheric transport for a reconciled estimate of the stratospheric source gas injection of bromine

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    Abstract. The first concerted multi-model intercomparison of halogenated very short-lived substances (VSLS) has been performed, within the framework of the ongoing Atmospheric Tracer Transport Model Intercomparison Project (TransCom). Eleven global models or model variants participated (nine chemical transport models and two chemistry–climate models) by simulating the major natural bromine VSLS, bromoform (CHBr3) and dibromomethane (CH2Br2), over a 20-year period (1993–2012). Except for three model simulations, all others were driven offline by (or nudged to) reanalysed meteorology. The overarching goal of TransCom-VSLS was to provide a reconciled model estimate of the stratospheric source gas injection (SGI) of bromine from these gases, to constrain the current measurement-derived range, and to investigate inter-model differences due to emissions and transport processes. Models ran with standardised idealised chemistry, to isolate differences due to transport, and we investigated the sensitivity of results to a range of VSLS emission inventories. Models were tested in their ability to reproduce the observed seasonal and spatial distribution of VSLS at the surface, using measurements from NOAA's long-term global monitoring network, and in the tropical troposphere, using recent aircraft measurements – including high-altitude observations from the NASA Global Hawk platform. The models generally capture the observed seasonal cycle of surface CHBr3 and CH2Br2 well, with a strong model–measurement correlation (r  ≥  0.7) at most sites. In a given model, the absolute model–measurement agreement at the surface is highly sensitive to the choice of emissions. Large inter-model differences are apparent when using the same emission inventory, highlighting the challenges faced in evaluating such inventories at the global scale. Across the ensemble, most consistency is found within the tropics where most of the models (8 out of 11) achieve best agreement to surface CHBr3 observations using the lowest of the three CHBr3 emission inventories tested (similarly, 8 out of 11 models for CH2Br2). In general, the models reproduce observations of CHBr3 and CH2Br2 obtained in the tropical tropopause layer (TTL) at various locations throughout the Pacific well. Zonal variability in VSLS loading in the TTL is generally consistent among models, with CHBr3 (and to a lesser extent CH2Br2) most elevated over the tropical western Pacific during boreal winter. The models also indicate the Asian monsoon during boreal summer to be an important pathway for VSLS reaching the stratosphere, though the strength of this signal varies considerably among models. We derive an ensemble climatological mean estimate of the stratospheric bromine SGI from CHBr3 and CH2Br2 of 2.0 (1.2–2.5) ppt,  ∼  57 % larger than the best estimate from the most recent World Meteorological Organization (WMO) Ozone Assessment Report. We find no evidence for a long-term, transport-driven trend in the stratospheric SGI of bromine over the simulation period. The transport-driven interannual variability in the annual mean bromine SGI is of the order of ±5 %, with SGI exhibiting a strong positive correlation with the El Niño–Southern Oscillation (ENSO) in the eastern Pacific. Overall, our results do not show systematic differences between models specific to the choice of reanalysis meteorology, rather clear differences are seen related to differences in the implementation of transport processes in the models. </jats:p

    N2_2O Temporal Variability from the Middle Troposphere to the Middle Stratosphere Based on Airborne and Balloon-Borne Observations during the Period 1987–2018

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    Nitrous oxide (N2_2O) is the fourth most important greenhouse gas in the atmosphere and is considered the most important current source gas emission for global stratospheric ozone depletion (O3_3). It has natural and anthropogenic sources, mainly as an unintended by-product of food production activities. This work examines the identification and quantification of trends in the N2_2O concentration from the middle troposphere to the middle stratosphere (MTMS) by in situ and remote sensing observations. The temporal variability of N2_2O is addressed using a comprehensive dataset of in situ and remote sensing N2_2O concentrations based on aircraft and balloon measurements in the MTMS from 1987 to 2018. We determine N2_2O trends in the MTMS, based on observations. This consistent dataset was also used to study the N2_2O seasonal cycle to investigate the relationship between abundances and its emission sources through zonal means. The results show a long-term increase in global N2_2O concentration in the MTMS with an average of 0.89 ± 0.07 ppb/yr in the troposphere and 0.96 ± 0.15 ppb/yr in the stratosphere, consistent with 0.80 ppb/yr derived from ground-based measurements and 0.799 ± 0.024 ppb/yr ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) satellite measurements

    N2O Temporal Variability from the Middle Troposphere to the Middle Stratosphere Based on Airborne and Balloon-Borne Observations during the Period 1987–2018

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    Nitrous oxide (N2O) is the fourth most important greenhouse gas in the atmosphere and is considered the most important current source gas emission for global stratospheric ozone depletion (O3 ). It has natural and anthropogenic sources, mainly as an unintended by-product of food production activities. This work examines the identification and quantification of trends in the N2O concentration from the middle troposphere to the middle stratosphere (MTMS) by in situ and remote sensing observations. The temporal variability of N2O is addressed using a comprehensive dataset of in situ and remote sensing N2O concentrations based on aircraft and balloon measurements in the MTMS from 1987 to 2018. We determine N2O trends in the MTMS, based on observations. This consistent dataset was also used to study the N2O seasonal cycle to investigate the relationship between abundances and its emission sources through zonal means. The results show a longterm increase in global N2O concentration in the MTMS with an average of 0.89 ± 0.07 ppb/yr in the troposphere and 0.96 ± 0.15 ppb/yr in the stratosphere, consistent with 0.80 ppb/yr derived from ground-based measurements and 0.799 ± 0.024 ppb/yr ACE-FTS (Atmospheric Chemistry Experiment Fourier Transform Spectrometer) satellite measurements

    Stratospheric aerosol - Observations, processes, and impact on climate

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    Interest in stratospheric aerosol and its role in climate have increased over the last decade due to the observed increase in stratospheric aerosol since 2000 and the potential for changes in the sulfur cycle induced by climate change. This review provides an overview about the advances in stratospheric aerosol research since the last comprehensive assessment of stratospheric aerosol was published in 2006. A crucial development since 2006 is the substantial improvement in the agreement between in situ and space-based inferences of stratospheric aerosol properties during volcanically quiescent periods. Furthermore, new measurement systems and techniques, both in situ and space based, have been developed for measuring physical aerosol properties with greater accuracy and for characterizing aerosol composition. However, these changes induce challenges to constructing a long-term stratospheric aerosol climatology. Currently, changes in stratospheric aerosol levels less than 20% cannot be confidently quantified. The volcanic signals tend to mask any nonvolcanically driven change, making them difficult to understand. While the role of carbonyl sulfide as a substantial and relatively constant source of stratospheric sulfur has been confirmed by new observations and model simulations, large uncertainties remain with respect to the contribution from anthropogenic sulfur dioxide emissions. New evidence has been provided that stratospheric aerosol can also contain small amounts of nonsulfate matter such as black carbon and organics. Chemistry-climate models have substantially increased in quantity and sophistication. In many models the implementation of stratospheric aerosol processes is coupled to radiation and/or stratospheric chemistry modules to account for relevant feedback processes

    NEURALNET 2005: Komputerowy system edukacyjny wspomagający proces wykorzystania sztucznych sieci neuronowych w rolnictwie

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    The purpose of this project was to develop an interactive computer application pursuant to software engineering standards that would support education in the field of constructing and operating selected artificial neural network topologies. The project is designed to investigate selected problems having to do with the generation and operation of perceptron and radial network and help to present the networks' operating principles as classification instruments in a case of identifying flower varieties for practical purposes.Celem pracy było wytworzenie, zgodnie ze standardami inżynierii oprogramowania, interaktywnej aplikacji komputerowej, wspomagającej proces edukacyjny w zakresie konstrukcji oraz eksploatacji wybranych topologii sztucznych sieci neuronowych w kontekście wykorzystania ich w rolnictwie. Ma ona przybliżyć wybrane zagadnienia z zakresu generowania i eksploatacji sieci typu perceptron i sieci radialnej oraz praktycznie zaprezentować zasadę działania tych sieci jako narzędzi klasyfikacyjnych na przykładzie zadania identyfikacji odmian kwiatów

    Wykorzystanie internetowych systemów informatycznych EDUIR I BADNAK w procesie kształcenia i zarządzania badaniami w inżynierii rolniczej

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    Considering dynamics of educational processes, their teaching goals and organizational forms and also research management, faculty members face increasing requirements. Consequently, time devoted to research activities becomes gradually reduced. Implementing specific information systems that assist educational processes and research management may improve the situation while increasing efficiency. In this work Internet applications supporting teaching of agricultural engineering and also research management, were developed. Providing sequential educational materials prepared by agricultural engineering faculty members, the program allows them to verify in various forms students' achievements and to analyze the teaching process. Learning goals as well as verifying tests are based on static and dynamic pictures. Systems implementation was preceded by object modeling in the UML notation. Both latest Internet technological inventions, PHP 5 and ASP.NET, were selected. The two applications work with the SQL Server 2000 database system, supported by an original safety system developed for data confidentiality.Proces kształcenia, z uwagi na swoją dynamikę obejmującą treści nauczania jak i jego formy organizacyjne stawia coraz większe wymagania pracownikom nauki. Konsekwencją tego jest permanentne uszczuplanie czasu przeznaczonego na badania naukowe. Częściową poprawę tego stanu rzeczy, przy jednoczesnym zwiększeniu efektywności nauczania możemy osiągnąć poprzez wykorzystanie specjalistycznych systemów informatycznych wspomagających proces kształcenia. Autorzy podjęli udaną próbę budowy aplikacji internetowej pomocnej w nauczaniu studentów w obszarze inżynierii rolniczej. Wspiera ona organizację procesu kształcenia, udostępnia sekwencyjnie materiały edukacyjnych przygotowane przez wykładowców, pozwala na różnorodne formy weryfikacji wiedzy studentów oraz dokonuje analizy procesu nauczania. Treści nauczania jak i pytania testowe bazują na stycznych i dynamicznych obrazach. Etapy poprzedzające implementację systemu obejmowały modelowanie obiektowe w notacji UML, czego efektem były wielopoziomowe diagramy przypadków użycia oraz diagramy klas. Jako narzędzia programistyczne wybrano jedną z najnowszych technologii internetowych, jakim jest PHP 5. Aplikacja współpracuje z systemem bazodanowym SQL Server 2000, a zaproponowany oryginalny system zabezpieczeń gwarantuje poufność danych
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