46 research outputs found
Penggunaan Gaya Bahasa Sarkasme pada Film Lara Ati Karya Bayu Skak
Gaya bahasa sarkasme adalah fokus dari penelitian ini dan permasalahan yang dikaji dalam penelitian ini adalah (1) bagaimanakah bentuk gaya bahasa sarkasme pada film Lara Ati Karya Bayu Skak? (2) bagaimanakah makna gaya bahasa sarkasme yang terdapat pada film Lara Ati Karya Bayu Skak?. Berdasarkan permasalahan tersebut, tujuan penelitian ini adalah (1) Mendeskripsikan bentuk gaya bahasa sarkasme yang terdapat pada film Lara Ati Karya Bayu Skak (2) Mendeskripsikan makna gaya bahasa sarkasme yang terdapat pada film Lara Ati Karya Bayu Skak. Metode penelitian ini adalah metode deskriptif dengan data analisis kualitatif. Teknik pengumpulan data dalam penelitian ini menggunakan teknik simak dan catat. Hasil penelitian menunjukkan gaya bahasa sarkasme dalam film Lara Ati Karya Bayu Skak terdapat 23 data bentuk dan makna gaya bahasa sarkasme yang terdiri dari ejekan dan sindiran. Penelitian ini diharapkan dapat menjadi referensi bagi pembaca, khususnya yang ingin melakukan penelitian lebih mendalam tentang gaya bahasa sarkasme
Ilmakehän aerosolihiukkasten vaihtelun luonnolliset ja ihmisperäiset syyt
Aerosol particles are everywhere in the atmosphere. They are a key factor in many important processes in the atmosphere, including cloud formation, scattering of incoming solar radiation and air chemistry. The aerosol particles have relatively short lifetimes in lower atmosphere, typically from days to weeks, and thus they have a high spatial and temporal variability. This thesis concentrates on the extent and reasons of sub-micron aerosol particle variability in the lower atmosphere, using both global atmospheric models and analysis of observational data.
Aerosol number size distributions in the lower atmosphere are affected strongly by the new particle formation. Perhaps more importantly, a strong influence new particle formation is also evident in the cloud condensation nuclei (CCN) concentrations, suggesting a major role of the sulphuric acid driven new particle formation in the climate system.
In this thesis, the sub-micron aerosol number size distributions in the European regional background air were characterized for the first time from consistent, homogenized and comparable datasets.
Some recent studies have suggested that differences in aerosol emissions between weekdays could also affect the weather via aerosol-cloud interactions. In this thesis, the weekday-to-weekday variation of CCN sized aerosol number concentrations in Europe were found to be much smaller than expected from earlier studies, based on particle mass measurements. This result suggests that a lack of week-day variability in meteorology is not necessarily a sign of weak aerosol-cloud interactions.
An analysis of statistically significant trends in past decades of measured aerosol number concentrations from Europe, North America, Pacific islands and Antarctica generally show decreases in concentrations. The analysis of these changes show that a potential explanation for the decreasing trends is the general reduction of anthropogenic emissions, especially SO2, although a combination of several drivers for these changes in the number concentrations are likely.
The IPCC representative emission pathways prognose radical reductions of anthropogenic emissions in the next decades, especially of sulphur dioxide, that will most likely cause strong reduction in the present-day cooling effect of the atmospheric aerosols. The model simulations of this thesis show that effect will cause strong additional positive forcing on the atmosphere, possibly causing further increase in the near-surface mean temperatures. The effect was further magnified when new particle formation in atmosphere was also considered in the model calculations. Strong reductions in primary aerosol emissions and especially secondary aerosol precursors should be thus considered with caution.Ilmakehässä on kaasujen ja höyryjen lisäksi erittäin pieniä hiukkasia. Nämä usein näkymättömän pienet aerosolihiukkaset ovat hyvin merkittäviä sekä terveys- että ilmastonäkökulmista. Hiukkaset voivat joko lämmittää ilmastoa absorboimalla valoa, tai viilentää ilmastoa sirottamalla auringon säteilyä tai muuttamalla pilvien ominaisuuksia.
Väitöskirjatyössä on tutkittu näiden aerosolihiukkasten lähteitä, vaihtelua ja pitoisuuksia, kartoittaen sekä nykytilannetta että lähimenneisyyttä. Väitöskirjassa on myös arvioitu hiukkasten merkitystä ilmastojärjestelmälle ja arvioitu muutoksia ilmastossa, mikäli arviot tulevaisuuden ihmisperäisten ilmansaasteiden päästöjen kehityksestä pitävät paikkaansa. Välineinä on käytetty globaalia ilmastomallia, sekä pitkien mittausaikasarjojen analyysiä.
Tuloksina on ensimmäinen johdonmukaisesti rakennettu kokoelma Euroopan tausta-ilman aerosolihiukkasten lukumääräkokojakaumista ja -pitoisuuksista, sekä uusi arvio pilviin vaikuttavien aerosolihiukkasten viikoittaisesta vaihtelusta. Ilmastomallisimulaatiot osoittavat sen, että globaalit aerosolihiukkasten pitoisuudet ovat herkkiä ilmakehässä olevan rikkihapon määrälle kaasu-hiukkas muuntuman kautta. Koska rikkihappoa muodostuu ilmakehässä rikkidioksidista, tämä tekee aerosolihiukkaspitoisuudet myös herkäksi rikkidioksidin päästöille.
Väitöskirjassa osoitetaan, että pienhiukkasten pitoisuudet Euroopassa, Pohjois-Amerikassa ja Tyynellä valtamerellä ovat vähentyneet viimeisten vuosikymmenien aikana. Vaikka varmaa syytä vähentymiseen ei vielä tiedetä, nämä pienhiukkasten trendit ovat yhtäpitäviä samanaikaisten rikkidioksidin päästövähennyksien kanssa. Onkin syytä olettaa, että ilmankehän pienhiukkasten määrä, ja siten mahdollisesti myös niiden viilentävät ilmastovaikutukset, seuraavat monilla alueilla rikkidioksidin päästöjä, vaikkakin myös muilla pienhiukkasten lähteillä on toki merkittäviä vaikutuksia hiukkasten pitoisuuksiin.
Kansainvälinen ilmastopaneelin käyttämien arvioiden mukaan rikkidioksidin ihmisperäiset päästöt vähentyvät lähes esiteolliselle tasolle seuraavan sadan vuoden aikana. Väitöskirjassa tehtyjen ilmastosimulaatioissa myös pienhiukkasten ilmastoa viilentävät vaikutukset tällöin vähentyvät merkittävästi. Onkin vaarana, että ilmaston lämpeneminen voi siten olla jopa arvioitua voimakkaampaa tulevaisuudessa. Erilaisten ilmakehän epäpuhtauksien, erityisesti rikin, vähentämisestä sovittaessa olisikin tarpeen pyrkiä selvittää myös tällaiset epäsuorat haitalliset ilmastovaikutukset
Substantial large-scale feedbacks between natural aerosols and climate
The terrestrial biosphere is an important source of natural aerosol. Natural aerosol sources alter climate, but are also strongly controlled by climate, leading to the potential for natural aerosol-climate feedbacks. Here we use a global aerosol model to make an assessment of terrestrial natural aerosol-climate feedbacks, constrained by observations of aerosol number. We find that warmer-than-average temperatures are associated with higher-than-average number concentrations of large (>100 nm diameter) particles, particularly during the summer. This relationship is well reproduced by the model and is driven by both meteorological variability and variability in natural aerosol from biogenic and landscape fire sources. We find that the calculated extratropical annual mean aerosol radiative effect (both direct and indirect) is negatively related to the observed global temperature anomaly, and is driven by a positive relationship between temperature and the emission of natural aerosol. The extratropical aerosol-climate feedback is estimated to be -0.14 W m(-2) K-1 for landscape fire aerosol, greater than the -0.03 W m(-2) K-1 estimated for biogenic secondary organic aerosol. These feedbacks are comparable in magnitude to other biogeochemical feedbacks, highlighting the need for natural aerosol feedbacks to be included in climate simulations.Peer reviewe
Versioning data is about more than revisions : A conceptual framework and proposed principles
A dataset, small or big, is often changed to correct errors, apply new algorithms, or add new data (e.g., as part of a time series), etc. In addition, datasets might be bundled into collections, distributed in different encodings or mirrored onto different platforms. All these differences between versions of datasets need to be understood by researchers who want to cite the exact version of the dataset that was used to underpin their research. Failing to do so reduces the reproducibility of research results. Ambiguous identification of datasets also impacts researchers and data centres who are unable to gain recognition and credit for their contributions to the collection, creation, curation and publication of individual datasets. Although the means to identify datasets using persistent identifiers have been in place for more than a decade, systematic data versioning practices are currently not available. In this work, we analysed 39 use cases and current practices of data versioning across 33 organisations. We noticed that the term ‘version’ was used in a very general sense, extending beyond the more common understanding of ‘version’ to refer primarily to revisions and replacements. Using concepts developed in software versioning and the Functional Requirements for Bibliographic Records (FRBR) as a conceptual framework, we developed six foundational principles for versioning of datasets: Revision, Release, Granularity, Manifestation, Provenance and Citation. These six principles provide a high-level framework for guiding the consistent practice of data versioning and can also serve as guidance for data centres or data providers when setting up their own data revision and version protocols and procedures.Peer reviewe
Cloud condensation nuclei production associated with atmospheric nucleation : a synthesis based on existing literature and new results
This paper synthesizes the available scientific information connecting atmospheric nucleation with subsequent cloud condensation nuclei (CCN) formation. We review both observations and model studies related to this topic, and discuss the potential climatic implications. We conclude that CCN production associated with atmospheric nucleation is both frequent and widespread phenomenon in many types of continental boundary layers, and probably also over a large fraction of the free troposphere. The contribution of nucleation to the global CCN budget spans a relatively large uncertainty range, which, together with our poor understanding of aerosol-cloud interactions, results in major uncertainties in the radiative forcing by atmospheric aerosols. In order to better quantify the role of atmospheric nucleation in CCN formation and Earth System behavior, more information is needed on (i) the factors controlling atmospheric CCN production and (ii) the properties of both primary and secondary CCN and their interconnections. In future investigations, more emphasis should be put on combining field measurements with regional and large-scale model studies.Peer reviewe
Trends in atmospheric new-particle formation : 16 years of observations in a boreal-forest environment
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SALSA - a sectional aerosol module for large scale applications
"The sectional aerosol module SALSA is introduced. The model has been designed to be implemented in large scale climate models, which require both accuracy and computational efficiency. We have used multiple methods to reduce the computational burden of different aerosol processes to optimize the model performance without losing physical features relevant to problematics of climate importance. The optimizations include limiting the chemical compounds and physical processes available in different size sections of aerosol particles; division of the size distribution into size sections using size sections of variable width depending on the sensitivity of microphysical processing to the particles sizes; the total amount of size sections to describe the size distribution is kept to the minimum; furthermore, only the relevant microphysical processes affecting each size section are calculated. The ability of the module to describe different microphysical processes was evaluated against explicit microphysical models and several microphysical models used in air quality models. The results from the current module show good consistency when compared to more explicit models. Also, the module was used to simulate a new particle formation event typical in highly polluted conditions with comparable results to more explicit model setup.""The sectional aerosol module SALSA is introduced. The model has been designed to be implemented in large scale climate models, which require both accuracy and computational efficiency. We have used multiple methods to reduce the computational burden of different aerosol processes to optimize the model performance without losing physical features relevant to problematics of climate importance. The optimizations include limiting the chemical compounds and physical processes available in different size sections of aerosol particles; division of the size distribution into size sections using size sections of variable width depending on the sensitivity of microphysical processing to the particles sizes; the total amount of size sections to describe the size distribution is kept to the minimum; furthermore, only the relevant microphysical processes affecting each size section are calculated. The ability of the module to describe different microphysical processes was evaluated against explicit microphysical models and several microphysical models used in air quality models. The results from the current module show good consistency when compared to more explicit models. Also, the module was used to simulate a new particle formation event typical in highly polluted conditions with comparable results to more explicit model setup.""The sectional aerosol module SALSA is introduced. The model has been designed to be implemented in large scale climate models, which require both accuracy and computational efficiency. We have used multiple methods to reduce the computational burden of different aerosol processes to optimize the model performance without losing physical features relevant to problematics of climate importance. The optimizations include limiting the chemical compounds and physical processes available in different size sections of aerosol particles; division of the size distribution into size sections using size sections of variable width depending on the sensitivity of microphysical processing to the particles sizes; the total amount of size sections to describe the size distribution is kept to the minimum; furthermore, only the relevant microphysical processes affecting each size section are calculated. The ability of the module to describe different microphysical processes was evaluated against explicit microphysical models and several microphysical models used in air quality models. The results from the current module show good consistency when compared to more explicit models. Also, the module was used to simulate a new particle formation event typical in highly polluted conditions with comparable results to more explicit model setup."Peer reviewe
Sensitivity of aerosol concentrations and cloud properties to nucleation and secondary organic distribution in ECHAM5-HAM global circulation model
The global aerosol-climate model ECHAM5-HAM was modified to improve the representation of new particle formation in the boundary layer. Activation-type nucleation mechanism was introduced to produce observed nucleation rates in the lower troposphere. A simple and computationally efficient model for biogenic secondary organic aerosol (BSOA) formation was implemented. Here we study the sensitivity of the aerosol and cloud droplet number concentrations (CDNC) to these additions. Activation-type nucleation significantly increases aerosol number concentrations in the boundary layer. Increased particle number concentrations have a significant effect also on cloud droplet number concentrations and therefore on cloud properties. We performed calculations with activation nucleation coefficient values of 2 x 10(-7) s(-1), 2 x 10(-6) s(-1) and 2 x 10(-5) s(-1) to evaluate the sensitivity to this parameter. For BSOA we have used yields of 0.025, 0.07 and 0.15 to estimate the amount of monoterpene oxidation products available for condensation. The hybrid BSOA formation scheme induces large regional changes to size distribution of organic carbon, and therefore affects particle optical properties and cloud droplet number concentrations locally. Although activation-type nucleation improves modeled aerosol number concentrations in the boundary layer, the use of a global activation coefficient generally leads to overestimation of aerosol number. Overestimation can also arise from underestimation of primary emissions.The global aerosol-climate model ECHAM5-HAM was modified to improve the representation of new particle formation in the boundary layer. Activation-type nucleation mechanism was introduced to produce observed nucleation rates in the lower troposphere. A simple and computationally efficient model for biogenic secondary organic aerosol (BSOA) formation was implemented. Here we study the sensitivity of the aerosol and cloud droplet number concentrations (CDNC) to these additions. Activation-type nucleation significantly increases aerosol number concentrations in the boundary layer. Increased particle number concentrations have a significant effect also on cloud droplet number concentrations and therefore on cloud properties. We performed calculations with activation nucleation coefficient values of 2 x 10(-7) s(-1), 2 x 10(-6) s(-1) and 2 x 10(-5) s(-1) to evaluate the sensitivity to this parameter. For BSOA we have used yields of 0.025, 0.07 and 0.15 to estimate the amount of monoterpene oxidation products available for condensation. The hybrid BSOA formation scheme induces large regional changes to size distribution of organic carbon, and therefore affects particle optical properties and cloud droplet number concentrations locally. Although activation-type nucleation improves modeled aerosol number concentrations in the boundary layer, the use of a global activation coefficient generally leads to overestimation of aerosol number. Overestimation can also arise from underestimation of primary emissions.The global aerosol-climate model ECHAM5-HAM was modified to improve the representation of new particle formation in the boundary layer. Activation-type nucleation mechanism was introduced to produce observed nucleation rates in the lower troposphere. A simple and computationally efficient model for biogenic secondary organic aerosol (BSOA) formation was implemented. Here we study the sensitivity of the aerosol and cloud droplet number concentrations (CDNC) to these additions. Activation-type nucleation significantly increases aerosol number concentrations in the boundary layer. Increased particle number concentrations have a significant effect also on cloud droplet number concentrations and therefore on cloud properties. We performed calculations with activation nucleation coefficient values of 2 x 10(-7) s(-1), 2 x 10(-6) s(-1) and 2 x 10(-5) s(-1) to evaluate the sensitivity to this parameter. For BSOA we have used yields of 0.025, 0.07 and 0.15 to estimate the amount of monoterpene oxidation products available for condensation. The hybrid BSOA formation scheme induces large regional changes to size distribution of organic carbon, and therefore affects particle optical properties and cloud droplet number concentrations locally. Although activation-type nucleation improves modeled aerosol number concentrations in the boundary layer, the use of a global activation coefficient generally leads to overestimation of aerosol number. Overestimation can also arise from underestimation of primary emissions.Peer reviewe
Towards an online-coupled chemistry-climate model: evaluation of trace gases and aerosols in COSMO-ART
Peer reviewe