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  • particles
  • Water vapor clings to aerosol particles floating in the atmosphere and eventually forms a water and dust seed that becomes a cloud. (dailycaller.com)
  • Likewise, the more aerosol particles suspended in the atmosphere, the greater the ability of these particles either to scatter sunlight back to space and cool the planet or to absorb sunlight in the atmosphere, thereby warming the atmosphere while cooling Earth's surface," wrote Lorraine Rerner with the Joint Center for Earth Systems Technology at the University of Maryland Baltimore County in response to the Weizmann Institute study. (dailycaller.com)
  • The climatic effects of aerosols are complicated by their interactions with clouds," Rerner wrote, adding that the Weizmann study showed "that even small additions of aerosol particles to clouds in the cleanest regions of Earth's atmosphere will have a large effect on those clouds and their contribution to climate forcing. (dailycaller.com)
  • The fresh particles were similar to the cooking organic aerosol over Greek cities during the winter, while the reacted particles were similar to those found in the atmosphere during the summer. (atmos-chem-phys.net)
  • The parameterization reproduces the average diurnal cycle from the observations well for particles sizes up to 0.6 mu m D(p) For larger particles the parameterization tends to over predict the emission velocity. (diva-portal.org)
  • These larger particles are not believed to be produced by combustion and therefore not well represented by F(CO2), which represents the traffic source through its fossil fuel consumption and the related CO(2) emissions. (diva-portal.org)
  • This is surprising, but it appears that in the southeastern U.S. the particles have sufficient water and acidity to preclude them from being the controlling factors in aerosol formation. (phys.org)
  • Aerosol optical properties depend on their atmospheric processing which controls the amount of coating the particles accumulate and their lifetime. (cmu.edu)
  • To assess the effects of coating on the optical properties, we performed targeted experiments using real world, size selected, BC particles emitted from a rocket improved cookstove, and coated with biogenic secondary organic aerosol (SOA) material. (cmu.edu)
  • The primary goal of TERESA is to evaluate the comparative toxicity of secondary particles derived from coal-fired power plant emissions and vehicular sources. (epa.gov)
  • A third, new emission parameterization for fluorescent biological aerosol particles (FBAP) was adapted to field measurements from four locations across Europe. (atmos-chem-phys.net)
  • The results confirm that fungal spores and biological particles may account for a major fraction of supermicron aerosol particle number and mass concentration over vegetated continental regions and should thus be explicitly considered in air quality and climate studies. (atmos-chem-phys.net)
  • precursor
  • The unintended climatic implications of aerosol and precursor emission reductions implemented to protect public health are poorly understood. (nasa.gov)
  • Surprisingly, harmonization of aerosol sources has only a small impact on the simulated diversity for aerosol burden, and consequently optical properties, as the results are largely controlled by model-specific transport, removal, chemistry (leading to the formation of secondary aerosols) and parameterizations of aerosol microphysics (e.g. the split between deposition pathways) and to a lesser extent on the spatial and temporal distributions of the (precursor) emissions. (nasa.gov)
  • cloud conden
  • To unravel the complexity of what drives particle formation, researchers collected data in ambient field studies using advanced aerosol mass spectrometry techniques, in combination with particle into liquid sampler, and cloud condensation nuclei counter, which quantified the aerosol chemical composition and its ability to uptake liquid water. (phys.org)
  • pollutants
  • Cofala J, Amann M, Klimont Z, Kupiainen K, Hölund-Isaksson L (2007) Scenarios of global anthropogenic emissions of air pollutants and methane until 2030. (springer.com)
  • However, to what extent and how exactly human-made pollutants affect aerosol formation from vegetation in the ambient environments are poorly understood. (phys.org)
  • Estimates of Asian emissions of air pollutants and carbonaceous aerosols and their mid-term projections have been changing significantly in the last years. (iiasa.ac.at)
  • trace
  • Two thirds of the OM and oxygen-to-carbon (O/C) measured could be attributed to oil and wood combustion sources on the basis of mild or strong correlations to coemitted, nonvolatile trace metals, with the remaining one third being associated with atmospherically processed organic aerosol. (epfl.ch)
  • biomass
  • Current model treatments of the optical properties of cookstove emissions assume: (1) complete internal mixture between BC and non-BC material and (2) absorption properties of organics based on parametrizations developed for biomass burning emissions. (cmu.edu)
  • fossil fuel
  • When fossil fuel emissions are eliminated or have their sulfate component cleaned up, Earth's rate of heat gain actually increases and quite substantially. (canyoncountryzephyr.com)
  • The global terrestrial carbon sink has increased since the start of this century at a time of growing carbon emissions from fossil fuel burning. (whiterose.ac.uk)
  • Using a combination of models, we estimate that at global scale changes in light regimes from fossil fuel aerosol emissions had only a small negative effect on the increase in terrestrial net primary production over the period 1998-2010. (whiterose.ac.uk)
  • Hereby, the substantial increases in fossil fuel aerosol emissions and plant carbon uptake over East Asia were effectively canceled by opposing trends across Europe and North America. (whiterose.ac.uk)
  • As a result, aerosol loading increased with an increase in fossil fuel consumption in China and other Asian countries and air pollution increased, and thus surface shortwave irradiance decreased. (chikyu.ac.jp)
  • uptake
  • A comprehensive multivariate linear regression analysis showed that sulfate alone, not its associated water uptake or acidity, was responsible for the organic aerosol levels measured. (phys.org)
  • parameterizations
  • The new parameterization results in similar root mean square errors (RMSEs) and correlation coefficients compared to the FBAP observations as the previously existing fungal spore emission parameterizations, with some improvements in the bias. (atmos-chem-phys.net)
  • interactions
  • However, there is a large uncertainty associated with BC's total direct and indirect radiative forcings due to uncertain source emissions and optical properties and complex interactions with clouds. (cmu.edu)
  • radiative
  • To better constrain the large uncertainty of radiative forcing associated with cookstove emissions, this dissertation examines emissions and optical properties from several cookstove and fuel combinations. (cmu.edu)
  • volatile
  • Combining laboratory studies and ambient measurements from multiple sites in and around Atlanta, Georgia, and rural Alabama, scientists found that sulfur dioxide and nitrogen oxides directly and substantially mediate the formation of aerosols from the volatile organic compounds produced by trees. (phys.org)
  • As these gas phase species get oxidized (and become less volatile) they partition into the particle phase as secondary organic aerosol. (colorado.edu)
  • I think the challenge is for gas phase and aerosol scientists to measure and quantify these semi-volatile compounds. (colorado.edu)
  • fraction
  • Greek souvlakia with pork were cooked using a commercial charbroiler and a fraction of the emissions were introduced into a smog chamber where after a characterization phase they were exposed to UV illumination and oxidants. (atmos-chem-phys.net)
  • 0.5) to elemental signatures of oil combustion and 9-24% to wood smoke, indicating that part of the carboxylic acid fraction of OM was formed by the same sources that controlled the metal emissions, namely the oil and wood combustion activities. (epfl.ch)
  • Mass spectral analysis indicated that for periods with similar backward-trajectory-averaged meteorological conditions, air masses influenced by shipping emissions had an increased mass fraction of ions related to carboxylic acids and larger oxygen-to-carbon ratios than those that avoided shipping lanes, suggesting that shipping emissions increase marine organic aerosol (OA) oxidation state. (atmos-chem-phys-discuss.net)
  • sulfate
  • Similarly, "solar radiation management" (deliberate high-altitude sulfate aerosol injection) has also been newly christened as "albedo modification" in another nod to unintended consequences. (canyoncountryzephyr.com)
  • If we are able to further reduce sulfur dioxide and nitrogen oxide emissions, we will not only decrease sulfate aerosols but also organic aerosols , thus lowering the total aerosol burden in the southeast United States," said Nga Lee (Sally) Ng, co-author of the study and assistant professor in Georgia Tech's School of Chemical and Biomolecular Engineering and School of Earth and Atmospheric Sciences. (phys.org)
  • Anthropogenic sulfate, produced mainly by coal-fired power plants, and nitrogen oxides, produced mainly by vehicle emissions, control 43 to 70 percent of the total measured organic aerosol load in the southeastern United States during summer months, the study found. (phys.org)
  • According to the study, the formation of aerosols from certain tree emissions is directly controlled by the abundance of sulfate, instead of particle water or particle acidity as suggested by prior studies. (phys.org)
  • Based on estimated methanesulfonic acid (MSA) mass loadings and published biogenic MSA to non-sea-salt-sulfate (nss-SO 4 ) ratios, an average of over 75 % of the observed nss-SO 4 was from anthropogenic sources, predominantly shipping emissions. (atmos-chem-phys-discuss.net)
  • increases
  • Nationally averaged increases in all of those extreme precipitation indices above due to the aerosol reduction account for more than 30 % of the extreme precipitation increases under the RCP8.5 scenario. (springer.com)
  • Global and regional precipitation mostly increases when we reduce regional aerosol emissions in the models, with the strongest responses occurring for sulfur dioxide emissions reductions from Europe and the United States. (nasa.gov)
  • Precipitation increases in the Sahel in response to aerosol reductions in remote regions because an anomalous interhemispheric temperature gradient alters the position of the Intertropical Convergence Zone (ITCZ). (nasa.gov)
  • The economic development in the East Asian countries led by the industrialization brought increases in energy consumption and emissions of CO2, SO2 and others. (chikyu.ac.jp)
  • impacts
  • But fully adding the effects of cloud cover into their climate models could force scientists to reconsider temperature impacts from greenhouse gas emissions. (dailycaller.com)
  • Recently, both of these energy sources are undergoing rapid technology changes, and the climate impacts from the emissions of these newly adopted technologies remain uncertain. (cmu.edu)
  • This dissertation first assesses the climate impacts of aerosol emissions of two rapidly emerging technologies: improved cookstoves and gasoline direct injection (GDI) vehicles. (cmu.edu)
  • Of all the stoves tested, charcoal stoves had the lowest emissions and climate impacts. (cmu.edu)
  • We aim to relate the sensitivity of changes in (1) - (3) to their dominant climate, emission, and land use impacts to help provide insight into beneficial air quality management and mitigation strategies in the future. (epa.gov)
  • laboratory
  • In this study, we provide a method to constrain the BrC absorptivity at the emission inventory level using recent laboratory and field observations. (osti.gov)
  • In contrast, the ambient COA factor during winter resembled strongly the fresh laboratory meat charbroiling emissions. (atmos-chem-phys.net)
  • This study also used the Georgia Tech Environmental Chamber Facility to investigate aerosol formation and chemical composition under nighttime conditions in a well-controlled laboratory setting, which was supported by an EPA Early Career Award Ng received. (phys.org)
  • We performed extensive laboratory measurements of the optical properties of fresh cookstove emissions using the newly developed firepower sweep protocol. (cmu.edu)
  • One of the higher yield types of species (as measured in the laboratory) from anthropogenic emissions is toluene and other aromatic hydrocarbons (referred to as high yield aromatics). (colorado.edu)
  • An equation modeling ir aerosol emission is presented with experimental data and spectra of low temperature steam from laboratory radiometric measurements. (osapublishing.org)
  • We conducted combustion experiments in the laboratory to investigate the emission ratio and mixing state of rBC from the burning of wheat straw and rapeseed plants, which are the main crops cultivated in the Yangtze River Delta region of China. (atmos-chem-phys.net)
  • This study performed laboratory experiments: we found that emission of rBC is highly related to flaming burning, and non-rBC to smoldering burning. (atmos-chem-phys.net)
  • fluxes
  • Size-resolved aerosol vertical number fluxes were measured using the eddy covariance method, 105 meters above the ground over the city of Stockholm, Sweden, between 1st April 2008 and 15th April 2009. (diva-portal.org)
  • The experiment also indicated that despite prescribing emission fluxes and size distributions, ambiguities in the implementation in individual models can lead to substantial differences. (nasa.gov)
  • burden
  • Based on CAM-Oslo global climate model output, no straight-forward relationship was found between the change in the number emissions and changes in the sea salt aerosol burden or optical thickness. (diva-portal.org)
  • meteorology
  • E&E News reported the researchers "used data from four different satellites to observe the clouds, the aerosol content, temperature, meteorology and rainfall over 92 days in the winter of 2007. (dailycaller.com)
  • meteorological
  • The magnitude of the emissions estimated with MEGAN2.1 are within the range of estimates reported using other approaches and much of the differences between reported values can be attributed to land cover and meteorological driving variables. (geosci-model-dev.net)
  • The implication is that a substantial part of the measured carboxylic acid contribution was formed independently of traditionally 'secondary' processes, which would be affected by atmospheric (both photochemical and meteorological) conditions and other emission sources. (epfl.ch)
  • clouds
  • The idea is that few clouds may have populated the skies before the Industrial Revolution, but the increased aerosol emissions from man-made industrial sources may have actually increased cloud cover on the planet and caused a cooling effect. (dailycaller.com)
  • As the aerosol levels in the clouds increased naturally, the more overcast the region became, and the more it cooled. (dailycaller.com)
  • The authors also found that "there was no point of saturation beyond which aerosols stopped affecting the clouds. (dailycaller.com)
  • Aerosols, natural or man-made, are key to creating cloud cover, without them there would be no clouds. (dailycaller.com)
  • Ultimately, it [aerosols] affects the amount of clouds that are out there, and also the properties of the clouds - the area, for example, they cover over the globe. (dailycaller.com)
  • combustion
  • Alcohol groups accounted for 14% of OM (mostly associated with oil combustion emissions and background sources), and amine groups accounted for 4% of OM in all air masses. (epfl.ch)