Sentences with phrase «as organic aerosols»

They are known as organic aerosols, or OA.

Not exact matches

Photo credit: DRIChakrabarty and colleagues found to their surprise that funeral pyre emissions contain sunlight - absorbing organic carbon aerosols known as brown carbon.

Yet, the factors that influence the formation of these aerosols, known as secondary organic aerosol or SOA, are often assumed.

Even though open windows bring in more ozone from outside, the reduction in the indoor limonene concentration and SOA formation strength more than make up for it, as less secondary organic aerosol is formed inside.

This includes the role of oxidized volatile organic compounds, such as limonene and alpha - pinene, the typical scents of the citrus fruits and coniferous forests, in aerosol formation.

In research recently published in Environmental Science & Technology, Waring describes the role of limonene, the organic compound that gives cleaners and air fresheners an orange scent and acts as a solvent, in the formation of secondary organic aerosols.

By adjusting elements of the test, such as the air exchange rate, which is the number of times per hour indoor air is replaced by outdoor air, as well as the concentrations of terpene and ozone in the chamber, the group was able to ascertain how those variables each affected the formation of secondary organic aerosols.

, Kilcoyne, A.L.D., Moffet, R.C., Weigand, M., Martin, S.T., Pöschl, U., and Andreae, M.O.: Biogenic potassium salt particles as seeds for secondary organic aerosol in the Amazon, Science, 337, 1075 - 1078, 2012.

Further investigation showed that Titan's atmosphere has organic aerosols, called tholins, that likely formed from molecules such as methane and nitrogen.

The specialized instruments onboard the aircraft sampled the plume for aerosol particle size distribution and composition as well as concentrations of pollutant gases such as sulfur dioxide, nitric oxide, nitrogen dioxide, ozone, and volatile organic compounds (VOCs).

These oligomers are also the starting materials for troubling atmospheric aerosols, known as secondary organic aerosols.

The team evaluated simulated cloud fields from the multi-scale aerosol - climate model and examined how specific human - caused aerosols, such as sulfate, black carbon (soot), and organic carbon affect those clouds and, in turn, the climate.

The team injected citric, adipic, and fulvic acid into the chamber as seed aerosols, and then introduced a secondary organic aerosol from α - pinene, a carbon - containing compound derived from pine trees.

The largest portion of these submicron aerosols is organic, or carbon - containing, and is classified as two kinds: primary and secondary.

Results: Today's climate models regard organic aerosols as static carbon - based molecules, but scientists at Pacific Northwest National Laboratory and the University of California, Irvine showed that the particles are very dynamic.

Her research experience includes modeling of organic aerosol oxidation at LBNL, fabrication and optimization of high performance semiconductor nanoparticle - based image sensors as Manager of Materials Development at InVisage Technologies, Inc., and foundational and applied research as a Research Staff Member at IBM's Almaden Research Center on transformations in dielectrics, semiconductors, metals, and polymer films.

Aside from aerosol solutions, and ocean clouds a la Latham and Salter, I think an essential will be capturing waste organics (mostly farm debris, corn stalks etc.) and sequestering them in the deep ocean (not as CO2; just drop bales; much cheaper and efficient).

Importantly, RCP4.5 considers the influence of sulfur aerosols, as well as black and organic carbon.

Brown clouds contain dark aerosols such as soot that are released into the atmosphere by burning organic matter.

The brownish color of the cloud (which is visible when looking at the horizon) is due to absorption of solar radiation at short wavelengths (green, blue, and UV) by organic and black carbon aerosols as well as by NOx.

New evidence shows that the ocean also acts as a source of organic matter from biogenic origin -LSB-...] Surface - active organic matter of biogenic origin -LSB-...] enriched in the oceanic surface layer and transferred to the atmosphere by bubble - bursting processes, are the most likely candidates to contribute to the observed organic fraction in marine aerosol.

It delves into the impacts of aerosols, which are tiny pollutants of mineral dust, soot and organic matter emitted by sources such as power plants, factories and quarries.

Increased biomass can lead to increased emissions of biogases such as dimethyl sulfide and isoprene, which when oxidized in the atmospheric form sulphate and organic aerosols that can nucleate clouds, increasing cloud cover and planetary albedo — the CLAW Hypothesis.

These NCA emissions directly affect particle concentrations and human exposure to nanosized aerosol in urban areas, and potentially may act as nanosized condensation nuclei for the condensation of atmospheric low - volatile organic compounds.

Aerosol «blue haze», as seen here in the Great Smoky Mountains in North Carolina, is formed by the oxidation of volatile organic compounds emitted by trees.

Organic aerosols that are directly injected in the atmosphere in the particulate phase are called primary organic aerosols (POA), while those that are created by the oxidation of volatile organic compounds are known as secondary organic aerosols (SOA).

At left, the composite annual mean organic aerosol surface air concentrations of the models, defined as the median of the model fields on a 5 ° × 5 ° grid.

In densely populated areas however, anthropogenically generated and released hydrocarbons play an important role as precursor of the development of secondary organic aerosols.

PNNL scientists found that secondary organic aerosols formed in the presence of the toxic pollutant known as polycyclic aromatic hydrocarbons (PAHs) trapped the PAH molecules inside, shielding them from degradation.

This thinning, which can decrease the ozone concentration by as much as 70 percent, was caused by the rampant use of human - made chlorofluorocarbons (CFCs), organic compounds that were once widely used in cooling systems and aerosols.

First, we have to consider the effect of aerosols, which start off as urban haze or rural smoke and ultimately become transcontinental and transoceanic plumes o ABCs consisting of sulfate, nitrate, hundreds of organics, black carbon, soil dust, fly ash, and other aerosols.

The climate feedbacks involved with these changes, which are key in understanding the climate system as a whole, include: + the importance of aerosol absorption on climate + the impact of aerosol deposition which affects biology and, hence, emissions of aerosols and aerosol precursors via organic nitrogen, organic phosphorus and iron fertilization + the importance of land use and land use changes on natural and anthropogenic aerosol sources + the SOA sources and impact on climate, with special attention on the impact human activities have on natural SOA formation In order to quantitatively answer such questions I perform simulations of the past, present and future atmospheres, and make comparisons with measurements and remote sensing data, all of which help understand, evaluate and improve the model's parameterizations and performance, and our understanding of the Earth system.

My studies range from detailed aerosol processes such as the formation of secondary organic aerosols (SOA), to centennial time scale climate variability related to natural variability and external forcings.

Topics that I work on or plan to work in the future include studies of: + missing aerosol species and sources, such as the primary oceanic aerosols and their importance on the remote marine atmosphere, the in - cloud and aerosol water aqueous formation of organic aerosols that can lead to brown carbon formation, the primary terrestrial biological particles, and the organic nitrogen + missing aerosol parameterizations, such as the effect of aerosol mixing on cloud condensation nuclei and aerosol absorption, the semi-volatility of primary organic aerosols, the importance of in - canopy processes on natural terrestrial aerosol and aerosol precursor sources, and the mineral dust iron solubility and bioavailability + the change of aerosol burden and its spatiotemporal distribution, especially with regard to its role and importance on gas - phase chemistry via photolysis rates changes and heterogeneous reactions in the atmosphere, as well as their effect on key gas - phase species like ozone + the physical and optical properties of aerosols, which affect aerosol transport, lifetime, and light scattering and absorption, with the latter being very sensitive to the vertical distribution of absorbing aerosols + aerosol - cloud interactions, which include cloud activation, the aerosol indirect effect and the impact of clouds on aerosol removal + changes on climate and feedbacks related with all these topics In order to understand the climate system as a whole, improve the aerosol representation in the GISS ModelE2 and contribute to future IPCC climate change assessments and CMIP activities, I am also interested in understanding the importance of natural and anthropogenic aerosol changes in the atmosphere on the terrestrial biosphere, the ocean and climate.

For a comprehensive GCM I can count oceans, land, atmosphere, ice, biological processes, organic and inorganic chemical processes, human - made sources and other effects, radiative energy transport, conduction and convective heat transfer, phase change, clouds and aerosols, as some of the important system components, phenomena, and processes.

However, coatings of organic carbon aerosol on hygroscopic aerosol such as sulphate may lead to suppression of the rate of water uptake during cloud activation (Xiong et al., 1998; Chuang, 2003).

Theoretically, coatings of essentially non-absorbing components such as organic carbon or sulphate on strongly absorbing core components such as black carbon can increase the absorption of the composite aerosol (e.g., Fuller et al., 1999; Jacobson, 2001a; Stier et al., 2006a), with results backed up by laboratory studies (e.g., Schnaiter et al., 2003).

Observational evidence suggests that some organic aerosol compounds from fossil fuels are relatively weakly absorbing but do absorb solar radiation at some ultraviolet and visible wavelengths (e.g., Bond et al., 1999; Jacobson, 1999; Bond, 2001) although organic aerosol from high - temperature combustion such as fossil fuel burning (Dubovik et al., 1998; Kirchstetter et al., 2004) appears less absorbing than from low - temperature combustion such as open biomass burning.

Organic aerosols are emitted as primary aerosol particles or formed as secondary aerosol particles from condensation of organic gases considered semi-volatile or having low volatility.

However, sulphate is invariably internally and externally mixed to varying degrees with other compounds such as biomass burning aerosol (e.g., Formenti et al., 2003), fossil fuel black carbon (e.g., Russell and Heintzenberg, 2000), organic carbon (Novakov et al., 1997; Brock et al., 2004), mineral dust (e.g., Huebert et al., 2003) and nitrate aerosol (e.g., Schaap et al., 2004).