Effect of intrinsic organic carbon on the optical properties of fresh diesel soot

Adler, Gabriella; Riziq, A. Abo; Erlick, Carynelisa; Rudich, Yinon

doi:10.1073/pnas.0903311106

Cited by 125 publications

(149 citation statements)

References 49 publications

Supporting

Mentioning

140

Contrasting

Unclassified

Order By: Relevance

“…If we assume that coating by non-or weakly-absorbing aerosol results in a ∼35 % enhancement then our reduced MAE value of 7.0 +/ 0.6 m 2 g −1 at 530 nm is in good agreement with the value of 7.5±0.3 m 2 g −1 (@550 nm) reported for BC in the review by Bond et al (2006) and 7.1 m 2 g −1 recently reported for diesel soot (Adler et al, 2010). If absorption by uncoated BC is being over estimated by 80 % then a reduced value of ∼5.3 m 2 g −1 is comparable to Fuller et al (1999) who reported an MAE value of 5.4 m 2 g −1 for amorphous graphitic spheres from diesel soot.…”

Section: Mass Absorption Efficiency Of Light Absorbing Carbonsupporting

confidence: 80%

Absorbing aerosol in the troposphere of the Western Arctic during the 2008 ARCTAS/ARCPAC airborne field campaigns

et al. 2011

View full text Add to dashboard Cite

Abstract. In the spring of 2008 NASA and NOAA funded the ARCTAS and ARCPAC field campaigns as contributions to POLARCAT, a core IPY activity. During the campaigns the NASA DC-8, P-3B and NOAA WP-3D aircraft conducted over 160 h of in-situ sampling between 0.1 and 12 km throughout the Western Arctic north of 55 • N (i.e. Alaska to Greenland). All aircraft were equipped with multiple wavelength measurements of aerosol optics, trace gas and aerosol chemistry measurements, as well as direct measurements of the aerosol size distributions and black carbon mass. Late April of 2008 proved to be exceptional in terms of Asian biomass burning emissions transported to the Western Arctic. Though these smoke plumes account for only 11-14 % of the samples within the Western Arctic domain, they account for 42-47 % of the total burden of black carbon. Dust was also commonly observed but only contributes to 4-12 % and 3-8 % of total light absorption at 470 and 530 nm wavelengths above 6 km. Below 6 km, light absorption by carbonaceous aerosol derived from urban/industrial and biomass burning emissions account for 97-99 % of total light absorption by aerosol. Stratifying the data to reduce the influence of dust allows us to determine mass absorption efficiencies for black carbon of 11.2±0.8, 9.5±0.6 and 7.4±0.7 m 2 g −1 at 470, 530 and 660 nm waveCorrespondence to: C. S. McNaughton (csmcnaug@hawaii.edu) lengths. These estimates are consistent with 35-80 % enhancements in 530 nm absorption due to clear or slightly absorbing coatings of pure black carbon particulate. Assuming a 1/λ wavelength dependence for BC absorption, and assuming that refractory aerosol (420 • C, τ = 0.1 s) in lowdust samples is dominated by brown carbon, we derive mass absorption efficiencies for brown carbon of 0.83±0.15 and 0.27±0.08 m 2 g −1 at 470 and 530 nm wavelengths. Estimates for the mass absorption efficiencies of Asian dust are 0.034 m 2 g −1 and 0.017 m 2 g −1 . However the absorption efficiency estimates for dust are highly uncertain due to the limitations imposed by PSAP instrument noise. In-situ ARC-TAS/ARCPAC measurements during the IPY provide valuable constraints for absorbing aerosol over the Western Arctic, species which are currently poorly simulated over a region that is critically under-sampled.

show abstract

Section: Mass Absorption Efficiency Of Light Absorbing Carbonsupporting

confidence: 80%

Absorbing aerosol in the troposphere of the Western Arctic during the 2008 ARCTAS/ARCPAC airborne field campaigns

et al. 2011

View full text Add to dashboard Cite

show abstract

“…From the climate change point of view, reductions in EC aerosol emissions could reduce the positive radiative forcing effect associated with diesel PM emissions (Gaffney and Marley 2009), and since OC aerosol species tend to have a negative radiative forcing effect (Adler et al 2009) their warming effect might as well be reduced. In regards to OC aerosol emissions, there was little variation for B25, B50, and B75 blends, however, using pure biodiesel fuel (B100) resulted in increases in overall OC aerosol emission rates, mostly associated with unburned fatty acid methyl esters.…”

Section: Discussionmentioning

confidence: 99%

Sensitivity of Diesel Particulate Material Emissions and Composition to Blends of Petroleum Diesel and Biodiesel Fuel

Magara-Gomez

Olson

Okuda

et al. 2012

Aerosol Science and Technology

View full text Add to dashboard Cite

A number of investigations have examined the impact of the use of biodiesel on the emissions of carbon dioxide and regulated emissions, but limited information exists on the chemical composition of particulate matter from diesel engines burning biodiesel blends. This study examines the composition of diesel particulate matter (DPM) emissions from a commercial agriculture tractor burning a range of biodiesel blends operating under a load that is controlled by a power take off (PTO) dynamometer. Ultra-low sulfur diesel (ULSD) fuel was blended with soybean and beef tallow based biodiesel to examine fuels containing 0% (B0), 25% (B25), 50% (B50), 75% (B75), and 100% (B100) biodiesel. Samples were then collected using a dilution source sampler to simulate atmospheric dilution. Diluted and aged exhaust was analyzed for particle mass and size distribution, PM 2.5 particle mass, PM 2.5 organic and elemental carbon, and speciated organic compounds. PM 2.5 mass emissions rates for the B25, B50, and B75 soybean oil biodiesel mixtures had 20%-30% lower emissions than the petroleum diesel, but B100 emissions were about 40% higher than the petroleum diesel. The trends in mass emission rates with the increasing biodiesel content can be explained by a significant decrease in elemental carbon (EC) emissions across all blending ranges and increasing organic carbon (OC) emissions with pure biodiesel. Beef tallow biodiesel blends showed similar trends. Nevertheless, it is important to note that the study measurements are based on low dilution rates and the OC emissions changes may be affected by ambient temperature and different dilution conditions spanning microenvironments and atmospheric conditions. The results show that the use of biodiesel fuel for economic or climate change mitigation

show abstract

“…Both laser powers give a collection efficiency of over 80% for rBC mass >0.2fg. Considering that the size of primary spherules of soot are 30-50nm 28 , equivalent to D ve in the range 0.02-0.1fg, this SP2 detection efficiency is sufficient to measure the small rBC.…”

Section: Figure Captionsmentioning

confidence: 99%

Black-carbon absorption enhancement in the atmosphere determined by particle mixing state

et al. 2017

View full text Add to dashboard Cite

Atmospheric black carbon makes an important but poorly quantified contribution to the warming of the global atmosphere. Laboratory and modelling studies have shown that the addition of non-black carbon materials to black carbon particles may enhance the particles' light absorption by 50 to 60% by refracting and reflecting light. Real world experimental evidence for this 'lensing' effect is scant and conflicting, showing that absorption enhancements can be less than 5% or as large as 140%. Here we present simultaneous quantifications of the composition and optical properties of individual atmospheric black carbon particles. We show that particles with a mass ratio of non-black carbon to black carbon of less than 1.5, which is typical of fresh traffic sources, are best represented as having no absorption enhancement. In contrast, black carbon particles with a ratio greater than 3, which is typical of biomass burning emissions, are best described assuming optical lensing leading to an absorption enhancement. We introduce a generalised hybrid model approach for estimating scattering and absorption enhancements based on laboratory and atmospheric observations. We conclude that the occurrence of the absorption enhancement of black carbon particles is determined by the particles' mass ratio of non-black carbon to black carbon.Atmospheric black carbon (BC) makes the second largest single contribution after CO 2 to climate forcing in the present-day atmosphere 1 . Previous detailed modelling and laboratory studies have shown that weakly absorbing non-BC materials contained within the same particles as BC can significantly enhance the absorption per unit mass of the latter through refraction and internal reflections, sometimes referred to as the 'lensing effect' 2,3 . A "coreshell" description 4 has often been applied to describe this effect when coatings envelop the central BC core, but this oversimplifies the complex particle morphologies 5 . The non-BC components may not be evenly distributed and the BC core is not necessarily completely enclosed, and as such the absorption enhancement predicted using the core-shell approach could greatly overestimate the real value 3 . Microscopy 5,6 can examine BC microphysical properties but has limited quantitative capability and may evaporate semi-volatile materials.By detecting the remaining non-BC fragment after laser induced incandescence with a single particle soot photometer (SP2 7 , DMT inc.), Sedlacek et al. 8 and Moteki et al. 9 reported the non-core-shell structure of some BC particles, however they did not provide an appropriate model approach to estimate optical properties. Measurement of single BC particle mass ratioIn this study, for the first time we quantify the mixing state of individual BC particles using morphology-independent measurements of the total particle mass (M p ) and the mass of the refractory black carbon, rBC (M rBC ) from a variety of laboratory and field experiments. We determined the mass ratio, M R (= M non-BC /M rBC ), where M non-BC is the mas...

show abstract

Effect of intrinsic organic carbon on the optical properties of fresh diesel soot

Cited by 125 publications

References 49 publications

Absorbing aerosol in the troposphere of the Western Arctic during the 2008 ARCTAS/ARCPAC airborne field campaigns

Absorbing aerosol in the troposphere of the Western Arctic during the 2008 ARCTAS/ARCPAC airborne field campaigns

Sensitivity of Diesel Particulate Material Emissions and Composition to Blends of Petroleum Diesel and Biodiesel Fuel

Black-carbon absorption enhancement in the atmosphere determined by particle mixing state

Contact Info

Product

Resources

About