Light absorption of brown carbon in eastern China based on 3-year multi-wavelength aerosol optical property observations and an improved absorption Ångström exponent segregation method

Wang, Jiaping; Nie, Wei; Cheng, Yafang; Shen, Yicheng; Chi, Xuguang; Wang, Jiandong; Huang, Xin; Xie, Yue; Sun, Peng; Xu, Zheng; Qi, Ximeng; Su, Hang; Ding, Aijun

doi:10.5194/acp-18-9061-2018

Cited by 88 publications

(63 citation statements)

References 70 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The average concentration of levoglucosan in PM 2.5 was 373 ± 268 ng m −3 in this study, which was significantly higher than those observed at the coastal sites in Europe (Puxbaum et al, 2007;von Schneidemesser et al, 2009), the forest sites in the eastern China (W. Wang et al, 2008) and some rural sites in Canada and Hong Kong (Leithead et al, 2006;Sang et al, 2011). But for the rural sites of Australia, levoglucosan was found to be much more enriched than in this study (Reisen et al, 2011).…”

Section: Biomass Burning Tracerscontrasting

confidence: 78%

Chemical and optical properties of carbonaceous aerosols in Nanjing, eastern China: regionally transported biomass burning contribution

et al. 2019

View full text Add to dashboard Cite

Abstract. Biomass burning can significantly impact the chemical and optical properties of carbonaceous aerosols. Here, the biomass burning impacts were studied during wintertime in a megacity of Nanjing, eastern China. The high abundance of biomass burning tracers such as levoglucosan (lev), mannosan (man), galactosan (gal) and non-sea-salt potassium (nss-K+) was found during the studied period with the concentration ranges of 22.4–1476 ng m−3, 2.1–56.2 ng m−3, 1.4–32.2 ng m−3 and 0.2–3.8 µg m−3, respectively. The significant contribution of biomass burning to water-soluble organic carbon (WSOC; 22.3±9.9 %) and organic carbon (OC; 20.9±9.3 %) was observed in this study. Backward air mass origin analysis, potential emission sensitivity of elemental carbon (EC) and MODIS fire spot information indicated that the elevations of the carbonaceous aerosols were due to the transported biomass-burning aerosols from southeastern China. The characteristic mass ratio maps of lev∕man and lev∕nss-K+ suggested that the biomass fuels were mainly crop residuals. Furthermore, the strong correlation (p < 0.01) between biomass burning tracers (such as lev) and light absorption coefficient (babs) for water-soluble brown carbon (BrC) revealed that biomass burning emissions played a significant role in the light-absorption properties of carbonaceous aerosols. The solar energy absorption due to water-soluble brown carbon and EC was estimated by a calculation based on measured light-absorbing parameters and a simulation based on a radiative transfer model (RRTMG_SW). The solar energy absorption of water-soluble BrC in short wavelengths (300–400 nm) was 0.8±0.4 (0.2–2.3) W m−2 (figures in parentheses represent the variation range of each parameter) from the calculation and 1.2±0.5 (0.3–1.9) W m−2 from the RRTMG_SW model. The absorption capacity of water-soluble BrC accounted for about 20 %–30 % of the total absorption of EC aerosols. The solar energy absorption of water-soluble BrC due to biomass burning was estimated as 0.2±0.1 (0.0–0.9) W m−2, considering the biomass burning contribution to carbonaceous aerosols. Potential source contribution function model simulations showed that the solar energy absorption induced by water-soluble BrC and EC aerosols was mostly due to the regionally transported carbonaceous aerosols from source regions such as southeastern China. Our results illustrate the importance of the absorbing water-soluble brown carbon aerosols in trapping additional solar energy in the low-level atmosphere, heating the surface and inhibiting the energy from escaping the atmosphere.

show abstract

Section: Biomass Burning Tracerscontrasting

confidence: 78%

Chemical and optical properties of carbonaceous aerosols in Nanjing, eastern China: regionally transported biomass burning contribution

et al. 2019

View full text Add to dashboard Cite

show abstract

“…polycyclic aromatic hydrocarbons (PAHs) (Chen et al, 2017b;Zhang et al, 2008). Based on Ebenstein et al 2017 The light-absorbing particles (i.e., BC and BrC) have been proved to reduce solar radiation reaching the ground and further influence regional climate and crop production (Alexander et al, 2008;Bond et al, 2013;Tie et al, 2016;Wang et al, 2018). This study shows that concentrations of BC (i.e., EC or soot) were low at 2.7-4.3 μg/m 3 during the haze days and only accounted for 1.4-3.9% of PM2.5 in Northeast China (Figures 2a-c).…”

Section: Atmospheric Implicationsmentioning

confidence: 99%

Exploring wintertime regional haze in Northeast China: role of coal and biomass burning

Zhang¹,

Liu²,

Li³

et al. 2020

Preprint

View full text Add to dashboard Cite

Abstract. As one of the intense anthropogenic emission regions across the relatively high latitude (>&#8201;40&#176;&#8201;N) areas on the Earth, Northeast China faces serious problem on regional haze during long winter with half a year. Aerosols in polluted haze in Northeast China are poorly understood compared with the haze in other regions of China such as North China Plain. Here, we for the first time integrated bulk chemical measurements with single particle analysis from transmission electron microscopy (TEM), nanoscale secondary ion mass spectrometer (NanoSIMS), and atomic force microscopy (AFM) to obtain morphology, size, composition, aging process, and sources of aerosol particles collected during two contrasting regional haze events (Haze-I and Haze-II) at an urban site and a mountain site in Northeast China, and further investigated the causes of regional haze formation. Haze-I evolved from moderate (average PM2.5: 76&#8211;108&#8201;&#956;g/m3) to heavy pollution (151&#8211;154&#8201;&#956;g/m3), with the dominant PM2.5 component changing from organic matter (OM) (39&#8211;45&#8201;&#956;g/m3) to secondary inorganic ions (94&#8211;101&#8201;&#956;g/m3). Similarly, TEM observations showed that S-OM particles elevated from 29&#8201;% to 60&#8201;% by number at urban site and 64&#8201;% to 74&#8201;% at mountain site and 75&#8211;96&#8201;% of Haze-I particles included primary OM. Change of wind direction induced that Haze-I rapidly turned into Haze-II (185&#8211;223&#8201;&#956;g/m3) with the predominant OM (98&#8211;133&#8201;&#956;g/m3) and unexpectedly high K+ (3.8&#8201;&#956;g/m3). TEM also showed that K-OM particles increased from 4&#8211;5&#8201;% by number to 50&#8211;52&#8201;%. Our study revealed a contrasting formation mechanism of these two haze events: Haze-I was induced by accumulation of primary OM emitted from residential coal burning and further deteriorated by secondary aerosol formation via heterogeneous reactions; Haze-II was caused by long-range transport of agricultural biomass burning emissions. Moreover, we found that 75&#8211;97&#8201;% of haze particles contained tarballs, but only 4&#8211;23&#8201;% contained black carbon and its concentrations were low at 2.7&#8211;4.3&#8201;&#956;g/m3. The results highlight that abundant tarballs are important light-absorbing brown carbon in Northeast China during winter haze and further considered in climate models.

show abstract

“…However, studies have demonstrated that AAE BC can be affected by the refractive index of coating materials, mixing state, morphology, and BC core size (Liu et al, 2015). Moreover, different values of AAE BC have been found in the NIR and UV ranges (Wang et al, 2018). Therefore, using the default AAE BC = 1 may lead to uncertainty in BrC absorption estimation.…”

Section: Estimation Of Aae Bcmentioning

confidence: 99%

“…The lensing effect of the coating shell may enhance BC light absorption, the magnitude of which may also depend on wavelength and can alter the value of AAE BC . Moreover, different values of AAE BC have been found in the NIR and UV ranges (Wang et al, 2018). Therefore, using the default AAE BC = 1 may lead to uncertainty in BrC absorption coefficient estimation.…”

Section: Introductionmentioning

confidence: 99%

Light absorption property and potential source of particulate brown carbon in the Pearl River Delta region of China

Li¹,

Tan²,

Zheng³

et al. 2019

Preprint

View full text Add to dashboard Cite

Abstract. Brown carbon (BrC) is a type of light-absorbing component of organic aerosol (OA), covering from near-ultraviolet (UV) to visible wavelength ranges, and thus may cause additional aerosol radiative effect in the atmosphere. While high concentrations of OA have been observed in the Pearl River Delta (PRD) region of China, optical properties and the corresponding radiative forcing of BrC in PRD are still not well understood. In this work, we conducted a set of comprehensive measurements of atmospheric particulate matters from 29 November 2014 to 5 January 2015 to investigate aerosol composition, optical properties, source origins and radiative forcing effects at a suburban station of Guangzhou. Particle absorption &#197;ngstr&#246;m exponent (AAE) was deduced and utilized to differentiate light absorption by BrC from black carbon (BC). The results showed that the average absorption contributions of BrC were 25.9&#8201;&#177;&#8201;9.0&#8201;% at 370&#8201;nm, 19.7&#8201;&#177;&#8201;7.9&#8201;% at 470&#8201;nm, 14.1&#8201;&#177;&#8201;6.9&#8201;% at 520&#8201;nm, 11.6&#8201;&#177;&#8201;5.6&#8201;% at 590&#8201;nm and 7.7&#8201;&#177;&#8201;4.4&#8201;% at 660&#8201;nm, respectively. A sensitivity analysis of the evaluation of absorption &#197;ngstr&#246;m exponent of BC (AAEBC) was conducted based on the Mie theory calculation, assuming that the BC-containing aerosol was internally mixed, with a core-shell configuration. The corresponding uncertainty of BrC absorption contribution was acquired. We found that variations in the imaginary refractive index (RI) of BC core can significantly affect the estimation of BrC absorption contribution. However, BrC absorption contribution was relatively less sensitive to the real part of RI of BC core and was least sensitive to the real part of RI of non-light absorbing shell. BrC absorption was closely related to aerosol potassium cation content (K+), a common tracer of biomass burning emission, which was most likely associated with straw burning in the rural area of western PRD. Diurnal variation of BrC absorption revealed that primary organic aerosol had a larger BrC absorption capacity than secondary organic aerosol (SOA) had. Radiative transfer simulations showed that BrC absorption may cause 2.2&#8201;&#177;&#8201;2.3&#8201;W&#8201;m&#8722;2 radiative forcing at the top of atmosphere (TOA) and contribute 14.2&#8201;&#177;&#8201;6.2&#8201;% of the aerosol warming effect. A chart was constructed to conveniently assess the BrC radiative forcing efficiency in the studied area with reference to a certain aerosol single-scattering albedo (SSA) and BrC absorption contribution at various wavelengths. Evidently, BrC radiative forcing efficiency was higher in shorter wavelength.

show abstract

Light absorption of brown carbon in eastern China based on 3-year multi-wavelength aerosol optical property observations and an improved absorption Ångström exponent segregation method

Cited by 88 publications

References 70 publications

Chemical and optical properties of carbonaceous aerosols in Nanjing, eastern China: regionally transported biomass burning contribution

Chemical and optical properties of carbonaceous aerosols in Nanjing, eastern China: regionally transported biomass burning contribution

Exploring wintertime regional haze in Northeast China: role of coal and biomass burning

Light absorption property and potential source of particulate brown carbon in the Pearl River Delta region of China

Contact Info

Product

Resources

About