Evaluation of the global oceanic isoprene source and its impacts on  marine organic carbon aerosol

Abstract. We have combined the first satellite maps of the global distribution of phytoplankton functional type and new measurements of phytoplankton-specific isoprene productivities, with available remote marine isoprene observations and a global model, to evaluate our understanding of the marine isoprene source and its impacts on organic aerosol abundances. Using satellite products to scale up data on phytoplankton-specific isoprene productivity to the global oceans, we infer a mean "bottom-up" oceanic isoprene emission of 0.31±0.08 (1σ) Tg/yr. By minimising the mean bias between the model and isoprene observations in the marine atmosphere remote from the continents, we produce a "top-down" oceanic isoprene source estimate of 1.9 Tg/yr. We suggest our reliance on limited atmospheric isoprene data, difficulties in simulating in-situ isoprene production rates in laboratory phytoplankton cultures, and limited knowledge of isoprene production mechanisms across the broad range of phytoplankton communities in the oceans under different environmental conditions as contributors to this difference between the two estimates. Inclusion of secondary organic aerosol (SOA) production from oceanic isoprene in the model with a 2% yield produces small contributions (0.01–1.4%) to observed organic carbon (OC) aerosol mass at three remote marine sites in the Northern and Southern Hemispheres. Based on these findings we suggest an insignificant role for isoprene in modulating remote marine aerosol abundances, giving further support to a recently postulated primary OC source in the remote marine atmosphere.

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Evaluation of the global oceanic isoprene source and its impacts on marine organic carbon aerosol

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-8-16445-2008 ◽

2008 ◽

Vol 8 (4) ◽

pp. 16445-16471 ◽

Cited By ~ 4

Author(s):

S. R. Arnold ◽

D. V. Spracklen ◽

J. Williams ◽

N. Yassaa ◽

J. Sciare ◽

...

Keyword(s):

Organic Carbon ◽

Scale Up ◽

Organic Aerosol ◽

Marine Atmosphere ◽

Marine Aerosol ◽

Aerosol Mass ◽

Phytoplankton Communities ◽

The Mean ◽

Global Oceans ◽

Northern And Southern Hemispheres

Abstract. We have combined the first satellite maps of the global distribution of phytoplankton functional type and new measurements of phytoplankton-specific isoprene productivities, with available remote marine isoprene observations and a global model, to evaluate our understanding of the marine isoprene source and its impacts on organic aerosol abundances. Using satellite products to scale up data on phytoplankton-specific isoprene productivity to the global oceans, we infer a mean "bottom-up" oceanic isoprene emission of 0.31±0.08 (1 σ) Tg/yr. By minimising the mean bias between the model and isoprene observations in the marine atmosphere remote from the continents, we produce a "top-down" oceanic isoprene source estimate of 1.9 Tg/yr. We suggest our reliance on limited atmospheric isoprene data, and limited knowledge of isoprene productivity across the broad range of phytoplankton communities in the oceans as contributors to this difference between the two estimates. Inclusion of secondary organic aerosol (SOA) production from oceanic isoprene in the model with a 2% yield produces small contributions (0.01–1.6%) to observed organic carbon (OC) aerosol mass at three remote marine sites in the Northern and Southern Hemispheres. In addition, we find the seasonal cycle of the isoprene SOA source is out of phase with the observed cycle in OC in the remote Southern Ocean. Based on these findings we suggest an insignificant role for isoprene in modulating remote marine aerosol abundances, giving further support to a recently postulated primary OC source in the remote marine atmosphere.

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Relationship between the Optical Properties and Chemical Composition of Urban Aerosol Particles in Lithuania

Advances in Meteorology ◽

10.1155/2018/8674173 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Julija Pauraite ◽

Kristina Plauškaitė ◽

Vadimas Dudoitis ◽

Vidmantas Ulevicius

Keyword(s):

Optical Properties ◽

Chemical Composition ◽

Organic Aerosol ◽

Single Scattering ◽

Chemical Compositions ◽

Spectra Analysis ◽

Average Value ◽

Aerosol Mass ◽

In Situ Investigation

In situ investigation results of aerosol optical properties (absorption and scattering) and chemical composition at an urban background site in Lithuania (Vilnius) are presented. Investigation was performed in May-June 2017 using an aerosol chemical speciation monitor (ACSM), a 7-wavelength Aethalometer and a 3-wavelength integrating Nephelometer. A positive matrix factorisation (PMF) was used for the organic aerosol mass spectra analysis to characterise the sources of ambient organic aerosol (OA). Five OA factors were identified: hydrocarbon-like OA (HOA), biomass-burning OA (BBOA), more and less oxygenated OA (LVOOA and SVOOA, respectively), and local hydrocarbon-like OA (LOA). The average absorption (at 470 nm) and scattering (at 450 nm) coefficients during the entire measurement campaign were 16.59 Mm−1 (standard deviation (SD) = 17.23 Mm−1) and 29.83 Mm−1 (SD = 20.45 Mm−1), respectively. Furthermore, the absorption and scattering Angström exponents (AAE and SAE, respectively) and single-scattering albedo (SSA) were calculated. The average AAE value at 470/660 nm was 0.97 (SD = 0.16) indicating traffic-related black carbon (BCtr) dominance. The average value of SAE (at 450/700 nm) was 1.93 (SD = 0.32) and could be determined by the submicron particle (PM1) dominance versus the supermicron ones (PM > 1 µm). The average value of SSA was 0.62 (SD = 0.13). Several aerosol types showed specific segregation in the SAE versus SSA plot, which underlines different optical properties due to various chemical compositions.

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Estimation of the Particulate Organic Carbon to Chlorophyll-a Ratio Using MODIS-Aqua in the East/Japan Sea, South Korea

Remote Sensing ◽

10.3390/rs12050840 ◽

2020 ◽

Vol 12 (5) ◽

pp. 840 ◽

Cited By ~ 1

Author(s):

Dabin Lee ◽

SeungHyun Son ◽

HuiTae Joo ◽

Kwanwoo Kim ◽

Myung Joon Kim ◽

...

Keyword(s):

Organic Carbon ◽

Particulate Organic Carbon ◽

Chlorophyll A ◽

Primary Productivity ◽

Seasonal Variability ◽

Japan Sea ◽

Global Ocean ◽

Phytoplankton Communities

In recent years, the change of marine environment due to climate change and declining primary productivity have been big concerns in the East/Japan Sea, Korea. However, the main causes for the recent changes are still not revealed clearly. The particulate organic carbon (POC) to chlorophyll-a (chl-a) ratio (POC:chl-a) could be a useful indicator for ecological and physiological conditions of phytoplankton communities and thus help us to understand the recent reduction of primary productivity in the East/Japan Sea. To derive the POC in the East/Japan Sea from a satellite dataset, the new regional POC algorithm was empirically derived with in-situ measured POC concentrations. A strong positive linear relationship (R2 = 0.6579) was observed between the estimated and in-situ measured POC concentrations. Our new POC algorithm proved a better performance in the East/Japan Sea compared to the previous one for the global ocean. Based on the new algorithm, long-term POC:chl-a ratios were obtained in the entire East/Japan Sea from 2003 to 2018. The POC:chl-a showed a strong seasonal variability in the East/Japan Sea. The spring and fall blooms of phytoplankton mainly driven by the growth of large diatoms seem to be a major factor for the seasonal variability in the POC:chl-a. Our new regional POC algorithm modified for the East/Japan Sea could potentially contribute to long-term monitoring for the climate-associated ecosystem changes in the East/Japan Sea. Although the new regional POC algorithm shows a good correspondence with in-situ observed POC concentrations, the algorithm should be further improved with continuous field surveys.

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A numerical evaluation of global oceanic emissions of α-pinene and isoprene

Atmospheric Chemistry and Physics ◽

10.5194/acp-10-2007-2010 ◽

2010 ◽

Vol 10 (4) ◽

pp. 2007-2015 ◽

Cited By ~ 69

Author(s):

G. Luo ◽

F. Yu

Keyword(s):

Numerical Evaluation ◽

Input Data ◽

Organic Aerosol ◽

Aerosol Formation ◽

Top Down ◽

Mixing Processes ◽

Bottom Up ◽

Phytoplankton Communities ◽

Oceanic Emissions

Abstract. A numerical evaluation of global oceanic emissions of α-pinene and isoprene based on both "bottom-up" and "top-down" methods is presented. We infer that the global "bottom-up" oceanic emissions of α-pinene and isoprene are 0.013 TgC yr−1 and 0.32 TgC yr−1, respectively. By constraining global chemistry model simulations with the shipborne measurement of Organics over the Ocean Modifying Particles in both Hemispheres summer cruise, we derived the global "top-down" oceanic α-pinene source of 29.5 TgC yr−1 and isoprene source of 11.6 TgC yr−1. Both the "bottom-up" and "top-down" values are subject to large uncertainties. The incomplete understanding of the in-situ phytoplankton communities and their range of emission potentials significantly impact the estimated global "bottom-up" oceanic emissions, while the estimated total amounts of the global "top-down" oceanic sources can be influenced by emission parameterizations, model and input data spatial resolutions, boundary layer mixing processes, and the treatments of chemical reactions. The global oceanic α-pinene source and its impact on organic aerosol formation is significant based on "top-down" method, but is negligible based on "bottom-up" approach. Our research highlights the importance of carrying out further research (especially measurements) to resolve the large offset in the derived oceanic organic emission based on two different approaches.

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Collection efficiency of α-pinene secondary organic aerosol particles explored via light scattering single particle aerosol mass spectrometry

10.5194/amt-2016-271 ◽

2016 ◽

Cited By ~ 2

Author(s):

Ellis Shipley Robinson ◽

Timothy B. Onasch ◽

Douglas Worsnop ◽

Neil M. Donahue

Keyword(s):

Light Scattering ◽

Single Particle ◽

Secondary Organic Aerosol ◽

Collection Efficiency ◽

Organic Aerosol ◽

Ionization Efficiency ◽

Aerosol Mass ◽

The Mean ◽

Hot Surface ◽

Effective Ionization

Abstract. We investigated the collection efficiency and effective ionization efficiency for secondary organic aerosol (SOA) particles made from α-pinene &plus; O3 using the single-particle capabilities of the Aerosol Mass Spectrometer (AMS). The mean count-based collection efficiency (CEp) for SOA across these experiments is 0.30 (±0.04 S.D.), ranging from 0.25 to 0.40. The mean mass-based collection efficiency (CEm) is 0.49 (±0.07 S.D.). This sub-unit collection efficiency and delayed vaporization is attributable to particle bounce in the vaporization region. Using the coupled optical and chemical detection of the light scattering single-particle (LSSP) module 5 of the AMS, we provide clear evidence that ''delayed vaporization'' is somewhat of a misnomer for these particles: SOA particles that appear within the chopper window do not vaporize at a slow rate; rather, they flash-vaporize, but often not on the initial impact with the vaporizer, and instead upon a subsequent impact with a hot surface in the vaporization region. We also find that the effective ionization efficiency (defined as ions per particle, IPP) decreases with delayed arrival time. CEp is not a function of particle size (for the mobility diameter range investigated, 170–460 nm), but we did see a decrease in CEp with thermodenuder temperature, implying that oxidation state and/or volatility can affect CEp for SOA.

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Characterization and source apportionment of submicron aerosol with aerosol mass spectrometer during the PRIDE-PRD 2006 campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-11-6911-2011 ◽

2011 ◽

Vol 11 (14) ◽

pp. 6911-6929 ◽

Cited By ~ 52

Author(s):

R. Xiao ◽

N. Takegawa ◽

M. Zheng ◽

Y. Kondo ◽

Y. Miyazaki ◽

...

Keyword(s):

Organic Carbon ◽

Urban Areas ◽

Organic Aerosol ◽

Water Soluble ◽

Aerosol Formation ◽

Aerosol Mass Spectrometer ◽

Air Masses ◽

Submicron Aerosol ◽

Pmf Model ◽

Aerosol Mass

Abstract. Size-resolved chemical compositions of non-refractory submicron aerosol were measured using an Aerodyne quadrupole aerosol mass spectrometer (Q-AMS) at the rural site Back Garden (BG), located ~50 km northwest of Guangzhou in July 2006. This paper characterized the submicron aerosol particles of regional air pollution in Pearl River Delta (PRD) in the southern China. Organics and sulfate dominated the submicron aerosol compositions, with average mass concentrations of 11.8 ± 8.4 μg m−3 and 13.5 ± 8.7 μg m−3, respectively. Unlike other air masses, the air masses originated from Southeast-South and passing through the PRD urban areas exhibited distinct bimodal size distribution characteristics for both organics and sulfate: the first mode peaked at vacuum aerodynamic diameters (Dva) ∼200 nm and the second mode occurred at Dva from 300–700 nm. With the information from AMS, it was found from this study that the first mode of organics in PRD regional air masses was contributed by both secondary organic aerosol formation and combustion-related emissions, which is different from most findings in other urban areas (first mode of organics primarily from combustion-related emissions). The analysis of AMS mass spectra data by positive matrix factorization (PMF) model identified three sources of submicron organic aerosol including hydrocarbon-like organic aerosol (HOA), low volatility oxygenated organic aerosol (LV-OOA) and semi-volatile oxygenated organic aerosol (SV-OOA). The strong correlation between HOA and EC indicated primary combustion emissions as the major source of HOA while a close correlation between SV-OOA and semi-volatile secondary species nitrate as well as between LV-OOA and nonvolatile secondary species sulfate suggested secondary aerosol formation as the major source of SV-OOA and LV-OOA at the BG site. However, LV-OOA was more aged than SV-OOA as its spectra was highly correlated with the reference spectra of fulvic acid, an indicator of aged and oxygenated aerosol. The origin of HOA and OOA (the sum of LV-OOA and SV-OOA) has been further confirmed by the statistics that primary organic carbon (POC) and secondary organic carbon (SOC), estimated by the EC tracer method, were closely correlated with HOA and OOA, respectively. The results of the EC tracer method and of the PMF model revealed that primary organic aerosol (POA) constituted ~34–47 % of OA mass and secondary organic aerosol (SOA) constituted ~53–66 % of regional organic aerosol in PRD during summer season. The presence of abundant SOA was consistent with water soluble organic carbon (WSOC) results (accounting for ~60 % of OC on average) by Miyazaki et al. (2009) for the same campaign. OOA correlated well with WSOC at the BG site, indicating that most OOA were water soluble. More specifically, approximately 86 % of LV-OOA and 61 % of SV-OOA were estimated as water soluble species on the basis of carbon content comparison.

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In situ measurement of PM1 organic aerosol in Beijing winter using a high-resolution aerosol mass spectrometer

Chinese Science Bulletin ◽

10.1007/s11434-011-4886-0 ◽

2011 ◽

Vol 57 (7) ◽

pp. 819-826 ◽

Cited By ~ 25

Author(s):

Quan Liu ◽

Yang Sun ◽

Bo Hu ◽

ZiRui Liu ◽

Shimono Akio ◽

...

Keyword(s):

High Resolution ◽

Mass Spectrometer ◽

Organic Aerosol ◽

In Situ Measurement ◽

Aerosol Mass Spectrometer ◽

Aerosol Mass

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Sources and Characteristics of Summertime Organic Aerosol in the Colorado Front Range: Perspective from Measurements and WRF-Chem Modeling

10.5194/acp-2018-57 ◽

2018 ◽

Author(s):

Roya Bahreini ◽

Ravan Ahmadov ◽

Stu A. McKeen ◽

Kennedy T. Vu ◽

Justin H. Dingle ◽

...

Keyword(s):

Boundary Layer ◽

Organic Aerosol ◽

Colorado Front Range ◽

Weather Research And Forecasting ◽

Front Range ◽

Top Down ◽

Mixing Ratios ◽

Oil And Natural Gas ◽

The Mean

Abstract. Evolution of organic aerosol (OA) and their precursors in the boundary layer of Colorado Front Range during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ, July–August 2014) was analyzed by in-situ measurements and chemical transport modeling. Measurements indicated significant production of secondary OA (SOA), with enhancement ratio of OA with respect to carbon monoxide (CO) reaching 0.068 ± 0.004 μg m−3 ppbv−1. At background mixing ratios of CO, up to ~ 2 μg m−3 background OA was observed, suggesting significant non-combustion contribution to OA in the Front Range. The mean concentration of OA in plumes with a high influence of oil and natural gas (O&G) emissions was ~ 40 % higher than in urban-influenced plumes. Positive matrix factorization confirmed a dominant contribution of secondary, oxygenated OA (OOA) in the boundary layer instead of fresh, hydrocarbon-like OA (HOA). Combinations of primary OA (POA) volatility assumptions, aging of semi-volatile species, and different emission estimates from the O&G sector were used in the Weather Research and Forecasting model, coupled with Chemistry (WRF-Chem) simulation scenarios. The assumption of semi-volatile POA resulted in greater than a factor of 10 lower POA concentrations compared to PMF-resolved HOA. Including a top-down modified O&G emissions resulted in substantially better agreements in modeled ethane, toluene, hydroxyl radical, and ozone compared to measurements in the high O&G-influenced plumes. By including emissions from the O&G sector using the top-down approach, it was estimated that the O&G sector contributed to

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Tara Pacific Expedition’s Atmospheric Measurements of Marine Aerosols across the Atlantic and Pacific Oceans: Overview and Preliminary Results

Bulletin of the American Meteorological Society ◽

10.1175/bams-d-18-0224.1 ◽

2020 ◽

Vol 101 (5) ◽

pp. E536-E554 ◽

Cited By ~ 2

Author(s):

J. M. Flores ◽

G. Bourdin ◽

O. Altaratz ◽

M. Trainic ◽

N. Lang-Yona ◽

...

Keyword(s):

Environmental Conditions ◽

Chemical Properties ◽

Number Concentration ◽

Marine Atmosphere ◽

Marine Aerosol ◽

Marine Aerosols ◽

Atmospheric Measurements ◽

Preliminary Results ◽

Production Mechanisms

Abstract Marine aerosols play a significant role in the global radiative budget, in clouds’ processes, and in the chemistry of the marine atmosphere. There is a critical need to better understand their production mechanisms, composition, chemical properties, and the contribution of ocean-derived biogenic matter to their mass and number concentration. Here we present an overview of a new dataset of in situ measurements of marine aerosols conducted over the 2.5-yr Tara Pacific Expedition over 110,000 km across the Atlantic and Pacific Oceans. Preliminary results are presented here to describe the new dataset that will be built using this novel set of measurements. It will characterize marine aerosols properties in detail and will open a new window to study the marine aerosol link to the water properties and environmental conditions.

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Hygroscopic properties of smoke-generated organic aerosol particles emitted in the marine atmosphere

Atmospheric Chemistry and Physics ◽

10.5194/acp-13-9819-2013 ◽

2013 ◽

Vol 13 (19) ◽

pp. 9819-9835 ◽

Cited By ~ 27

Author(s):

A. Wonaschütz ◽

M. Coggon ◽

A. Sorooshian ◽

R. Modini ◽

A. A. Frossard ◽

...

Keyword(s):

Mass Fraction ◽

Cloud Condensation Nuclei ◽

Organic Aerosol ◽

Water Soluble ◽

Marine Atmosphere ◽

Hygroscopic Growth ◽

Organic Mass ◽

Aerosol Mass ◽

Hygroscopic Properties ◽

Mass Fractions

Abstract. During the Eastern Pacific Emitted Aerosol Cloud Experiment (E-PEACE), a plume of organic aerosol was produced by a smoke generator and emitted into the marine atmosphere from aboard the R/V Point Sur. In this study, the hygroscopic properties and the chemical composition of the plume were studied at plume ages between 0 and 4 h in different meteorological conditions. In sunny conditions, the plume particles had very low hygroscopic growth factors (GFs): between 1.05 and 1.09 for 30 nm and between 1.02 and 1.1 for 150 nm dry size at a relative humidity (RH) of 92%, contrasted by an average marine background GF of 1.6. New particles were produced in large quantities (several 10 000 cm−3), which lead to substantially increased cloud condensation nuclei (CCN) concentrations at supersaturations between 0.07 and 0.88%. Ratios of oxygen to carbon (O : C) and water-soluble organic mass (WSOM) increased with plume age: from < 0.001 to 0.2, and from 2.42 to 4.96 μg m−3, respectively, while organic mass fractions decreased slightly (~ 0.97 to ~ 0.94). High-resolution aerosol mass spectrometer (AMS) spectra show that the organic fragment m/z 43 was dominated by C2H3O+ in the small, new particle mode and by C3H7+ in the large particle mode. In the marine background aerosol, GFs for 150 nm particles at 40% RH were found to be enhanced at higher organic mass fractions: an average GF of 1.06 was observed for aerosols with an organic mass fraction of 0.53, and a GF of 1.04 for an organic mass fraction of 0.35.

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