scholarly journals Glyoxal's impact on dry ammonium salts: fast and reversible surface aerosol browning

2020 ◽  
Vol 20 (16) ◽  
pp. 9581-9590
Author(s):  
David O. De Haan ◽  
Lelia N. Hawkins ◽  
Kevin Jansen ◽  
Hannah G. Welsh ◽  
Raunak Pednekar ◽  
...  
Keyword(s):  
Gas Phase ◽  
Radiative Forcing ◽  
Aerosol Particles ◽  
Empirical Relationship ◽  
Optical Measurements ◽  
Carbon Formation ◽  
Cloud Droplets ◽  
Brown Carbon ◽  
Ultraviolet Range ◽  
Dry Conditions

Abstract. Alpha-dicarbonyl compounds are believed to form brown carbon in the atmosphere via reactions with ammonium sulfate (AS) in cloud droplets and aqueous aerosol particles. In this work, brown carbon formation in AS and other aerosol particles was quantified as a function of relative humidity (RH) during exposure to gas-phase glyoxal (GX) in chamber experiments. Under dry conditions (RH < 5 %), solid AS, AS–glycine, and methylammonium sulfate (MeAS) aerosol particles brown within minutes upon exposure to GX, while sodium sulfate particles do not. When GX concentrations decline, browning goes away, demonstrating that this dry browning process is reversible. Declines in aerosol albedo are found to be a function of [GX]2 and are consistent between AS and AS–glycine aerosol. Dry methylammonium sulfate aerosol browns 4 times more than dry AS aerosol, but deliquesced AS aerosol browns much less than dry AS aerosol. Optical measurements at 405, 450, and 530 nm provide an estimated Ångstrom absorbance coefficient of -16±4. This coefficient and the empirical relationship between GX and albedo are used to estimate an upper limit to global radiative forcing by brown carbon formed by 70 ppt GX reacting with AS (+7.6×10-5 W m−2). This quantity is < 1 % of the total radiative forcing by secondary brown carbon but occurs almost entirely in the ultraviolet range.

scholarly journals Glyoxal's impact on dry ammonium salts: fast and reversible surface aerosol browning

2020 ◽  
Author(s):  
David O. De Haan ◽  
Lelia N. Hawkins ◽  
Kevin Jansen ◽  
Hannah G. Welsh ◽  
Raunak Pednekar ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Gas Phase ◽  
Ammonium Sulfate ◽  
Aerosol Particles ◽  
Ammonium Salts ◽  
Carbon Formation ◽  
Cloud Droplets ◽  
Brown Carbon ◽  
Dicarbonyl Compounds ◽  
Dry Conditions

Abstract. Alpha-dicarbonyl compounds are believed to form brown carbon in the atmosphere via reactions with ammonium sulfate (AS) in cloud droplets and aqueous aerosol particles. In this work, brown carbon formation in AS and other aerosol particles was quantified as a function of relative humidity (RH) during exposure to gas-phase glyoxal (GX) in chamber experiments. Under dry conditions (RH 

scholarly journals Reducing uncertainties associated with filter-based optical measurements of soot aerosol particles with chemical information

2010 ◽  
Vol 3 (2) ◽  
pp. 1197-1227 ◽  
Author(s):  
J. E. Engström ◽  
C. Leck
Keyword(s):  
Light Scattering ◽  
Indian Ocean ◽  
Radiative Forcing ◽  
Light Transmission ◽  
Aerosol Particles ◽  
Winter Season ◽  
Optical Measurements ◽  
Chemical Information ◽  
Polycarbonate Membrane ◽  
South Indian

Abstract. Of the many identified and potential effects of atmospheric aerosol particles on climate, those of soot particles are the most uncertain, in that analytical techniques concerning soot are far from satisfactory. One concern when applying filter-based optical measurements of soot is that they suffer from systematic errors due to the light scattering of non-absorbing particles co-deposited on the filter, such as inorganic salts and mineral dust. In addition to an optical correction of the non-absorbing material this study provides a protocol for correction of light scattering based on the chemical quantification of the material, which is a novelty. A newly designed Particle Soot Absorption Photometer was constructed to measure light transmission on particle accumulating filters, which includes an additional sensor recording backscattered light. The choice of polycarbonate membrane filters avoided high chemical blank values and reduced errors associated with length of the light path through the filter. Two protocols for corrections were applied to aerosol samples collected at the Maldives Climate Observatory Hanimaadhoo during episodes with either continentally influenced air from the Indian/Arabian subcontinents (winter season) or pristine air from the Southern Indian Ocean (summer monsoon). The two ways of correction (optical and chemical) lowered the particle light absorption of soot by 63 to 61%, respectively, for data from the Arabian Sea sourced group, resulting in median soot absorption coefficients of 4.2 and 3.5 Mm-1. Corresponding values for the South Indian Ocean data were 69 and 97% (0.38 and 0.02 Mm-1). A comparison with other studies in the area indicated an overestimation of their soot levels, by up to two orders of magnitude. This raises the necessity for chemical correction protocols on optical filter-based determinations of soot, before even the sign on the radiative forcing based on their effects can be assessed.

scholarly journals CHASER: An Innovative Satellite Mission Concept to Measure the Effects of Aerosols on Clouds and Climate

2013 ◽  
Vol 94 (5) ◽  
pp. 685-694 ◽  
Author(s):  
Nilton O. Rennó ◽  
Earle Williams ◽  
Daniel Rosenfeld ◽  
David G. Fischer ◽  
Jürgen Fischer ◽  
...  
Keyword(s):  
Radiative Forcing ◽  
Cloud Condensation Nuclei ◽  
Aerosol Particles ◽  
Satellite Mission ◽  
Cloud Droplets ◽  
Cloud Particle ◽  
Intergovernmental Panel ◽  
Fundamental Process ◽  
A New Technique

The formation of cloud droplets on aerosol particles, technically known as the activation of cloud condensation nuclei (CCN), is the fundamental process driving the interactions of aerosols with clouds and precipitation. The Intergovernmental Panel on Climate Change (IPCC) and the Decadal Survey indicate that the uncertainty in how clouds adjust to aerosol perturbations dominates the uncertainty in the overall quantification of the radiative forcing attributable to human activities. Measurements by current satellites allow the determination of crude profiles of cloud particle size, but not of the activated CCN that seed them. The Clouds, Hazards, and Aerosols Survey for Earth Researchers (CHASER) mission concept responds to the IPCC and Decadal Survey concerns, utilizing a new technique and high-heritage instruments to measure all the quantities necessary to produce the first global survey maps of activated CCN and the properties of the clouds associated with them. CHASER also determines the activated CCN concentration and cloud thermodynamic forcing simultaneously, allowing the effects of each to be distinguished.

scholarly journals Compilation of Henry's law constants, version 3.99

2014 ◽  
Vol 14 (21) ◽  
pp. 29615-30521 ◽  
Author(s):  
R. Sander
Keyword(s):  
Gas Phase ◽  
Environmental Chemistry ◽  
Aerosol Particles ◽  
Dilute Solution ◽  
Henry's Law ◽  
Cloud Droplets ◽  
Henry’S Law ◽  
Equilibrium Ratio ◽  
Henry’S Law Constants ◽  
Henry's Law Constants

Abstract. Many atmospheric chemicals occur in the gas phase as well as in liquid cloud droplets and aerosol particles. Therefore, it is necessary to understand the distribution between the phases. According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution. Henry's law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format. The compilation contains 14775 values of Henry's law constants for 3214 species, collected from 639 references. It is also available on the internet at http://www.henrys-law.org.

scholarly journals Radical-Initiated Brown Carbon Formation in Sunlit Carbonyl–Amine–Ammonium Sulfate Mixtures and Aqueous Aerosol Particles

2022 ◽  
Author(s):  
Natalie G. Jimenez ◽  
Kyle D. Sharp ◽  
Tobin Gramyk ◽  
Duncan Z. Ugland ◽  
Matthew-Khoa Tran ◽  
...  
Keyword(s):  
Ammonium Sulfate ◽  
Aerosol Particles ◽  
Carbon Formation ◽  
Brown Carbon

scholarly journals Aging of atmospheric aerosols and the role of iron in catalyzing brown carbon formation

2021 ◽  
Author(s):  
Hind A. A. Al-Abadleh
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Atmospheric Aerosols ◽  
Secondary Organic Aerosol ◽  
Organic Aerosol ◽  
Atmospheric Oxidation ◽  
Carbon Formation ◽  
Brown Carbon ◽  
Volatile Organic

Extensive research has been done on the processes that lead to the formation of secondary organic aerosol (SOA) including atmospheric oxidation of volatile organic compounds (VOCs) from biogenic and anthropogenic...

scholarly journals Mineral and biological ice-nucleating particles above the South East of the British Isles

2021 ◽  
Author(s):  
Alberto Sanchez-Marroquin ◽  
Jonathan S. West ◽  
Ian Burke ◽  
James B McQuaid ◽  
Benjamin John Murray
Keyword(s):  
Aerosol Particles ◽  
Ice Formation ◽  
British Isles ◽  
The South ◽  
Cloud Droplets ◽  
Homogeneous Freezing

A small fraction of aerosol particles known as Ice-Nucleating Particles (INPs) have the potential to trigger ice formation in cloud droplets at higher temperatures than homogeneous freezing. INPs can strongly...

First Quantification of Imidazoles in Ambient Aerosol Particles: Potential Photosensitizers, Brown Carbon Constituents, and Hazardous Components

2016 ◽  
Vol 50 (3) ◽  
pp. 1166-1173 ◽  
Author(s):  
Monique Teich ◽  
Dominik van Pinxteren ◽  
Simonas Kecorius ◽  
Zhibin Wang ◽  
Hartmut Herrmann
Keyword(s):  
Aerosol Particles ◽  
Brown Carbon ◽  
Ambient Aerosol

scholarly journals Investigation of water adsorption and hygroscopicity of atmospherically relevant particles using a commercial vapor sorption analyzer

2017 ◽  
Vol 10 (10) ◽  
pp. 3821-3832 ◽  
Author(s):  
Wenjun Gu ◽  
Yongjie Li ◽  
Jianxi Zhu ◽  
Xiaohong Jia ◽  
Qinhao Lin ◽  
...  
Keyword(s):  
Atmospheric Chemistry ◽  
Radiative Forcing ◽  
Water Adsorption ◽  
Theoretical Data ◽  
Atmospheric Particles ◽  
Relative Mass ◽  
Nonspherical Particles ◽  
Vapor Sorption ◽  
Hygroscopic Growth ◽  
Dry Conditions

Abstract. Water adsorption and hygroscopicity are among the most important physicochemical properties of aerosol particles, largely determining their impacts on atmospheric chemistry, radiative forcing, and climate. Measurements of water adsorption and hygroscopicity of nonspherical particles under subsaturated conditions are nontrivial because many widely used techniques require the assumption of particle sphericity. In this work we describe a method to directly quantify water adsorption and mass hygroscopic growth of atmospheric particles for temperature in the range of 5–30 °C, using a commercial vapor sorption analyzer. A detailed description of instrumental configuration and experimental procedures, including relative humidity (RH) calibration, is provided first. It is then demonstrated that for (NH4)2SO4 and NaCl, deliquescence relative humidities and mass hygroscopic growth factors measured using this method show good agreements with experimental and/or theoretical data from literature. To illustrate its ability to measure water uptake by particles with low hygroscopicity, we used this instrument to investigate water adsorption by CaSO4 ⋅ 2H2O as a function of RH at 25 °C. The mass hygroscopic growth factor of CaSO4 ⋅ 2H2O at 95 % RH, relative to that under dry conditions (RH  < 1 %), was determined to be (0.450±0.004) % (1σ). In addition, it is shown that this instrument can reliably measure a relative mass change of 0.025 %. Overall, we have demonstrated that this commercial instrument provides a simple, sensitive, and robust method to investigate water adsorption and hygroscopicity of atmospheric particles.

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