Characterization of aerosol types over Lake Urmia Basin

Atmospheric aerosols affect the Earth's climate, air quality, and thus human health. This study used the Aerosol Optical Depth (AOD) and the Ångström exponent to cluster different particle types over the Lake Urmia Basin. This classification found desert dust and marine (mixed with continental or local-pollution aerosols) as two main aerosol types over the region, while their sources are not well defined. Although different air masses and wind circulation over the study domain in varied months can help to distinguish aerosol sources, measurements are crucial for a complete evaluation.

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Identification of the Aerosol Types over Athens, Greece: The Influence of Air-Mass Transport

Advances in Meteorology ◽

10.1155/2010/168346 ◽

2010 ◽

Vol 2010 ◽

pp. 1-15 ◽

Cited By ~ 8

Author(s):

D. G. Kaskaoutis ◽

P. G. Kosmopoulos ◽

H. D. Kambezidis ◽

P. T. Nastos

Keyword(s):

Winter Season ◽

Saharan Dust ◽

Dust Particles ◽

Hysplit Model ◽

Air Mass ◽

Back Trajectories ◽

Air Masses ◽

Local Pollution ◽

Coarse Mode ◽

Aerosol Types

Aerosol optical depth at 550 nm () and fine-mode (FM) fraction data from Terra-MODIS were obtained over the Greater Athens Area covering the period February 2000–December 2005. Based on both and FM values three main aerosol types have been discriminated corresponding to urban/industrial aerosols, clean maritime conditions, and coarse-mode, probably desert dust, particles. Five main sectors were identified for the classification of the air-mass trajectories, which were further used in the analysis of the ( and FM data for the three aerosol types). The HYSPLIT model was used to compute back trajectories at three altitudes to investigate the relation between -FM and wind sector depending on the altitude. The accumulation of local pollution is favored in spring and corresponds to air masses at lower altitudes originating from Eastern Europe and the Balkan. Clean maritime conditions are rare over Athens, limited in the winter season and associated with air masses from the Western or Northwestern sector. The coarse-mode particles origin seems to be more complicated proportionally to the season. Thus, in summer the Northern sector dominates, while in the other seasons, and especially in spring, the air masses belong to the Southern sector enriched with Saharan dust aerosols.

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Characterization of NOx-Ox relationships during daytime interchange of air masses over a mountain pass in the Mexico City megalopolis

Atmospheric Environment ◽

10.1016/j.atmosenv.2017.11.017 ◽

2018 ◽

Vol 177 ◽

pp. 100-110 ◽

Cited By ~ 6

Author(s):

J.S. García-Yee ◽

R. Torres-Jardón ◽

H. Barrera-Huertas ◽

T. Castro ◽

O. Peralta ◽

...

Keyword(s):

Mexico City ◽

Mountain Pass ◽

Air Masses

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Review on the manuscript "Molecular Characterization of Alkyl Nitrates in Atmospheric Aerosols by Ion Mobility Mass Spectrometry” by Xuan Zhang et al.

10.5194/amt-2019-184-rc1 ◽

2019 ◽

Author(s):

Anonymous

Keyword(s):

Mass Spectrometry ◽

Molecular Characterization ◽

Ion Mobility ◽

Atmospheric Aerosols ◽

Ion Mobility Mass Spectrometry ◽

Alkyl Nitrates

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Characterization of carboxylic acids in atmospheric aerosols using hydrophilic interaction liquid chromatography tandem mass spectrometry

Journal of Chromatography A ◽

10.1016/j.chroma.2011.05.020 ◽

2011 ◽

Vol 1218 (28) ◽

pp. 4417-4425 ◽

Cited By ~ 35

Author(s):

Zoran Kitanovski ◽

Irena Grgić ◽

Marjan Veber

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Tandem Mass Spectrometry ◽

Carboxylic Acids ◽

Atmospheric Aerosols ◽

Tandem Mass ◽

Hydrophilic Interaction ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass

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Why Hasn’t Earth Warmed as Much as Expected?

Journal of Climate ◽

10.1175/2009jcli3461.1 ◽

2010 ◽

Vol 23 (10) ◽

pp. 2453-2464 ◽

Cited By ~ 65

Author(s):

Stephen E. Schwartz ◽

Robert J. Charlson ◽

Ralph A. Kahn ◽

John A. Ogren ◽

Henning Rodhe

Keyword(s):

Climate Sensitivity ◽

Atmospheric Aerosols ◽

Climate Models ◽

Substantial Reduction ◽

Heat Content ◽

Historical Record ◽

Intergovernmental Panel ◽

Aerosol Forcing ◽

Best Estimate ◽

Earth’S Climate

Abstract The observed increase in global mean surface temperature (GMST) over the industrial era is less than 40% of that expected from observed increases in long-lived greenhouse gases together with the best-estimate equilibrium climate sensitivity given by the 2007 Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). Possible reasons for this warming discrepancy are systematically examined here. The warming discrepancy is found to be due mainly to some combination of two factors: the IPCC best estimate of climate sensitivity being too high and/or the greenhouse gas forcing being partially offset by forcing by increased concentrations of atmospheric aerosols; the increase in global heat content due to thermal disequilibrium accounts for less than 25% of the discrepancy, and cooling by natural temperature variation can account for only about 15%. Current uncertainty in climate sensitivity is shown to preclude determining the amount of future fossil fuel CO2 emissions that would be compatible with any chosen maximum allowable increase in GMST; even the sign of such allowable future emissions is unconstrained. Resolving this situation, by empirical determination of the earth’s climate sensitivity from the historical record over the industrial period or through use of climate models whose accuracy is evaluated by their performance over this period, is shown to require substantial reduction in the uncertainty of aerosol forcing over this period.

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Influence of dust and sea-salt sandwich effect on precipitation chemistry over the Western Ghats during summer monsoon

Scientific Reports ◽

10.1038/s41598-019-55245-0 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

L. Yang ◽

S. Mukherjee ◽

G. Pandithurai ◽

V. Waghmare ◽

P. D. Safai

Keyword(s):

Summer Monsoon ◽

High Surface ◽

Precipitation Chemistry ◽

Sea Salt ◽

Monsoon Period ◽

Air Masses ◽

Range Transport ◽

Wind Regimes ◽

High Uncertainty

AbstractAssessment of Sea Salt (SS) and Non-Sea Salt (NSS) aerosols in rainwater is important to understand the characterization of marine and continental aerosols and their source pathways. Sea salt quantification based on standard seawater ratios are primarily constrained with high uncertainty with its own limitations. Here, by the novelty of k-mean clustering and Positive Matrix Factorization (PMF) analysis, we segregate the air masses into two distinct clusters (oceanic and continental) during summer monsoon period signifying the complex intermingle of sources that act concomitantly. The rainwater composition during strong south-westerly wind regimes (cluster 2-oceanic) was profoundly linked with high sea salt and dust, whereas north-westerly low wind regimes (cluster 1-continental) showed an increase in SO42− and NO3−. However, SO42− abundance over NO3− in rain-water depicted its importance as a major acidifying ion at the region. The satellite-based observations indicate the presence of mid-tropospheric dust at the top (3–5 km) and marine sea salt at bottom acts as a “sandwich effect” for maritime clouds that leads to elevated Ca2+, Na+, Mg2+, and Cl− in rainwater. This characteristic feature is unique as sea spray generation due to high surface winds and dust aloft is only seen during this period. Furthermore, four source factors (secondary inorganic aerosol, mixed dust & sea salt, biomass burning & fertilizer use, and calcium neutralization) derived from PMF analysis showed contribution from local activities as well as long-range transport as dominant sources for the rainwater species.

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