Aerosol optical extinction during the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) 2014 summertime field campaign, Colorado, USA
Item
Title (Dublin Core)
Aerosol optical extinction during the Front Range Air Pollution and
Photochemistry Éxperiment (FRAPPÉ) 2014 summertime field campaign,
Colorado, USA
Photochemistry Éxperiment (FRAPPÉ) 2014 summertime field campaign,
Colorado, USA
Description (Dublin Core)
Summertime aerosol optical extinction (<i>β</i><sub>ext</sub>) was measured in the Colorado Front Range and Denver metropolitan area as part of the Front Range Air Pollution and Photochemistry Éxperiment (FRAPPÉ) campaign during July–August 2014. An Aerodyne cavity attenuated phase shift particle light extinction monitor (CAPS-PM<sub>ex</sub>) was deployed to measure <i>β</i><sub>ext</sub> (at average relative humidity of 20 ± 7 %) of submicron aerosols at <i>λ</i> = 632 nm at 1 Hz. Data from a suite of gas-phase instrumentation were used to interpret <i>β</i><sub>ext</sub> behavior in various categories of air masses and sources. Extinction enhancement ratios relative to CO (Δ<i>β</i><sub>ext</sub> ∕ ΔCO) were higher in aged urban air masses compared to fresh air masses by ∼ 50 %. The resulting increase in Δ<i>β</i><sub>ext</sub> ∕ ΔCO for highly aged air masses was accompanied by formation of secondary organic aerosols (SOAs). In addition, the impacts of aerosol composition on <i>β</i><sub>ext</sub> in air masses under the influence of urban, natural oil and gas operations (O&G), and agriculture and livestock operations were evaluated. Estimated non-refractory mass extinction efficiency (MEE) values for different air mass types ranged from 1.51 to 2.27 m<sup>2</sup> g<sup>−1</sup>, with the minimum and maximum values observed in urban and agriculture-influenced air masses, respectively. The mass distribution for organic, nitrate, and sulfate aerosols presented distinct profiles in different air mass types. During 11–12 August, regional influence of a biomass burning event was observed, increasing the background <i>β</i><sub>ext</sub> and estimated MEE values in the Front Range.
Creator (Dublin Core)
Dingle, Justin H.
Vu, Kennedy
Bahreini, Roya
Apel, Eric C.
Campos, Teresa L.
Flocke, Frank
Fried, Alan
Herndon, Scott
Hills, Alan J.
Hornbrook, Rebecca S.
Huey, Greg
Kaser, Lisa
Montzka, Denise D.
Nowak, John B.
Reeves, Mike
Richter, Dirk
Roscioli, Joseph R.
Shertz, Stephen
Stell, Meghan
Tanner, David
Tyndall, Geoff
Walega, James
Weibring, Petter
Weinheimer, Andrew
Date (Dublin Core)
2018-09-10
Type (Dublin Core)
Text
Format (Dublin Core)
application/pdf
Identifier (Dublin Core)
10.5194/acp-16-11207-2016
https://acp.copernicus.org/articles/16/11207/2016/
Source (Dublin Core)
eISSN: 1680-7324
Language (Dublin Core)
eng
