Contributions of dust and biomass burning to aerosols at a Colorado mountain-top site

Hallar, AG; Petersen, R; Andrews, E; Michalsky, J; McCubbin, IB; Ogren, JA

HERO ID

3259135

Reference Type

Journal Article

Year

2015

Language

English

HERO ID 3259135
In Press No
Year 2015
Title Contributions of dust and biomass burning to aerosols at a Colorado mountain-top site
Authors Hallar, AG; Petersen, R; Andrews, E; Michalsky, J; McCubbin, IB; Ogren, JA
Journal Atmospheric Chemistry and Physics
Volume 15
Issue 23
Page Numbers 13665-13679
Abstract Visible Multifilter Rotating Shadowband Radiometer (vis-MFRSR) data were collected at Storm Peak Laboratory (SPL), a mountain-top facility in northwest Colorado, from 1999 to 2011 and in 2013. From 2011 to 2014, in situ measurements of aerosol light scattering were also obtained. Using these data sets together, the seasonal impact of dust and biomass burning is considered for the western USA. Analysis indicates that the median contributions to spring and summer aerosol optical depth (AOD) from dust and biomass-burning aerosols across the data set are comparable. The mean AOD is slightly greater in the summer, with significantly more frequent and short-duration high AOD measurements due to biomass-burning episodes than in the spring. The angstrom ngstrom exponent showed a significant increase in the summer for both the in situ and vis-MFRSR data, suggesting an increase in combustion aerosols. Spring dust events are less distinguishable in the in situ data than the column measurement, suggesting that a significant amount of dust may be found above the elevation of SPL, 3220 ma.s.l. Twenty-two known case studies of intercontinental dust, regional dust, and biomass-burning events were investigated. These events were found to follow a similar pattern, in both aerosol loading and angstrom ngstrom exponent, as the seasonal mean signal in both the vis-MFRSR and ground-based nephelometer. This data set highlights the wide-scale implications of a warmer, drier climate on visibility in the western USA.
Doi 10.5194/acp-15-13665-2015
Wosid WOS:000367189600024
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English