Conference proceeding
Determination of seasonal, diurnal, and height resolved average number concentration in a pollution impacted rural continental location
AIP Conference Proceedings, Vol.1527(1), pp.583-586
05/24/2013
DOI: 10.1063/1.4803338
Abstract
The impact of aerosols on Earth's radiation balance and the associated climate forcing effects of aerosols represent significant uncertainties in assessment reports. The main source of ultrafine aerosols in the atmosphere is the nucleation and subsequent growth of gas phase aerosol precursors into liquid or solid phase particles. Long term records of aerosol number, nucleation event frequency, and vertical profiles of number concentration are rare. The data record from multiagency monitoring assets at Bondville, IL can contribute important information on long term and vertically resolved patterns. Although particle number size distribution data are only occasionally available at Bondville, highly time-resolved particle number concentration data have been measured for nearly twenty years by the NOAA ESRL Global Monitoring Division. Furthermore, vertically-resolved aerosol counts and other aerosol physical parameters are available from more than 300 flights of the NOAA Airborne Aerosol Observatory (AAO). These data sources are used to better understand the seasonal, diurnal, and vertical variation and trends in atmospheric aerosols. The highest peaks in condensation nuclei greater than 14 nm occur during the spring months (May, April) with slightly lower peaks during the fall months (September, October). The diurnal pattern of aerosol number has a midday peak and the timing of the peak has seasonal patterns (earlier during warm months and later during colder months). The seasonal and diurnal patterns of high particle number peaks correspond to seasons and times of day associated with low aerosol mass and surface area. Average vertical profiles show a nearly monotonic decrease with altitude in all months, and with peak magnitudes occurring in the spring and fall. Individual flight tracks show evidence of plumes (i.e., enhanced aerosol number is limited to a small altitude range, is not homogeneous horizontally, or both) as well as periods with enhanced particle number throughout the mixed layer. As primary sources of aerosols are unable to explain most of these phenomena, the observed features in ultrafine aerosols are strongly connected to secondary formation and growth.
Details
- Title: Subtitle
- Determination of seasonal, diurnal, and height resolved average number concentration in a pollution impacted rural continental location
- Creators
- Robert L BullardCharles O StanierJohn A OgrenPatrick J Sheridan
- Resource Type
- Conference proceeding
- Publication Details
- AIP Conference Proceedings, Vol.1527(1), pp.583-586
- DOI
- 10.1063/1.4803338
- ISSN
- 0094-243X
- eISSN
- 1551-7616
- Language
- English
- Date published
- 05/24/2013
- Academic Unit
- Chemical and Biochemical Engineering
- Record Identifier
- 9984197431902771
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