Diurnal Variation of Co-located Surface PM Concentration and Column AOD
Abstract
We examined the correlation between the diurnal cycle of co-located surface particulate matter (PM), or aerosol, concentration and column aerosol optical depth (AOD) using continuous (hourly data for multiple years) from two ground-based observation networks. On average the daily variation of PM (Max-Min)/Mean is ~120-150%, i.e. the daily variation is comparable or larger than its mean magnitude, and for column AOD, its daily variation is ~80% of its mean. At the four urban sites we examined, surface PM is correlated with AOD pretty well (R^2>0.6) on daily bases. On finer time scale, the surface PM is affected by local emission pattern and local-to-regional circulation changes, while for column AOT, more factors need to be considered, esp. the aerosol vertical profile and changing of particle size during the day. Observed PBL and other meteorological conditions are combined to help link the surface and column aerosol observation and estimate their contribution to aerosol's diurnal variations, which is found to be variable during different seasons.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2011
- Bibcode:
- 2011AGUFM.A13E0397T
- Keywords:
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- 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE;
- 0305 ATMOSPHERIC COMPOSITION AND STRUCTURE / Aerosols and particles;
- 0325 ATMOSPHERIC COMPOSITION AND STRUCTURE / Evolution of the atmosphere;
- 0345 ATMOSPHERIC COMPOSITION AND STRUCTURE / Pollution: urban and regional