In:
Atmospheric Chemistry and Physics, Copernicus GmbH, Vol. 18, No. 4 ( 2018-03-01), p. 2949-2971
Abstract:
Abstract. The climatological variation of aerosol properties and the planetary
boundary layer (PBL) during 2013–2015 over the
Yangtze River Delta (YRD) region were investigated by employing ground-based Micro Pulse Lidar (MPL) and CE-318
sun-photometer observations. Combining Moderate Resolution Imaging Spectroradiometer (MODIS) and Cloud-Aerosol Lidar and Infrared
Pathfinder Satellite Observation (CALIPSO) satellite products, enhanced haze pollution events affected by
different types of aerosol over the YRD region were analyzed through vertical structures, spatial distributions, backward
trajectories, and the potential source contribution function (PSCF) model. The results show that aerosols in the YRD are
dominated by fine-mode particles, except in March. The aerosol optical depth (AOD) in June and September is higher due to
high single scattering albedo (SSA) from hygroscopic growth, but it is lower in July and August due to wet deposition from
precipitation. The PBL height (PBLH) is greater (means ranging from 1.23 to 1.84 km) and more variable in the
warmer months of March to August, due to the stronger diurnal cycle and exchange of heat. Northern fine-mode pollutants
are brought to the YRD at a height of 1.5 km. The SSA increases, blocking the radiation to the surface, and cooling
the surface, thereby weakening turbulence, lowering the PBL, and in turn accelerating the accumulation of pollutants,
creating a feedback to the cooling effect. Originated from the deserts in Xinjiang and Inner Mongolia, long-range
transported dust masses are seen at heights of about 2 km over the YRD region with an
SSA440 nm below 0.84, which heat air and raise the PBL, accelerating the diffusion of dust
particles. Regional transport from biomass-burning spots to the south of the YRD region bring mixed aerosol particles at
a height below 1.5 km, resulting in an SSA440 nm below 0.89. During the winter, the
accumulation of the local emission layer is facilitated by stable weather conditions, staying within the PBL even below
0.5 km.
Type of Medium:
Online Resource
ISSN:
1680-7324
DOI:
10.5194/acp-18-2949-2018
DOI:
10.5194/acp-18-2949-2018-supplement
Language:
English
Publisher:
Copernicus GmbH
Publication Date:
2018
detail.hit.zdb_id:
2092549-9
detail.hit.zdb_id:
2069847-1
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