Enhanced heating rate of black carbon above the planetary boundary layer over megacities in summertime

The fast development of a secondary aerosol layer was observed over megacities in eastern Asia during summertime. Within three hours, from midday to early afternoon, the contribution of secondary aerosols above the planetary boundary layer (PBL) increased by a factor of three to five, and the coatin...

Full description

Saved in:
Bibliographic Details
Published in:Environmental research letters 2019-12, Vol.14 (12), p.124003
Main Authors: Liu, Dantong, Zhao, Delong, Xie, Zhenzhen, Yu, Chenjie, Chen, Ying, Tian, Ping, Ding, Shuo, Hu, Kang, Lowe, Douglas, Liu, Quan, Zhou, Wei, Wang, Fei, Sheng, Jiujiang, Kong, Shaofei, Hu, Dawei, Wang, Zhenzhu, Huang, Mengyu, Ding, Deping
Format: Article
Language:English
Subjects:
Absorption
absorption enhancement
Aerosols
Black carbon
Boundary layers
Carbon
cloud reflection
Heating rate
High temperature effects
Megacities
Photochemical reactions
Photochemicals
Planetary boundary layer
Radiation
Solar radiation
Summer
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The fast development of a secondary aerosol layer was observed over megacities in eastern Asia during summertime. Within three hours, from midday to early afternoon, the contribution of secondary aerosols above the planetary boundary layer (PBL) increased by a factor of three to five, and the coatings on black carbon (BC) also increased and enhanced its absorption efficiency by 50%. This tended to result from the intensive actinic flux received above the PBL which promoted photochemical reactions. The absorption of BC could be further amplified by the strong reflection of solar radiation over the cloud top across the PBL. This enhanced heating effect of BC introduced by combined processes (intensive solar radiation, secondary formation and cloud reflection) may considerably increase the temperature inversion above the PBL. This mechanism should be considered when evaluating the radiative impact of BC, especially for polluted regions receiving strong solar radiation.
ISSN:1748-9326
1748-9326
DOI:10.1088/1748-9326/ab4872