TY - JOUR
T1 - Enhanced heating rate of black carbon above planetary boundary layer over megacities in summertime
AU - Liu, Dantong
AU - Zhao, Delong
AU - Xie, Zhenzhen
AU - Yu, Chenjie
AU - Chen, Ying
AU - Tian, Ping
AU - Ding, Shuo
AU - Hu, Kang
AU - Lowe, Douglas
AU - Liu, Quan
AU - Zhou, Wei
AU - Wang, Fei
AU - Sheng, Jiujiang
AU - Kong, Shaofei
AU - Hu, Dawei
AU - Wang, Zhenzhu
AU - Ding, Deping
PY - 2019/11/18
Y1 - 2019/11/18
N2 - 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 3-5, and the coatings on the 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 the 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 the polluted regions receiving strong solar radiation.
AB - 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 3-5, and the coatings on the 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 the 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 the polluted regions receiving strong solar radiation.
UR - https://puretest.lancaster.ac.uk/portal/en/publications/enhanced-heating-rate-of-black-carbon-above-planetary-boundary-layer-over-megacities-in-summertime(37017fa1-01a2-4238-990e-6f33d2800675).html
U2 - 10.1088/1748-9326/ab4872
DO - 10.1088/1748-9326/ab4872
M3 - Article
SN - 1748-9326
JO - Environmental Research Letters
JF - Environmental Research Letters
ER -