TY - JOUR
T1 - The impacts of shipping emissions on lightning
T2 - roles of aerosol-radiation-interactions and aerosol-cloud-interactions
AU - Sun, Ruize
AU - Lu, Xiao
AU - Gao, Meng
AU - Du, Yu
AU - Lin, Haipeng
AU - Wright, Chris
AU - He, Cheng
AU - Yin, Ke
N1 - We thank the WWLLN (http://wwlln.net), a collaboration among over 50 universities and institutions, for providing the lightning data used in this paper. We thank Robert Holzworth for obtaining WWLLN data. We are grateful to Mary Barth for her valuable advice on lightning simulation. Xiao Lu acknowledges funding from the Guangdong Basic and Applied Basic Research project (Grant No. 2020B0301030004), the Guangdong Basic and Applied Basic Research Foundation (2022A1515011554), and the National Natural Science Foundation of China (Grant No. 42105103).
Publisher Copyright:
© 2024 The Author(s). Published by IOP Publishing Ltd
PY - 2024/2/27
Y1 - 2024/2/27
N2 - Long-term (2005-2021) observations from the World Wide Lightning Location Network reveal significantly larger flash counts over heavily trafficked shipping lanes in the northeastern Indian Ocean compared to nearby regions. Here, we use the online coupled meteorology-chemistry model WRF-Chem to examine the impact of aerosols from shipping emissions on lightning activity over one of the world’s busiest shipping lanes (5-7° N, 82-92° E). We conduct three case simulations in January 2013, 2015, and 2018 when frequent lightning activities were recorded. The WRF-Chem model with lightning parameterized based on convective cloud-top height captures the temporal evolution of lightning activities but overestimates the magnitude of lightning counts. We find that all three cases consistently show enhanced lightning flash counts due to shipping-induced aerosols by 6.2%-22.3%, accompanied by increased cloud droplet number, cloud water concentration, radar reflectivity, and cloud-top height. Sensitivity simulations show that aerosol-cloud-interactions from shipping aerosols consistently enhance the strength of convection and lightning frequency in all three cases, by increasing cloud condensation nuclei and cloud droplet numbers, delaying precipitation of cloud water, allowing the lift and accumulation of water vapor, increasing release of latent heat, and finally invigorating convections. In comparison, aerosol-radiation-interactions show inconsistent contributions to convection and lightning, which enhance lightning frequency in the 2013 and 2015 cases but decrease lightning frequency in the 2018 case. This inconsistency may be attributed to differences in the number and vertical structure of shipping aerosols and cloud droplet in the three cases. Our study thus approves the certain but complicated anthropogenic impacts on lightning activities through shipping-induced aerosols, which has important implications for understanding future trends in lightning and its impact on atmospheric chemistry and climate.
AB - Long-term (2005-2021) observations from the World Wide Lightning Location Network reveal significantly larger flash counts over heavily trafficked shipping lanes in the northeastern Indian Ocean compared to nearby regions. Here, we use the online coupled meteorology-chemistry model WRF-Chem to examine the impact of aerosols from shipping emissions on lightning activity over one of the world’s busiest shipping lanes (5-7° N, 82-92° E). We conduct three case simulations in January 2013, 2015, and 2018 when frequent lightning activities were recorded. The WRF-Chem model with lightning parameterized based on convective cloud-top height captures the temporal evolution of lightning activities but overestimates the magnitude of lightning counts. We find that all three cases consistently show enhanced lightning flash counts due to shipping-induced aerosols by 6.2%-22.3%, accompanied by increased cloud droplet number, cloud water concentration, radar reflectivity, and cloud-top height. Sensitivity simulations show that aerosol-cloud-interactions from shipping aerosols consistently enhance the strength of convection and lightning frequency in all three cases, by increasing cloud condensation nuclei and cloud droplet numbers, delaying precipitation of cloud water, allowing the lift and accumulation of water vapor, increasing release of latent heat, and finally invigorating convections. In comparison, aerosol-radiation-interactions show inconsistent contributions to convection and lightning, which enhance lightning frequency in the 2013 and 2015 cases but decrease lightning frequency in the 2018 case. This inconsistency may be attributed to differences in the number and vertical structure of shipping aerosols and cloud droplet in the three cases. Our study thus approves the certain but complicated anthropogenic impacts on lightning activities through shipping-induced aerosols, which has important implications for understanding future trends in lightning and its impact on atmospheric chemistry and climate.
KW - lightning
KW - convections
KW - aerosol-cloud-interactions
KW - aerosol-radiation-interactions
KW - WRF-Chem
UR - http://www.scopus.com/inward/record.url?scp=85186115468&partnerID=8YFLogxK
U2 - 10.1088/1748-9326/ad2aba
DO - 10.1088/1748-9326/ad2aba
M3 - Journal article
AN - SCOPUS:85186115468
SN - 1748-9326
VL - 19
JO - Environmental Research Letters
JF - Environmental Research Letters
M1 - 034038
ER -
