Research output: Contribution to journal › Article › peer-review
The strong activity of noctilucent clouds at middle latitudes in 2020. / Dalin, Peter; Suzuki, Hidehiko; Pertsev, Nikolay et al.
In: Polar Science, Vol. 35, 100920, 01.03.2023.Research output: Contribution to journal › Article › peer-review
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TY - JOUR
T1 - The strong activity of noctilucent clouds at middle latitudes in 2020
AU - Dalin, Peter
AU - Suzuki, Hidehiko
AU - Pertsev, Nikolay
AU - Perminov, Vladimir
AU - Shevchuk, Nikita
AU - Tsimerinov, Egor
AU - Zalcik, Mark
AU - Brausch, Jay
AU - McEwan, Tom
AU - McEachran, Iain
AU - Connors, Martin
AU - Schofield, Ian
AU - Dubietis, Audrius
AU - Černis, Kazimieras
AU - Zadorozhny, Alexander
AU - Solodovnik, Andrey
AU - Lifatova, Daria
AU - Grønne, Jesper
AU - Hansen, Ole
AU - Andersen, Holger
AU - Melnikov, Dmitry
AU - Manevich, Alexander
AU - Gusev, Nikolay
AU - Romejko, Vitaly
N1 - Funding Information: The authors are grateful to all observers for their help in observing noctilucent clouds in Japan, Canada, USA, Europe and Russia. The NLC photograph taken from Hokkaido has been provided by a staff of Nayoro astronomy observatory, Mr. Fumitake Watanabe. This work was supported in part by the Japan Society for the Promotion of Science (JSPS) KAKENHI (Grant No. JP19H01956), by Meiji University (Grant No. MU-RMG 2019–21), by the Russian Foundation for Basic Research (Grant No. 19-05-00358a) and by the Science Committee of the Ministry of Education and Science of the Republic of Kazakhstan (Grant No. АРО8856096). We thank the Aura/MLS team for providing high-quality temperature and water vapor data. Publisher Copyright: © 2022
PY - 2023/3/1
Y1 - 2023/3/1
N2 - The 2020 summer season had more frequent than usual occurrences of noctilucent clouds (NLCs) in the Northern Hemisphere at middle latitudes (45–50°N), with the lowest latitude at which NLCs were seen being 34.1°N. In order to investigate a reason for this extraordinary NLC season, we have analyzed long-term Aura/MLS satellite data for all available summer periods from 2005 to 2021. Both Aura/MLS summer temperature and water vapor in the mesopause region, between about 79 and 89 km altitude, have been considered. There has been a decrease in the summer mesopause temperature between 2016 and 2020. At the same time, water vapor mixing ratio has significantly increased (by about 12–17%) in the zonal mean H2O value in the 2020 summer compared to 2017. There exists a positive linear trend in the H2O amount by about 5% between 2005 and 2021 at middle latitudes 45–50°N at 0.0046 hPa. A combination of lower mesopause temperature and water vapor mixing ratio maximum at middle latitudes is the main reason for frequent and widespread occurrences of NLCs seen around the globe at middle latitudes in the summer of 2020. The 24th solar cycle minimum can explain neither the H2O maximum nor NLC maximum in 2020.
AB - The 2020 summer season had more frequent than usual occurrences of noctilucent clouds (NLCs) in the Northern Hemisphere at middle latitudes (45–50°N), with the lowest latitude at which NLCs were seen being 34.1°N. In order to investigate a reason for this extraordinary NLC season, we have analyzed long-term Aura/MLS satellite data for all available summer periods from 2005 to 2021. Both Aura/MLS summer temperature and water vapor in the mesopause region, between about 79 and 89 km altitude, have been considered. There has been a decrease in the summer mesopause temperature between 2016 and 2020. At the same time, water vapor mixing ratio has significantly increased (by about 12–17%) in the zonal mean H2O value in the 2020 summer compared to 2017. There exists a positive linear trend in the H2O amount by about 5% between 2005 and 2021 at middle latitudes 45–50°N at 0.0046 hPa. A combination of lower mesopause temperature and water vapor mixing ratio maximum at middle latitudes is the main reason for frequent and widespread occurrences of NLCs seen around the globe at middle latitudes in the summer of 2020. The 24th solar cycle minimum can explain neither the H2O maximum nor NLC maximum in 2020.
KW - Noctilucent clouds
KW - Solar activity
KW - Summer mesopause
UR - http://www.scopus.com/inward/record.url?scp=85143881654&partnerID=8YFLogxK
UR - https://www.mendeley.com/catalogue/8d77d8c9-f008-3cbc-a903-26f8942c9ed9/
U2 - 10.1016/j.polar.2022.100920
DO - 10.1016/j.polar.2022.100920
M3 - Article
AN - SCOPUS:85143881654
VL - 35
JO - Polar Science
JF - Polar Science
SN - 1873-9652
M1 - 100920
ER -
ID: 40859105