Lidar observations of cirrus clouds in Palau (7°33′ N, 134°48′ E)
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Published:2021-05-25
Issue:10
Volume:21
Page:7947-7961
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ISSN:1680-7324
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Container-title:Atmospheric Chemistry and Physics
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language:en
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Short-container-title:Atmos. Chem. Phys.
Author:
Cairo FrancescoORCID, De Muro Mauro, Snels MarcelORCID, Di Liberto Luca, Bucci SilviaORCID, Legras BernardORCID, Kottayil Ajil, Scoccione AndreaORCID, Ghisu Stefano
Abstract
Abstract. A polarization diversity elastic backscatter lidar was deployed on the equatorial island of Palau in February and March 2016 in the framework of the EU StratoClim project. The system operated unattended in the Palau Atmosferic Observatory from 15 February to 25 March 2016 during the nighttime. Each lidar profile extends from the ground to 30 km height. Here, the dataset is presented and discussed in terms of the temperature structure of the upper troposphere–lower stratosphere (UTLS) obtained from co-located radiosoundings. The cold-point tropopause (CPT) was higher than 17 km. During the campaign, several high-altitude clouds were observed, peaking approximately 3 km below the CPT. Their occurrence was associated with cold anomalies in the upper troposphere (UT). Conversely, when warm UT anomalies occurred, the presence of cirrus was restricted to a 5 km thick layer centred 5 km below the CPT. Thin and subvisible cirrus (SVC) were frequently detected close to the CPT. The particle depolarization ratios of these cirrus were generally lower than the values detected in the UT clouds. CPT cirrus occurrence showed a correlation with cold anomalies likely triggered by stratospheric wave activity penetrating the UT. The back-trajectories study revealed a thermal and convective history compatible with the convective outflow formation for most of the cirrus clouds, suggesting that the majority of air masses related to the clouds had encountered convection in the past and had reached the minimum temperature during its transport in less than 48 h before the observation. A subset of SVC with low depolarization and no sign of significative recent uplifting may have originated in situ.
Publisher
Copernicus GmbH
Subject
Atmospheric Science
Reference80 articles.
1. Biavati, G., Di Donfrancesco, G., Cairo, F., and Feist, D. G.: Correction
scheme for close-range lidar returns, Appl. Opt., 50, 5872–5882, 2011. a 2. Bissonnette, L. R.: Lidar and multiple scattering, in: Lidar,
Springer, 43–103, 2005. a 3. Boehm, M. T. and Verlinde, J.: Stratospheric influence on upper tropospheric
tropical cirrus, Geophysical Res. Lett., 27, 3209–3212, 2000. a 4. Bucci, S., Cristofanelli, P., Decesari, S., Marinoni, A., Sandrini, S., Größ, J., Wiedensohler, A., Di Marco, C. F., Nemitz, E., Cairo, F., Di Liberto, L., and Fierli, F.: Vertical distribution of aerosol optical properties in the Po Valley during the 2012 summer campaigns, Atmos. Chem. Phys., 18, 5371–5389, https://doi.org/10.5194/acp-18-5371-2018, 2018. a 5. Bucci, S., Legras, B., Sellitto, P., D'Amato, F., Viciani, S., Montori, A., Chiarugi, A., Ravegnani, F., Ulanovsky, A., Cairo, F., and Stroh, F.: Deep-convective influence on the upper troposphere–lower stratosphere composition in the Asian monsoon anticyclone region: 2017 StratoClim campaign results, Atmos. Chem. Phys., 20, 12193–12210, https://doi.org/10.5194/acp-20-12193-2020, 2020. a
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