Assessing Arctic low-level clouds and precipitation from above – a radar perspective

Schirmacher, Imke; Kollias, Pavlos; Lamer, Katia; Mech, Mario; Pfitzenmaier, Lukas; Wendisch, Manfred; Crewell, Susanne

doi:https://doi.org/10.5194/amt-16-4081-2023

Articles | Volume 16, issue 17

https://doi.org/10.5194/amt-16-4081-2023

© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Special issue:

HALO-(AC)³ – an airborne campaign to study air...

https://doi.org/10.5194/amt-16-4081-2023

© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Articles | Volume 16, issue 17

Research article

|

11 Sep 2023

Research article |

| 11 Sep 2023

Assessing Arctic low-level clouds and precipitation from above – a radar perspective

Imke Schirmacher, Pavlos Kollias, Katia Lamer, Mario Mech, Lukas Pfitzenmaier, Manfred Wendisch, and Susanne Crewell

Data sets

The ERA5 global reanalysis H. Hersbach, B. Bell, P. Berrisford, S. Hirahara, A. Horányi, J. Muñoz-Sabater, J. Nicolas, C. Peubey, R. Radu, D. Schepers, A. Simmons, C. Soci, S. Abdalla, X. Abellan, G. Balsamo, P. Bechtold, G. Biavati, J. Bidlot, M. Bonavita, G. De Chiara, P. Dahlgren, D. Dee, M. Diamantakis, R. Dragani, J. Flemming, R. Forbes, M. Fuentes, A. Geer, L. Haimberger, S. Healy, R. J. Hogan, E. Hólm, M. Janisková, S. Keeley, P. Laloyaux, P. Lopez, C. Lupu, G. Radnoti, P. de Rosnay, I. Rozum, F. Vamborg, S. Villaume, and J.-N. Thépaut https://doi.org/10.1002/qj.3803

Radar reflectivities at 94GHz and microwave brightness temperature measurements at 89GHz during the ACLOUD Arctic airborne campaign in early summer 2017 out of Svalbard M. Mech, N. Risse, S. Crewell, and L.-L. Kliesch https://doi.org/10.1594/PANGAEA.945988

Cloud top altitude retrieved from Lidar measurements during ACLOUD at 1 second resolution B. S. Kulla, M. Mech, N. Risse, and C. Ritter https://doi.org/10.1594/PANGAEA.932454

Cloud top altitude retrieved from Lidar measurements during AFLUX at 1 second resolution B. S. Kulla, M. Mech, N. Risse, and C. Ritter https://doi.org/10.1594/PANGAEA.932455

AMSR2 ASI sea ice concentration data, Arctic, version 5.4 (NetCDF) (July 2012–December 2019) C. Melsheimer and G. Spreen https://doi.org/10.1594/PANGAEA.898399

Model code and software

Ac3airborne M. Mech, N. Risse, G. Marrollo, and D. Paul https://doi.org/10.5281/zenodo.7305585

Short summary

CloudSat’s relatively coarse spatial resolution, low sensitivity, and blind zone limit its assessment of Arctic low-level clouds, which affect the surface energy balance. We compare cloud fractions from CloudSat and finely resolved airborne radar observations to determine CloudSat’s limitations. Cloudsat overestimates cloud fractions above its blind zone, especially during cold-air outbreaks over open water, and misses a cloud fraction of 32 % and half of the precipitation inside its blind zone.