EGU General Assembly 2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.

The Southern Ocean Cloud project

Tom Lachlan-Cope, Amelie Kirchgaessner, Anna Jones, Jo Browse, David Topping, Ferracci Valeria, Neil Harris, Floortje Van Den Heuval, Ian Renfrew, Jonathan Witherstone, Keith Bower, Daniel Partridge, and Thomas Bracegirdle
Tom Lachlan-Cope et al.
  • British Antarctic Survey, Cambridge, United Kingdom of Great Britain – England, Scotland, Wales (

The Southern Ocean Cloud (SOC) project is funded by the UK Natural Environment Research Council to investigate clouds, particularly mixed-phase, in the Atlantic sector of the Southern Ocean and how aerosol sources and production control clouds properties. Here we aim to introduce the community to the project and any associated opportunities that might be available. At high Southern latitudes models are relatively poor at representing clouds and this has an impact on the energy balance and hence atmospheric and oceanic circulation both locally and globally. This project will investigate those processes that control cloud development and will concentrate on the aerosol that act as cloud nuclei, the source of these nuclei and how aerosol and microphysical processes are modelled.


It is planned to deploy instruments to the British Antarctic Survey (BAS) research stations Rothera and Bird Island research stations as well as on the BAS research vessel. These instruments will measure the aerosol size spectrum at all stations and in addition CCN and INP numbers, cloud properties (with a polarized lidar) and aerosol composition at Rothera. The instruments will be deployed for at least 3 years, although some instruments may be moved from Rothera to the ship for special observing periods.


In addition to the long-term measurements there will be two special observing periods (SOPs), the first in the 2022/23 Antarctic season will consist of a dedicated ship cruise and an airborne campaign using the BAS instrumented twin otter aircraft along with enhanced observations at the surface stations. The second SOP will also have enhanced observations at the surface stations along with an airborne campaign.


The observations will be backed up with a programme of aerosol, weather and climate modelling. The combination of modelling and observations should enable us to identify the major sources of cloud nuclei over the Southern Ocean, examine their role in cloud development, and improve the representation of these processes in models.


How to cite: Lachlan-Cope, T., Kirchgaessner, A., Jones, A., Browse, J., Topping, D., Valeria, F., Harris, N., Van Den Heuval, F., Renfrew, I., Witherstone, J., Bower, K., Partridge, D., and Bracegirdle, T.: The Southern Ocean Cloud project, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9998,, 2021.


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