Measurements of bubble size spectra within leads in the Arctic summer pack ice 1School of Earth and Environment, University of Leeds, Leeds, UK
14 Feb 2011
2Finnish Meteorological Institute, Climate and Global Change Unit, Helsinki, Finland
3University of Helsinki, Department of Physics, Helsinki, Finland
4TNO, Utrecht, The Netherlands
5Geophysical Institute, University of Bergen, Norway
6Bjerknes Centre for Climate Research, Bergen, Norway
7Department of Meteorology, Stockholm University, Sweden
8Bert Bolin Centre for Climate Research, Stockholm University, Stockholm, Sweden
Received: 21 September 2010 – Published in Ocean Sci. Discuss.: 04 October 2010 Abstract. The first measurements of bubble size spectra within the near-surface waters
of open leads in the central Arctic pack ice were obtained during the Arctic
Summer Cloud-Ocean Study (ASCOS) in August 2008 at 87–87.6° N,
1–11° W. A significant number of small bubbles (30–100 μm
diameter) were present, with concentration decreasing rapidly with size from
100–560 μm; no bubbles larger than 560 μm were observed. The
bubbles were present both during periods of low wind speed (U<6 m s−1) and when ice covered the surface of the lead. The low wind and
short open-water fetch precludes production of bubbles by wave breaking
suggesting that the bubbles are generated by processes below the surface.
When the surface water was open to the atmosphere bubble concentrations
increased with increasing heat loss to the atmosphere. The presence of
substantial numbers of bubbles is significant because the bursting of
bubbles at the surface provides a mechanism for the generation of aerosol
and the ejection of biological material from the ocean into the atmosphere.
Such a transfer has previously been proposed as a potential climate feedback
linking marine biology and Arctic cloud properties.
Revised: 01 February 2011 – Accepted: 02 February 2011 – Published: 14 February 2011
Citation: Norris, S. J., Brooks, I. M., de Leeuw, G., Sirevaag, A., Leck, C., Brooks, B. J., Birch, C. E., and Tjernström, M.: Measurements of bubble size spectra within leads in the Arctic summer pack ice, Ocean Sci., 7, 129-139, doi:10.5194/os-7-129-2011, 2011.