This site uses cookies. By continuing to use this site you agree to our use of cookies. To find out more, see our Privacy and Cookies policy.
Skip to the content

[IOP] A community website from IOP Publishing

environmentalresearchweb blog

Oslo: frost flowers create a mercury bouquet

Frost flowers, the delicate structures that form on the surface of fresh sea ice, have been implicated in mercury depletion events – the drop in atmospheric mercury levels at the poles in springtime. Now researchers have come up with a potential mechanism for how the flowers take up mercury.

Speaking at the IPY Oslo Science Conference, Jody Deming of the University of Washington, US, explained how she and her colleagues discovered microbes living in the frost flowers, the first indication that the structures can support organisms. It’s protective exopolymers secreted by these bacteria that absorb the mercury.

Deming doesn’t think that anyone had looked for microbiology inside frost flowers before because of their extreme conditions – low temperatures (frost flowers form at temperatures of less than –8 °C), high salinity due to the expulsion of brine as the sea ice freezes below, high ultraviolet levels, and a brief lifetime before being dispersed by wind or squashed beneath snow.

As part of Canada’s Circumpolar Flaw Lead project, the team found lots of frost flowers, with dendrites 3–5 cm long, on thin ice in December 2007 and January 2008. Epifluorescence spectroscopy revealed the presence of microbes. What’s more, when the team grew frost flowers in the laboratory it found that the saltier the frost flower, the more bacteria it contained. It seems that bacteria are forced out of sea ice as it freezes, alongside salt. “Bacteria are impurities just like brine is,” said Deming.

Exopolymer concentrations in the frost flowers were 26 times higher than in sea ice. These gelatinous substances are secreted by microbes to help protect them from dessication, freezing and heavy metals. The polymer binds to the metal; it’s this action that the researchers believe is causing frost flowers to adsorb mercury during depletion events.

A paper on the work is in press at Geophysical Research Letters.

This entry was posted in IPY Oslo Science Conference and tagged , . Bookmark the permalink.
View all posts by this author 

Leave a comment

Your e-mail address will not be published.


  • Comments should be relevant to the article and not be used to promote your own work, products or services.
  • Please keep your comments brief (we recommend a maximum of 250 words).
  • We reserve the right to remove excessively long, inappropriate or offensive entries.

Show/hide formatting guidelines

Tag Description Example Output
<a> Hyperlink <a href="">google</a> google
<abbr> Abbreviation <abbr title="World Health Organisation" >WHO</abbr> WHO
<acronym> Acronym <acronym title="as soon as possible">ASAP</acronym> ASAP
<b> Bold <b>Some text</b> Some text
<blockquote> Quoted from another source <blockquote cite="">IOP</blockquote>
<cite> Cite <cite>Diagram 1</cite> Diagram 1
<del> Deleted text From this line<del datetime="2012-12-17"> this text was deleted</del> From this line this text was deleted
<em> Emphasized text In this line<em> this text was emphasised</em> In this line this text was emphasised
<i> Italic <i>Some text</i> Some text
<q> Quotation WWF goal is to build a future <q cite="">
where people live in harmony with nature and animals</q>
WWF goal is to build a future
where people live in harmony with nature and animals
<strike> Strike text <strike>Some text</strike> Some text
<strong> Stronger emphasis of text <strong>Some text</strong> Some text