Bacteria creates hail stones - study

2011-05-25 09:39
Washington - Hail storms seem to arise out of nowhere, leaving those pummelled by the coin- to fist-sized ice balls to wonder how they came to be. US scientists said on Tuesday that plant bacteria may be to blame.

A Montana scientist collected some large hailstones measuring more than 5cm in diameter after a June storm in 2010, froze them, and later analysed the water that melted away in layers.

"Bacteria have been found within the embryo, the first part of a hailstone to develop," said Alexander Michaud of Montana State University in Bozeman, who presented the research at a meeting of microbiologists in New Orleans.

"The embryo is a snapshot of what was involved with the event that initiated growth of the hailstone," said Michaud, a lead researcher in the field of bioprecipitation, the study of how bacteria may cause rain, snow and hail.

In order for clouds to make ice, from which snow can fall, a particle must be present for the ice crystals to grow around, known as an ice nucleus.


"In order for precipitation to occur, a nucleating particle must be present to allow for aggregation of water molecules," said Michaud.

"There is growing evidence that these nuclei can be bacteria or other biological particles."

A plant pathogen known as Psuedomonas syringae is commonly at the root of precipitation events, because its outer surface is so efficient at collecting water molecules around it, said Brent Christner of Louisiana State University.

"Ice nucleating strains of P. syringae possess a gene that encodes a protein in their outer membrane that binds water molecules in an ordered arrangement," said Christner, who also presented research at the American Society for Microbiology in New Orleans.

This provides "a very efficient nucleating template that enhances ice crystal formation", said Christner.

Join the conversation! encourages commentary submitted via MyNews24. Contributions of 200 words or more will be considered for publication.

We reserve editorial discretion to decide what will be published.
Read our comments policy for guidelines on contributions.
Read more on:    research  |  weather

linking and moving

2015-04-22 07:36 publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
Comments have been closed for this article.

Inside News24


Rugby World Cup 2015

All the action from the 2015 RWC, including live coverage of all 48 matches, breaking news, fixtures, results, logs - and much more!


Rugby World Cup 2015

Ratings: Habana thrives in rout
LIVE: Namibia 16-17 Georgia
Meyer hails Habana
Boks thrash USA, Habana level with Lomu
Traffic Alerts

Relationships and significant connections may play an important role in your day today. Let the warmth of the Leo moon inspire more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.