During that recent giant snowstorm that blew over and the through the Mid Atlantic seaboard, I was home, hoping the power would not go out.
Also, too, I was surfing the web looking at snow pics. yeah...
You might be thinking – “CQ, why look on line? Really, you have to simply step outside your home to find gobs of snow?” And you’d be right in thinking that. I did go out and enjoyed tramping around on fresh snow, but honestly, what I was looking for was some icicles.
We had some small ones and I wanted to see the really BIG ones. Yes, I know they can damage roofs. But I had only the small ones.
I wanted to see the huge ones on waterfalls and trees and on the beaches. I was seeking the really spectacular ones.
While looking through amazing pictures of icicles, I ran up against a picture of a brinicle.
What is a brinicle, you ask?
Yes, well, follow me below Itzl.
As you can see by Itzl's concerned look, this group is for us to check in. As you can see by
Itzl's concerned look, this group is for us to check in at to let people know we are alive, doing OK, and not affected by such things as heat, blizzards, floods wild fires, hurricanes, tornadoes, power outages, or other such things that could keep us off DKos. It's also so we can find other Kossacks nearby for in-person checks when other methods of communication fail - a buddy system. Members come here to check in. If you're not here, or anywhere else on DKos, and there are adverse conditions in your area (floods, heatwaves, hurricanes, etc.), we and your buddy are going to check up on you. If you are going to be away from your computer for a day or a week, let us know here. We care!
We have split up the publishing duties, but we welcome everyone in IAN to do daily diaries for the group! Every member is an editor, so anyone can take a turn when they have something to say, photos and music to share, a cause to promote or news! If you would like to write a diary, let us know in a comment.
We have a current diary schedule. If you would like to fill in, either post in thread or send FloridaSNMom a Kosmail with the date. If you need someone to fill in, ditto. FSNMom is here on and off through the day usually from around 9:30 or 10 am eastern to around 11 pm eastern.
We are looking for a new writer to take over our regular Saturday diary. Please kosmail — weck or FloridaSNMOM, or one of the links below, if you are interested.
A brinicle is an ice stalactite which forms beneath sea ice. They form in the waters of the Arctic and the Antarctic.
It has also been called an “underwater icicle of death.” Brrr. Sounds chilly, doesn’t it?
A brinicle is an icicle that sinks down to the seabed. As it sinks down, a web of ice spreads out from it, killing urchins and starfish and other small marine life-forms.
Brinicles are formed in a process whereby salt water is excluded from the sinking sea ice. The brine is denser and colder than the freezing point of the sea water and it sinks to the bottom in a plume. It is sinking brine which causes the water to freeze around it like a sheath. These icicles are not like the ones in our freezer or the ones forming off our roofs which are solid frozen lumps. No, the brinicle is different in that:
Instead of a solid dense lump, it is more like a seawater-soaked sponge with a tiny network of brine channels within it.
Brinicle is sea stalactite which projects downwards from the frozen surface of the sea towards into
the seabed:
In winter, the air temperature above the sea ice can be below -20C, whereas the sea water is only about -1.9C. Heat flows from the warmer sea up to the very cold air, forming new ice from the bottom. The salt in this newly formed ice is concentrated and pushed into the brine channels. And because it is very cold and salty, it is denser than the water beneath.
Evidently, the air aloft the sea is colder than the warmer water on the surface of the sea. when the
sea comes in contact with the air it begins to form ice from the bottom. As heat flows up and comes into continuous contact with the forming ice, it continues to form more ice from the bottom. As this cooling process continues, the sea water ejects salt and it begins to concentrate as brine.
This concentrate, in turn, increases the salinity of nearby water, which in turn lowers its freezing
point as more salt is released, forming pockets. Pockets of brine gets trapped inside ice packs. The ice pack cracks and the brine – which is colder, heavier and denser than the surrounding water, sinks down, freezing any fresh sea water it comes in contact with, thereby forming a salty, icy tube – a brinicle.
When the column of the brinicle gets to the sea bed, it expands and spreads, trapping and killing marine critters on the sea floor. Large Weddel Seals, on the other hand have no problems barging past the brinicles and even breaking them.
Brinicles need calm water conditions to grow downwards to the sea floor. Also, when the brine drains out of those ice pockets, leaving air behind, the salinity of the surface decreases and full freeze settles in, solidifying surface ice.
As an aside to this story about brinicles, there is this interesting fact:
The exchange of salt between sea ice and the ocean influences ocean circulation across hundreds of kilometers.
Here is a video which shows the concentrated brine flowing downward and freezing as a funnel.
I didn’t want to load a video showing marine animals being trapped and dying in the expanding brinicle. However, the video is available here, in case you want to see it. It is cool but kind of grisly.
Here is a still shot of the BBC cameras set up to photograph the brinicle growth for the Frozen Planet show.