• Overground/underground - a caving archaeology project in the Yorkshire Dales

    1st June 2-4pm at Dales Countryside Museum in Hawes.

    Click here for more

Strange formation; any ideas?

Pitlamp

Well-known member
First thing this morning I brought the rain gauge in to thaw it out before taking the daily reading. Noticed this peculiar spike of ice sticking out. I thought at first some local kid had stuffed an icicle in but I'm pretty sure it's not that. (The surrounding ice surface curves up around the base of the spike.) If it was just an icicle it'd be leaning against the side but the spike is standing up on its own. Pretty sure it's actually grown out from the icy mush in the gauge as it froze overnight.

During yesterday we had a fair bit of snow, then sleet, then cold rain. Then from around midnight the skies cleared and there was a hard frost.

Anyone got any ideas how this strange ice spike might have formed?

RG_ice_170124_(1).jpeg
 

Pitlamp

Well-known member
Here's another picture from a different angle.

Meant to mention above; in the previous picture, notice the hollow along the middle of the ice formation, especially at the base. (Icicles don't have this.)

Incidentally, for those interested in underground conditions, although we had a lot of precipitation in the Dales yesterday (as you can see from the contents) it's not done much to river levels.

RG_ice_170124_(2).jpeg
 

Maj

Active member
From the Met Office- https://www.metoffice.gov.uk/weathe...spikes form as a,squeezed up through the hole.



Ice spikes form as a result of the way water freezes, from the outside in.

As the ‘skin’ of ice thickens, if a weakness or hole appears in the ice skin, the liquid water gets squeezed up through the hole.
The water that is squeezed out then forms the beginning of the spike and the process continues until the tip of the spike freezes.
For an ice spike to form, the air conditions need to be just right. It can’t be too cold or the water freezes too quickly, and a little breeze (but not too windy) helps the process.
 

Pitlamp

Well-known member
Thanks!

It's thawed out now and this morning's total is 22 mm. Cave divers might like to note that the improving vis lately has probably been set back somewhat (at least on the west side of the Dales).

If only last night's rain hadn't melted a lot of the snow . . . .
 

Pitlamp

Well-known member
Indeed. The mechanism which Maj described makes perfect sense.
In all the years of recording rainfall data on the CDG VisBot I've never had such a thing happen before. It's amazing how the ice spike grew so uniformly straight.
 

Pegasus

Administrator
Staff member
Fascinating. You learn something new every day.
I was just thinking that - every day is a school day.
Today I learnt as the oil level in your car starts to go down, it drops faster and faster - then my mechanic friend lost me with the explanation as to why 😁
 
Top