Candle Ice

Alas, when I checked the ice late this afternoon, it was too soft to walk on.  This morning my pole barely dented the ice when I whacked it - this afternoon it went through with little effort.  This is at the shoreline...I'm sure it is still solid further out. I just can't get there.

So, I'm a little sad that I can't walk on the lake anymore, and a little relieved.

 

This photo is a close-up of the candle ice from this morning.  The little round bits are about a quarter inch diameter. In the bigger pictures, this would be the 'black' ice.  Not all the ice on the lake has candled.  The pale ice is honeycombed, and stronger.

 

This afternoon the black ice within a hundred feet of land went white, as it finally melted away from shore and lifted.  It will go black again just before it's gone.

 

Warm days and south winds will have a big impact on the ice.  Still, there's no telling how long it will take. A week?  

The ice I walked on in the middle of the lake this morning was thick, and hard.  It's going to take some time.

Ice

Is the ice safe? Yes. I only know this because I'm out there walking on it every day. And because I know my lake. I would not walk on a lake I did not know at this time of melt.
99% of the lake has solid ice. I don't walk on the 1% that is not safe. And, I avoid another 5% that is near the ice that is unsafe. Still, I carry a long pole that would keep me from going all the way in if I did make a mistake.
I work very hard at not making a mistake.
My experience from many years of ice walking is that I must listen to my inner voice - which often cautions me. The few times I have made mistakes is when my desire to get somewhere overrode my inner cautious self.

We don't get wiser just because we get older...we only get older if we get wiser.

Pure beauty

Near the large pressure crack, this 'pool'.  At the edge of the pool, lace.

 

the far shore

This is where one of the major pressure cracks meets the far shore.  The ice I walked on to get there is well over a foot thick, and hard as ever...right up to the edge of the crack, and right up to the bedrock shoreline.  A skim of ice formed on the open water overnight, and was starting the crack again this morning. 

I will admit to more than a little adrenaline hitting my heart when a loud crack snapped right underfoot.  The fear only lasted a moment, because there is no way the ice can break right now. 

In some of the ice art photos below you can see these hairline cracks.  As I walk across the ice, I am fascinated by the various textures, and reassured by the depth of the cracks...which continuously assure me that the ice is more than 8 inches thick.

ice art

How thick is it?

The ice I walked on this morning was generally 7 to 12 inches thick. Except near shore, of course, where it thinned out to nothing at all.
How do I know that it is safe? I take great care, and I carry a long pole that serves as a poking stick. When I want to check any particular patch of ice, I give it a number of sharp whacks with the end of the pole. Most of the time, it barely makes a dent in the surface. Sometimes, just a few whacks will break through.
The colour of the ice gives some indication of strength. In this photo, the dark ice broke though with about 4 pokes. Yet, I could not poke a hole all the way through the paler ice a foot away. The ice at this spot was about 4 inches thick.

Colour alone is not an indicator of the quality of the ice. Some pale ice I walked on just a little closer to shore had a 'soft' feel as I stepped on it. It whispered to me, a little creeeek. I did not poke a hole there...no point making it weaker while I was standing on it! I went back to the quiet ice, and found a better place to walk back to the land.

Monday mornng

The beauty of the ice draws me out each day.  These photos are all of the same pressure crack, which includes a wide open water space at a rocky shoal. 

back to land....

This is where we stepped back onto the land at the end of our journey.  Normally, the ice would be tight to this point.  But this year, the pressure of the expanding ice last week pushed the ice against the shore, and some of it submerged, then melted.  We found a narrow patch of ice on the left side that was still tight to the rock.

Last crossing

Kate pulls the canoe across the pressure crack in the middle of the lake.  As you see in some of the other photos, these cracks are very beautiful. The ice shrinks and pulls apart, then the water in the cracks freezes, and the pressure builds again as the ice expands. 

Sometimes that expansion causes pressure enough to make the ice buckle.  It rises on one side of the crack, and dips on the other side.  And these up and down places ripple along the crack. The ice that gets pushed down melts faster, sometimes creating large pools of water surrounded by thick ice.

 

 

Pressure crack close-ups

Last crossing

Making the decision for when the last crossing of the ice will be is always difficult.  Is it safe?  Will it be safe tomorrow?  Or, how about if we just go now?

 

Kate and I decided to go late Sunday afternoon.  We could have taken the snowmachine...there was lots of ice.  The problem with driving across the lake is that you don't get to see very much.  You don't get a good feel for the ice.  And perhaps if the ice did something weird that it has never done before that might be a problem...you don't know that until it's too late. 

 

We took the canoe along as a sled for our stuff. and to act as a bridge just in case we came to a pressure crack that we weren't comfortable crossing.

Presure crack day 2

Ice patterns

This is the ski pole we poke through holes in the ice to see how thick it is. We started measuring when the ice was over 18 inches thick. Today, March 28th, the ice varies from 4 to 15 inches....except on the sunny shorelines, where there is no ice at all....

Pressure crack!

This is a view of the pressure crack in the middle of the lake 4 days after it was first pictured on March 22nd (below).

Break-up 2010

The day after the pressure crack/ridge formed by the Island.  The black spot in the middle ice-free.

The water under the ice is 'warm', so submerged ice melts quickly.

 

 

Break-up 2010

Following the long stretch of warm weather we had for most of March, the night time temperature dropped to -16 one night.  It is the extreme temperature changes that make the ice stretch and shrink...and thus pressure cracks result. 

 

I took a walk on the ice the next morning.  The Kukagami Loch-ness monster was roaring!  Crack and clump, ripping cracks continued to go everywhere.  But the ice had nowhere to move.  so it groaned and complained.  Then it rose along this crack between the Island and the shore in front of the lodge.

 

It had to bend on the lake-ward side, because the ice stretched more than could fit between the shores.

The crack on the right has risen about a foot above the rest of the ice, and the dip has sunk more than a foot below the water level.

 

You can see the stress lines under the water.

Break-up 2010

As I walked across the lake on March 22nd, I looked for this former pressure crack. When the ice was new in December, varying temperatures caused the ice to crack and lift slightly here. I thought the spring ice would crack here again, but it has not.

Break-up 2010

Close-up of the pressure crack.  You can see where it opened a bit, then refroze.

Break-up 2010

I walked across the lake on the afternoon of Monday, March 22nd.  This pressure crack crossed the lake from east to west.  I crossed several more pressure cracks along my 6 km hike. 

ice patterns

 

Break-up 2010

This is a close-up of the place where the ice froze early in December and got snowed on (white).  The dark ice came a few days after the snow, thus shows clear.

Break-up 2010

With all the snow long gone from the lake, the clear ice allows a view of the rock below.  Reminiscent of the same area from last December (below).

Clear Ice with rocks from December

 

Break-up 2010

What an odd end to winter we've had!  Warm weather arrived in the first few days of the month, and stayed for nearly 3 weeks.  It didn't take long for the snow to melt away, and soon the ice began to melt.

 

This has never happened in March before.  Actually it doesn't get that warm for that long even in April.  So we've been watching very closely this year.  The melt is different than I've ever seen before, but ever so beautiful.

 

This close-up of the ice surface on March 22nd shows the clarity, and the beginnings of melt lines.