Thinking about Sea Ice and Model Predictions

My sense is that the global climate models (GCM) have generally done a poor job of projecting loss of sea ice and I think this is important because the change in albedo with loss of sea ice is a positive feedback that could trigger other positive feedback loops (like release of CO2 and CO2e gases from permafrost, ocean floor, etc.)

So, I am searching a little to see if my sense about the GCM sloppiness on sea ice is correct.  Here is what I find:

at Arctic Deeply:

“In September 2007, Arctic sea ice levels reached a dramatic and unexpected new low, tumbling to 4.154 million square kilometers (1.6 million square miles) – roughly 40 percent smaller than what it had been in the 1980s. Summer sea ice melt was far outpacing the models produced by scientists, prompting scientists to join together internationally to produce monthly reports on the anticipated state of the Arctic sea ice based on their individual assessments.”  (emphasis added).

So, the models were not doing a good job in 2007 and the scientists jumped in to improve the models and predictions.  Then I find this article in Carbon Brief from 2014:

Why aren’t climate models better at predicting Arctic sea ice loss?

Looks like they had not gotten a lot better from 2007 to 2014.

On current state of sea ice loss science, I find the following websites that may be accurate and informative:

Sea Ice Prediction Network

Arctic Sea Ice Predictions

But the bottom line still appears to be that the models can only be fairly accurate if they are initiated on a monthly basis, so I think that indicates the complexity and dynamic nature of sea ice loss is just beyond our GCM models absent a monthly reset to correct to observed conditions.  Maybe I have this wrong?

Rocket mass heater Part 5

5 Rocket Stove 2015Dec18 (14)

The burnstack is firebrick, wrapped in 1 inch unitherm ceramic insulation. The unitherm insulation is held in place by a couple of strands of wire, then I wrapped with metal mesh that is used for stucco. I think this is good to go, but need to decide if I need to clad the stack in fireclay. The fireclay mix would adhere nicely to the metal mesh and might protect the metal mesh, but I am not sure if this step is necessary.

5a Rocket Stove 2015Dec18 (12)

another look at the burn stack, this time looking down at top before I wrapped with the metal mesh.

5b Rocket Stove 2015Dec18 (8)

Cleanout at the beginning of the run back toward the burn chamber.  The fan idea is gone.

5c Rocket Stove 2015Dec18 (7)

Wrapping with left over unitherm, then moving back to build up with fireclay and cob mix.

You can see the ductwork/riser to left and behind the burnstack.  It will come out of the cob with a heavy 8 inch single wall stove pipe, then reduce down to 7 inch black stove pipe and runs about 5 feet back and slightly up before it does a 90 degree turn and into the brick chimney flue.

Rocket Mass Heater, Part 3


Got our bricks.

Thank you to Shawn and Amanda for taking a drive to Eugene to pick these up

These are not the dense heavy firebricks that I was expecting, but the lighter insulating firebrick.  These are supposed to be easy to cut with chisel or hacksaw.  I am going to need to do a little research and make sure the characteristics of these bricks are suitable for the rocket stove.  It seems like they should work, they will allow the heat to build inside the chamber and they should not absorb much of that heat.  I think that works because I want the heat to travel through the j-tube, build to high temperature in the riser/barrel and then I want the heat to transfer to the thermal mass before the exhaust exits the building.

I started laying out the bricks and thinking about brick count, how to construct the J tube, the heat riser, the support for the barrel and the ash cleanout.  Here are some pictures:

The bricks here are set on top of the poly iso foam board.

I don’t think that’s going to work.  The weight is going to deform the foam board. All of the foam board ideas are gone.

I was mainly just laying out the burn chambers and stacking brick to see how the rocket stove will fit in the space.  I really wanted to light up some paper and see if the rocket stove would draw as it is set up here, but I resisted the impulse.  I don’t think we are ready for that step yet.


The picture above shows the heat riser extended up a bit so that the top of the heat riser would be about 2 inches below the top of the barrel. I also played around a bit creating an ash cleanout pit.  That is the the rectangular space in the foreground of the picture above.  The ducting would then come out of the ash cleanout cavity,  run forward toward the position of the photographer in this picture (thanks for camera work, Marylea) then it will turn 180, run back and end in a stack that will rise and go out the “window” space just above the rocket stove.  I am going with the stack up and out of the mass heater in close proximity to the heat riser as Ernie and Erica have suggested.

bricks barrel

Here is a picture of the rocket stove with the barrel lifted and in place over the heat riser.  (pretty barrel, right?  need to spray that down with some bbq high temperature paint)

I think I will have to bring the whole rocket stove forward at least a foot so that I can get 2 feet of clearance between the barrel (that is going to get very hot) and the frame wall behind the stove and the ceiling above the barrel.

I think I will end up with a fireproof material on the walls near the barrel and on the ceiling above the barrel.  I am thinking about durock board, then maybe I end up with tile on wall behind or maybe just a cob type plaster.

Question for today:

  • Am I going to need to “glue” the bricks together with a firebrick mortar or cement or will I be able to mix a cement/cob material with vermiculite and seal the burn chamber, the j tube, the heat riser and the ash cleanout?

Going slow.  Having fun laying out this project.  We have been thinking about this for a long time.

It will be a few days before I can get back to this project.  I get my first day of jury duty tomorrow and also need to get back to the office grind for a reasonable number of hours.  Words need processing, phones need answering.