Days 23 & 24: Speed and
Melt of the Glacier
Up at 8 am. I felt
pretty good but beating a bacterial infection without antibiotics is a
long, painful road. I was at the doctor's office by 8:45. My appointment
wasn't until 9:30 am, but I was hoping the doctor might take pity
on me. He did, so I was able to meet the rest of the group and we headed
up to the terminal face of the glacier to do our measurements.
It may seem silly,
but I was so excited to actually see what happened with our two setups.
These aren't scientific experiments: no controls, treatments, etc.
Instead, we are making observations and measuring what we see very exciting
all the same. I wanted to run to the terminal face and round the corner
just to see if there were sticks on the ground, having melted out of the
glacier. Logically, I knew that at least one stick, representing a two-centimeter
melt, would be on the ground, but I've never seen direct evidence
of a glacier moving, so I was excited to see it for myself.
Yes, I rounded the
corner and saw two sticks on the ground and the third having fallen over.
I said on camera that it was about 6 cm. Actually, it was more like 5
cm, as the third stick had not fallen through yet. I got a bit excited
and exaggerated unintentionally. Not only did the ice melt 5 cm in length,
it melted about 3 cm downwards.
How
was I so sure there would be melt? Basically, the terminal face of this
glacier is below snowline. The ground is not cold enough to keep things
on it frozen, plus the sun is beating down from above. Thus, there is
melting everyday. Mike B, Kate and I documented that in the last two days
5 cm of ice have melted off the terminal face.
Kate then asked if
we now knew the glacier was retreating nope, we didn't until we
looked at where the glacier was in relation to a fixed point, in this
case, bedrock. If the glacier was moving downhill at a rate of 5 cm every
two days, then the measurement Mike B set up would be exactly as it was
two days prior. If the glacier was moving downhill faster than 5 cm every
two days, then the broomstick and nail would not have been straight. If,
as was the case, the glacial ice was melting faster than the glacier was
moving downhill, then it would appear that the glacier backed up it
actually just melted more than it moved forwards. (Glaciers, like rivers,
don't flow upstream.) Cool, cool result.
In
terms of the other team, it sounded like everyone had a fabulous time
up on the glacier overnight. Their measurements were really good as well.
It was fun to hear that a real glaciologist studying this glacier using
satellite images got results nearly identical to ours.
Back to top
|