Hypothesis 1: The pictures are FAKE.
I think this is a great hypothesis. Several people have said they look fake, and I myself first thought the images were from a spam e-mail. However, after asking around in Antarctica and doing some research on the internet I have found that the pictures are not fake at all, this actually occurred near Palmer Station on the Antarctic peninsula. So we must REJECT this hypothesis. The pictures are REAL.
Hypothesis 2: The pictures ARE of a wave that froze in mid-air.
This is a good starting point for hypotheses in this case. The pictures claim to be of a wave that froze in mid-air so this becomes our null hypothesis and must be taken into account. Lets look at the facts first. Ambient air temperatures can decrease to a level that boiling water will freeze when it hits the air. Even here in Antarctica I have seen hot water be thrown into the air where some of it evaporates on the spot and some of it freezes and hits the ground. So if that is possible (especially in the coldest part of winter when temperatures decrease far lower then they are currently) is this really a wave?
Think about what would have to be true. First there would have to be an open body of water that could splash up. In our research we drill holes into the lakes and sea ice and water does escape, but the holes freeze over so quickly that even while we are sampling we are forced to drill more holes because our instruments no longer fit throw the shrinking diameter of the hole. So the likelihood that such a wave could come from anywhere other then the ocean is small. Furthermore, the ice edge that borders the ocean near McMurdo can be hundreds of feet higher then the surrounding ocean, so waves could not get over the ice pack. In areas more near Palmer, where these photos were taken, the ice edge is not as staggering; however it remains true that if a wave froze instantly it would then drop to the ground, no longer supported by water's elastic and surface tension properties. At this point ice crystals would fall to the ground and be smashed. Finally, ice that freezes instantly is opaque in color (the glassy color comes from ice melting rather then ice forming) and has many more impurities than ice that is formed slowly has.
Hypothesis 3: Victoria (3rd grade) Hammond Elementary School: The structure was formed by glacier or Mountain water that melted creating a waterfall that refroze to form this wave-like formation.
This is a great hypothesis and it really uses a lot of different ideas that come into play in ice formation in Antarctica. The first important idea is that ice can melt, glacier ice does in deed melt and create waterfalls off the side of the glacier. Melting is also how glaciers move and glacial water replenishes the valley lakes that we work on every day.
So this is a great deduction. And as Victoria states, and I stated before, because of the type of ice that is shown (very glassy blue ice) it is possible to state that melting was in integral part of the ice wave, not as the e-mail suggests, freezing.
Hypothesis 3: They are formed by wind, similar to the great ventifact rock structures of the valley.
This is an interesting point. Several of the glaciers really are shaped by the wind the photo shown (right above) is of the Canada Glacier which is shaped by wind, just like rocks. The sides of some glaciers look like ripples on the water because the effect the wind has shaping the ice. This picture of the Seuss Glacier (right below) is one example of how the wind can make amazing patterns.
So this is a great hypothesis. And perhaps wind had something to do with the formation of these giant structures. But the fact still remains that the ice had to come from somewhere. It it is not water that was frozen and it is not compacted snow, or a glacier that was already in existence, then what in fact is it?
So what is REALLY happening?
The area of Antarctica where this photo was taken is the peninsula area. This is the most delicate ecosystem in Antarctica because it is north enough that the temperatures can change quite drastically.
Therefore, water flows during the majority of the Antarctic summer and icebergs like those portrayed in movies such as The Day After Tomorrow are formed rather regularly. Icebergs like these keep most of their mass below water. The water that surrounds the icebergs is warmer then the ice, so it makes sense that the ice will melt from the bottom up (which is the reverse of how ice freezes). When the underside of giant icebergs begins to melt the bergs can become very unstable.
A good experiment we can do to test this hypothesis is to find an ice cube and melt it in a glass of warm water. How does the ice melt? From the bottom or top? Does it start rocking around if you shake the glass slightly? Could you imagine that in a storm a big half melted iceberg could flip over?
That is exactly what we think happened in this case. The iceberg that was already melted on the bottom by the warmer water circling around it, became unstable, and in a storm it flipped over. The formation looks like it has been shaped by the wind or that it even was flowing water. But to the contrary the ice was melted due to the surrounding water!
Does it make sense? What do you think?
Thank you for your comments, especially Victoria of Mr. Hector's 3rd grade class. Keep reading and hypothesising and we can all come up with more answers to the really important questions!
1 comment:
Anna,
I received an e-mail with the Antarctic frozen wave pictures and I was truly amazed. Not only was I amazed by the pictures, at the same time I finally downloaded PowerPoint software and needed to become more familiar with designing PowerPoint presentations. Also, I am a substitute teacher in search of permanent work.
Well, I had the bright idea to use the wave pictures along with pictures of striped icebergs I had received through e-mail, (I would love to hear your scientific explanation for those too!) in a PowerPoint presentation. I had both a subject that students are required to learn and subject matter they thoroughly enjoy. Plus, (which was the original intent) I would become an effective utilizer of PowerPoint. At this point, I would say I have done thirty or more hours of research and design, and who knows if I'll ever get to use it (6th grade standard, and I need that permanent job to provide my own enhancements to the curriculum. Oh, and benefits and income for myself LOL!)
I have looked all over the web to find validation for the comments that accompanied the pictures (waves freezing in mid-air), or a scientific explanation for the ice formations and striped icebergs. I did find one page that said the formations were due to ice melting and not water freezing, but there was nothing to deem the page credible. Your page, however, was credible, and in addition geared toward education. Hot Dog! Finally, the jackpot.
I can't thank you enough for the opportunity to have someone like you to expand students and my horizons and knowledge.
Now, how do those icebergs get their stripes? You can google "Striped icebergs" and sites will appear in abundance.
Thanks Anna
Myra
Post a Comment