While watching the film based on the incident, if you have ever wondered how it would have been to live the life of Jack and Rose, you can now visit the wreckage left behind with your own eyes. It was only in 1985, 35 years later, that its remains were discovered. How much it tilts or rolls depends on the shape of the berg, sea conditions, atmospheric conditions, rate of melting, etc.It was in 1912 that the "unsinkable ship" Titanic collided with an iceberg in North Atlantic and sank along with several people beneath the waves. Of course icebergs aren’t designed toys that will perform predictably. Then it reaches the critical point and tips over all at once. As the water makes its way to the head, the bird tips slowly at first. You know those ‘drinking bird’ toys? The bird is upright as long as most of the liquid is in the bottom bowl. This doesn’t mean that it will roll exactly 180º it will roll until it finds its new balance. At some point the top may become heavier than the bottom and the iceberg will roll. As this happens the iceberg will begin to tilt so that it is in equilibrium with its new CG. So as the submerged part of the iceberg melts the CG changes. That is, it’s no longer part of the iceberg. The meltwater does not remain ‘attached’ to the iceberg, but mixes with the surrounding ocean. Only the submerged portion is melting at a faster rate than the portion that is in the air. So you’ve go this iceberg that’s floating happily along. Change the CG, and the attitude will change. It will float in the water in whatever attitude is determined by the CG. The boat wil list to starboard since the CG has changed. Now you decide to sit on the starboard gunnel. You’re sitting right in the middle of it. The boat will roll over.īut wouldn’t this presume that the berg was somehow ‘balanced’ on the water? As Walloon mentioned why wouldn’t it gradually float lower as the bottom melted? I’m not suggesting they don’t turtle, just that might be another factor at work. But imagine a heavy man climbing to the top of the mast of a small sailboat (analogous to the submerged portion of the berg melting more quickly than the top). ![]() As an analogy, this is like the top of an iceberg melting more quickly than the submerged part. Think of a rowboat that springs a leak on the bottom. To simply sink down in the water without turning over the melting rates would have to be equal, or the top would have to melt more quickly than the bottom. Or, as noted in the links, it may break up and the individual pieces will find their own buoyancy balances. When enough of the submerged portion melts, the top becomes heavier than the bottom and the berg rolls. So the submerged portion of the berg melts more quickly than the non-submerged portion. The water may be 1☌ – and water conducts heat better than air – and it may still be freezing topside. As a berg drifts northward (from Antarctica) or southward (from the Arctic), the water gets warmer. It was not infrequent that the water temperature was warmer than the air temperature. ![]() ![]() When I lived in SoCal I’d hear the surf report every morning. Water is much more massive than air, and retains heat better. To reiterate what Musicat posted, they become top-heavy because of different melting rates of the ice in water and air. Why is it that they don’t sink down as Walloon proposed? The bergs melt, become unstable and roll over repeatedly, eventually becoming almost invisible, treacherous “bergy bits”, until finally they disappear altogether.įascinating. In fact, what you’re looking at could once have been the iceberg’s bottom. You can see here from old waterlines that this one has rolled slightly. They melt unevenly, and roll over without warning. Then when the iceberg becomes top-heavy and unstable, it turns over in a matter of seconds…Īlthough they can be massive, icebergs are not stable. This rotation can take place gradually, up to a point. The amazing shapes that irregular and rounded icebergs often acquire is the result of melting under water, so that when the icebergs roll upside down the sculptured forms become visible. While melting does not play a big role in the disintegration of the larger icebergs, it is the main reason why small icebergs eventually disappear. Icebergs that drift northwards melt quickly in the warmer seas, but close to the Antarctic coast where the sea-water temperature measures only +1☌, they can last for years. It would continue to sink down as it melted so that only 1/8 was above the water. my point being that an iceberg could never get “top heavy”.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |