Green World Trust

[Lucy Skywalker]

I finally found what I'd been searching - the piece on the discovery of tiny comets that bombard our atmosphere all the time, carrying enough water that over geological time this can account for the planet's oceans altogether. (Cometesimals do not, however, provide enough quantity to account for slowly rising sea levels despite temperature now falling. I wonder about sedimentation and estuarine outflow.)

The hypothesis was accepted until its scale was quantified, a scale which showed it to be challenging "sacred cow" paradigms such as the oceans' origin. Then the story tells how badly the author was treated; and though he knew this could happen he had no idea of the ferocity that would be unleashed.

It's a cracking story.

Out There http://smallcomets.physics.uiowa.edu/wp.html
The Original Discovery http://smallcomets.physics.uiowa.edu/blackspot.html

[Richard111]

This has indeed the WOW factor! A house sized lump of water! That is about 500 cubic meters of water using my house as a guide. And how many a year was it? About a million or so? Over several billion years this must add up!

BUT... how come? Where is this water, these "cometesimals", coming from? And why in such a steady stream? Aren't they visible in the atmosphere of Mars? Or Venus?

Questions, questions.. Hope we hear more of this.

[Mike Davis]

Lucy:
You have been right on both those items. The "Water" from outer space. and the erosion of land throughout history would add to the hieght of sea levels. Think about these also:
1. water is a molecule made up of hydrogen and oxygen H2O. Hydrogen and ogygen are volitile elements that are not stable but usually combine with other elements to create componds. Like CO2 for instance as carbon atom is a volitile element also. The only limit to the amount of water is the elements that make up water.

The mean sea level that is being discussed has very little acurate historical records. There is isostatic rebound from land being beneath ice that is still continueing since the last glacial maximum about 12 to 14 k years ago. This would also mean that the other end of that "plate" would be sinking. That would give us one sea level lower and one sea level higher. All the mountains are being washed to the sea!

The next question is what are we supposed to relate the current level to and how do we know if it is falling or raiseing. There is evidence to sugest that the level was higher 5,000 years ago and as much as 30 meters higher 100 k years ago. The Atlantic Ocean is getting larger and the Pacific is getting smaller due the plate drift. India is pushing under Asia. West of the Rockies North America is streaching apart. The west coast of California will become part of Alaska. The coral atolls in the pacific have been sinking for many years. The volcanoes build mountains and the mountains erode leaving the coral reefs that surrond the islands. then as the coral decomposes the land sinks.

Once upon a time the ocean people used the land to determine the sea level because they thought the land was stable. The land people used the sea level as a reference because they knew that the land was not stable. So if today you have land surveyed it will be shown as related to amount of elevation above sea level and sea level is determined by a tide guage that is attached to a point on land niether which is accurate. The satellite measurements are at best guesses.

I do not care about the guesses as one is as good as another as long as people are not trying to promote fear related to so mythical sea level!