In very basic terms.... Earth had a covering, or canopy of water enveloping it. I can imagine Earth was very different in those days. Everything we know now of our climate, our fauna, our creatures..... our world.... was different than today. This canopy had many effects that can be ascertained by clues found not only in the Bible, but also in the historical records of many of the first civilizations. But let's start with the Bible first...
One of the most interesting stories in the Bible are the men who supposedly lived to unheard of ages.... the oldest of these men, Methuselah, lived 969 years. But there was a clearly defined cut-off point where men no longer lived to these ripe old ages, and it corresponds exactly when the canopy collapsed. So did the canopy provide a barrier of protection to the early man? Did it filter out harmful cosmic rays that currently degrade our life cycle to just under a mere century?
This one may not be from the Bible, but it is one of the clues we are seeking for proof. A planetary canopy is not something unheard of in our little solar system. Most of our planets have, or had them.... and some still have the "pre-canopy" ice rings. It would seem the planets closest to the sun have lost theirs before the others in the outer reaches. This process could be nothing more than planetary evolution of sorts and nothing controlled by "a God".... but could be understood by a God who would warn "his children" of it's coming. If I remember right a minor God hid behind a wall and told of the floods coming in the Sumerian story.... just as God warned Noah of it's coming.
That cut-off was what is known as the great flood of Noah.... (or also maybe Gilgamesh, but he's another story). Most scientists do not believe in the story.... mainly because it is Biblical..... too bad, their loss. The canopy, and the loss of it can explain quite a lot. Most theologians also have it all wrong. I find it amazing how they can take parts of the Bible and juggle the literal and the symbolic at their whim. Case in point.... they read the verse where it says the "fountains of the great deep broke up and flooded the earth", and literally think, and teach, that fountains of water sprang up from out of the ground and flooded the earth. Here's a news flash for them.... most all ancient civilizations referred to the sky, or heavens, as the "great deep".
According to the Bible, it had never truly rained prior to the flood, but there was dew. Most of us as "little scientists" have made a terrarium at one time or another. Taking our empty fish tanks and putting some plants and maybe a critter or two in it.... and covered with glass or plastic wrap. You would notice that it condensates, or dewed inside the aquarium. This would not have happened without your little "canopy" that you put on it. The dew we experience today is a mere fraction of the dew they had in the days of the canopy. When the canopy started to collapse in the from of rain in the tropical areas and in the form of snow or ice further to the north and south..... it frightened those early people completely.
With the canopy in place.... the "livable" areas of the Earth stretched farther north and south then one can imagine today. There are stories of Mammoths (or is it Mastodons) that have been found frozen with "daisies" still in their mouths and digestive tracts. Vegetation and animal life reached far into the upper and lower regions of the planet because of the terrarium like climate conditions created by the canopy. There are also stories worldwide of concentrated areas with compacted fossil remains of many different creatures... many of which would never intermingle when they were living. It would seem that they were washed away and into these "pockets" by a massive flow of water and mud.
We also have the story of Noah's rainbow. The people of that age had never seen a rainbow before the flood.... so when they observed one afterwards.... it was indeed a special event, one that had to signify the power of their God. Scientifically, we know a rainbow as we know today could not appear in a canopy environment.... but it can, and does, in a world without a canopy. I can imagine there must have been some form of prism like show of colors through the canopy.... but not like what we see today.

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