Genesis 1:6-8 :  

6 And God said: „Let there be an expanse in the midst of the waters, and let it separate the waters from the waters.“

7 And God made the expanse, and separated the waters which were below the expanse from the waters which were above the expanse. And it was so.

8  God called the expanse ‚heaven‘.

And there was evening and there was morning — the second day.

You can find the story of creation in chapter 1 of the first book of the Bible in the Old Testament. The book is called Genesis or First Book of Moses.

The hydrology of our earth was probably different in the beginning than it is today. It means that the appearance, circulation and distribution of water were different from what we know today. 

In Genesis, Chapter 2, you can find some

references about that. Nowadays, there are no longer large masses of water above the atmosphere as it was in the beginning.

The reason for that is the Great Flood. The Bible tells in Genesis chapter 6 to 8 about this Flood, that came upon the earth. Do you know why? It was because the wickedness of people was increasing more and more. (That’s a big separate topic to learn about!)

In the above mentioned chapters you can read about a lot of rain falling upon the earth and all the fountains of the great deep burst opening.

Scientists have determined that, given the current distribution of water, sustained worldwide rainfall— such as occurred during the Great Flood —would no longer be possible.