Thread: Debunking hypothetical : 40 Days & Nights of Rain

Hope I'm okay in posting this here & hope this is in the right forum place (my apologies if not & feel free to move or delete etc.. mods) but purely as an excercise in hypothetical debunking, it occurred to me to ask the following questions : If it rained for exactly forty days and nights continuously :1. How deep would the resultant ocean be? 2. How much water would be required? Is there that much H20 on Earth? How dense would the clouds need to be to not be "rained out" much earlier?3. Would there really be enough to cover even Mt Everest (8850 m /29,000 ft)4. Assuming total cloud cover and constant rain how would that affect the Earth's albedo & thus temperature? (I'm guessing the necessary clouds would soon reflect the sunlight to the point where the Earth froze over entirely in a "snowball Earth" episode and the temperature dropped to a global average well below zero. Supplementary questions 4a. - assuming this happened how many days in would that point be & 4b. if the rain or now snow kept falling, would we reach a minimum temperature & what might that be?)& finally5. By way of comparison, is there any scientific, realistic example of global or near global rainfall, underwhat conditions could this occur and what is the longest & most extensive that a (water) rain / flood situation could feasibly be? Anyone care to do the maths here? (Ashamed to admit my own maths level is pretty lamentable. :-( ) Does anyone know if these calulations have been done & questions answered before and if so are they available on the web or in book somewhere? I'd presume & am pretty sure I'm not the first person to have thought of these questions.Again, no offence or anything is intended purely an excercise in "what-if" hypothetical "mythbusters-style" Great Flood myth debunking.

I'm quite sure I can't answer all of that, but I can answer part of the math part of it for you assuming certain things (because I don't have the info to make it dead accurate) But assuming that the earth is a perfect sphere (which we know it isn't) and that it doesn't absorb any of the water, using the diameter of the earth at the equator (which is slightly more than between the two poles) the volume of the earth is ~1,087,252,514,773 km cubed which I probably could have just found a more accurate number on the web but I did it the more difficult less accurate way, so excuse any 'slight' errors. For the water to cover Mt. Everest it would have had to rain ~2.3 billion (2,263,838,557) km cubed of water. That would be roughly 56.6 million km cubed of water per day. That would be 110,956,814 meters cubed of water for ever km squared of surface area of the earth per day. 4,623,200 m cubed/km squared per hour. Or to get just a little more picky, 77,053 m cubed/km squared per minute. That's just to touch the tip of it, I'm no scientist, but, I'm quite sure that even if all the polar caps melted (which would cause the water to expand) I still don't think there would be enough to do that. But that's the only part I can really help with. Hope that I gave enough info to help you out, or help someone else answer the rest of your questions.

I think that I made a possible mistake in the math toward the end, not sure, but, if someone wants to check my math I promise I won't be offended, it needs to be checked I'm quite sure, if not, I'll do it in a bit.

I'm not sure why you are typing kilometer cubed instead of cubic kilometer. It scales badly and they are frequently quite different units. Unlike most substances, water has maximum density at 4 degrees c. Ice takes up more room than the melt water. Ice floats on water while the frozen form of most everything else sinks to the bottom of that melted substance.
I'll guess Earth is short enough water to cover all of Colorado and similar elevations, by a factor of ten. There is a slight possibility, there is lots of available water 50 to 100 kilometers below the surface of Earth, but more likely that depth has been hot and dry, for the past 4 billion years. If Noah's flood really happened, it was a true miracle. Possibly it is a parable = fiction designed to teach a principle, enhanced by local floods.
It of course could sprinkle lightly and intermittently for 40 days and nights, over a large area. Neil

I don't have a calculator handy to confirm the calculations. We know that the continents used to be one, Pangea. This we know as sure as the nose on our face. Topography has probably fundamentally changed since Noahs day. Plate techtonics, due to the overwhelming new flood water pressure, could have caused the old continent to split up, reform and smash up into the mountain ranges we have today. They wouldn't have needed to build the tower of Babel if they had mountain peaks at their disposal. Another statement in the account of Noah is that the earth was watered by a mist prior to the rains/flooding. The assumption could be made that whatever the "mist" consisted of was actually a monumental volume of atmospheric water. Glad to hear someone else cares to get an answer to this. We can't know anymore, since we can't go back and record observable data.

Regardless of any of this, all you have to know is the rainfall per square inch. Look up the max rainfall measured pre square inch in an hour and then multiply that by 960 and you get a kind of bound on the depth.

I assume that you are talking about the story of Noah, so you might want to have a look at the actual biblica account instead of taking a phrase like "40 days and 40 nights" and running with it. The "out" in the story is that apparently, water welled up from the ground as well as falling from the sky....

Your question about albedo is interesting. I would imagine that with 100% cloud cover, about 50% of the light would be "absorbed" and a significant fraction of that would be converted into heat in the clouds. I'm not sure what net effect that would have on the temperature on the surface, since clouds are a pretty good thermal insulator.

If you solve the problem there are a bunch of climatologists and climate modellers that would like to talk to you!

Cheers.

Assuming a constant very high rain rate of 250 mm/hr, in 40 days(and nights) the total rain fall would be 240 meters. This would raise the sea level about 320 m because about 20% of the earth's surface would be above this new sea level. Where this water could come from is unknown and unknowable. If all the ice were to melt, all the atmospheric water were to precipitate, and all the ground water were to be released, the sea level would rise less than 30 m. The water in the atmosphere alone would raise the sea level less than 5 mm. Ice melting would be by far the major factor in sea level change.

Reference: Invitation to Oceanography by Paul Pinet. Website: jbpub/oceanography

Originally Posted by Growl

Assuming a constant very high rain rate of 250 mm/hr, in 40 days(and nights) the total rain fall would be 240 meters. This would raise the sea level about 320 m because about 20% of the earth's surface would be above this new sea level. Where this water could come from is unknown and unknowable. If all the ice were to melt, all the atmospheric water were to precipitate, and all the ground water were to be released, the sea level would rise less than 30 m. The water in the atmosphere alone would raise the sea level less than 5 mm. Ice melting would be by far the major factor in sea level change.

Reference: Invitation to Oceanography by Paul Pinet. Website: jbpub/oceanography

Yet this chart depicts sea levels as high as 320 m greater about 450 million years ago than they are today...

You know what I think? I think cosmic or other energetic rays crash into atmospheric water molecules (or oceans), splitting off H2 and O2, and the lighter hydrogen is subsequently blown off by solar wind. I think that's why oxygen levels in the Earth's crust are 47% (30.1% throughout the Earth) while hydrogen occupies only 0.14% of the Earth's composition, despite the fact that it's still the most abundance element throughout the universe!

I also think the Earth's oceans will continue to shrivel, until our land surface looks like that of Mars.

I will have to sidde with Neil on this particular point. I have no doubt that someone at one time experienced a massive flood, but perhaps when "the entire Earth" was covered in the story it could have been the Earth as it was known to the first person to tell/ or experience the story. It is possible for the Middle East (the most likley place for the story to have originated) to be covered in water, it being a low lying plain for the most part. Especialy if you take into account the possiblity of the ice caps melting a significant amount, which would come with a wrming trend , which would also increase evaporation and thus increase rain fall. So imagine yourself in a time that all the World known to you is a relativly small area of which you are familiar, and then a massive flood covers a great deal of it, to you, at least, the entire world is covered in water. Then also take into account a man lifes to see a great flood, possibly the scale of the flooding following Hurricane Katrina, for instance, then, as is the tradition of the time, this man tells this story to his grandchildren, whomin return tell the story to thier grandchildren, and so-on. In each generation's rendition of the story certain details are lost, or exaggerated, or down played, until eventualy after scores of generations, the story has little or no content from its original telling. So thats my theory of the origins of Noah's Flood, that or maybe it was a miracle, where a whole heap of water came and flooded the entire Earth. Just my Humble thoughts on the subject.

Originally Posted by mugaliens

Yet this chart depicts sea levels as high as 320 m greater about 450 million years ago than they are today...

You know what I think? I think cosmic or other energetic rays crash into atmospheric water molecules (or oceans), splitting off H2 and O2, and the lighter hydrogen is subsequently blown off by solar wind. I think that's why oxygen levels in the Earth's crust are 47% (30.1% throughout the Earth) while hydrogen occupies only 0.14% of the Earth's composition, despite the fact that it's still the most abundance element throughout the universe!

I also think the Earth's oceans will continue to shrivel, until our land surface looks like that of Mars.

I think you've got the shriveling part right on the money. Makes perfect sense to me. What I'm still trying to figure out,is the wobble of Earth, that takes place every twenty thousand years,like clockwork.What in the world put that into motion to start with. It causes the monsoons to move north and replenishes the Sahara Desert with at least three huge,fresh water lakes. This is according to what geologists have recently discovered and I'm absolutely intrigued...

What if Velakovsky was right, and no one believed it... ?