Did Noah need oxygen above the mountains?
This question presupposes that Mount Everest was the height it is now, and that the air pressure would not have changed at that height above normal sea level with the addition of the flood water.
Mount Everest was not the height it is now during the Flood. Earth's highest mountains have fossils of sea creatures at their tops, showing they were once under the sea. The possibilities are that…
the sea rose to cover the mountains
or the mountains were once under the sea and have since risen out of the sea,
or a combination of the two.
Measurements suggest that Everest is currently rising at up to 15 centimeters (six inches) per year. If we extrapolate backwards, taking the rate of rise of 15 cm per year and the current height of Everest (8,848 meters, or 29,028 feet), Everest would have been at sea level only 59,000 years ago. If the current rate of rise is only the tail end of what has been happening in the past, the rise in the past could have been much greater, bringing the origin of Everest to the time of Noah's Flood.
Creationist scientists currently think that mountains such as the Himalayas were probably built by catastrophic movement of the Earth's continental plates during and after the Flood. The rate of rise now measured is just the remnant of the processes which occurred much faster in the past.
Mountain building occurred as a part of the geologic processes which deepened the oceans to take the waters off the land towards the end of the Flood. Some mountains could have existed before the Flood, but none like the current Himalayas, Alps, or Andes in height. In any case, there is only enough water on all the Earth to cover mountains about 3 kilometers (2 miles) high, if all the ocean basins were raised.
So, if the waters were not 9 kilometers deep, but much less, the question is no longer an issue.
Even if the flood waters were 9 kilometers deep, would Noah and company have had trouble breathing?
Absolutely not. Air pressure is caused by the weight of air above the point where the pressure is experienced. If the water was 9 kilometers deep, then the air that was in that 9 kilometers deep volume of what was atmosphere would have been pushed out and would then have sat above the water at 9 kilometers above the Earth's surface.
However, if we assume the worst case scenario of the radius of the Earth increasing by 9 kilometers due to the water, the surface area of the Earth plus water would have been greater than the Earth, so that the weight of air would have been spread over a bigger area so that the pressure would have been less.
How much would the air pressure have been reduced? Less than 0.3%. This is equivalent to standing on top of a 30 meter (100 feet) high building at sea level! There would also have been a negligible effect on the pressure due to changes in the force of gravity (which affects the weight of the air).
It is certain, therefore, that those on the Ark would have had no trouble breathing - without oxygen tanks.
Does the Bible claim that the Flood of Noah covered the entire Earth? Answer
Could Noah's Ark really hold all the animals preserved in the flood? Answer
Where did the flood water come from? Answer
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