Would the water remain in lquid form?

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willstaruss22
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Lets say Earths atmospheric pressure was reduced to 0.10 bar which is 10% Earths atmospheric pressure. The boiling point at this pressure is 113 degrees F. Due to the atmosphere being thinner there is a greater temperature difference with higher highs and lower lows in a 24 hour period.
Lets say in a large area over the pacific ocean the air temperature in the day time reaches 130 degrees F and the temperature in the night time reaches 60 degrees F. This temperature difference is over a 24 hour period over a body of water. Would the oceans reach boiling point given the atmosphere is reaching above the boiling point for the given atmospheric pressure or will it remain a constant liquid because of the lower temperature?
 
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willstaruss22 said:
Lets say Earths atmospheric pressure was reduced to 0.10 bar which is 10% Earths atmospheric pressure. The boiling point at this pressure is 113 degrees F. Due to the atmosphere being thinner there is a greater temperature difference with higher highs and lower lows in a 24 hour period.
Lets say in a large area over the pacific ocean the air temperature in the day time reaches 130 degrees F and the temperature in the night time reaches 60 degrees F. This temperature difference is over a 24 hour period over a body of water. Would the oceans reach boiling point given the atmosphere is reaching above the boiling point for the given atmospheric pressure or will it remain a constant liquid because of the lower temperature?

You can't get such a large temperature difference above the ocean. At daytime the sun will shine into the water, and it will have to heat a layer some tens of meters thick. Evaporation will limit the temperature rise also. Even with the sun directly overhead and all energy going into evaporation., you can only evaporate 1.6 mm/hour. ( 1kw/m^2 sunshine and 2.26 MJ/kg to evaporate water)

rapid cooling at night over a warm ocean will surely produce clouds or fog.
 
Even with an atmosphere 10% as thick as Earths the temperature difference won't be as big? I always thought that there would be bigger highs and lows with a thinner atmosphere.
 
willstaruss22 said:
Even with an atmosphere 10% as thick as Earths the temperature difference won't be as big? I always thought that there would be bigger highs and lows with a thinner atmosphere.

But to get the air above the ocean to heat up, you've got to heat up the ocean first, and the heat capacity of the ocean hasn't changed.
 
willem2 said:
Even with the sun directly overhead and all energy going into evaporation., you can only evaporate 1.6 mm/hour. ( 1kw/m^2 sunshine and 2.26 MJ/kg to evaporate water)
.

Would a change in atmospheric pressure change the latent heat of vaporization of the water?
 
So basically the ocean would remain liquid even with an atmosphere this thin? Interesting and i also forgot that there is a lot of water to heat up.