What would temperatures on Venus be like if it had an earthlike atmosphere?

Question

Assuming an Earthlike atmosphere is possible. Would the polar regions dip below zero, even though Venus is closer to the Sun? Would there be places where the average temperatures are tolerable to humans?

Answer 1

because of its high temperature an earth-like atmosphere is impossible to form on Venus.

Answer 2

I think it's still probably hotter.. and it might be too hot for human to live there..

Answer 3

Let's say that we convert the atmosphere of Venus into an Earth-like atmosphere, complete with lower density, oxygen, nitrogen, etc.  Venus would still be hotter than Earth, though nothing like the blistering temperatures it has now.

Venus has no magnetic field.  But perhaps, if lots of water were introduced to the surface of Venus, some of that water could sink below the surface, and get the tectonic plate system lubricated enough to start back up.  That could create a magnetic field.  Then Venus would have a good chance of keeping it's new, friendlier atmosphere for a long time.

Where would we get that much water?  I dunno, maybe crash Ceres into it.  That would shake things up, and maybe give Venus a rotation like Earth's, and possibly even a Moon.

But back to the problem.  So we genetically engineer microbes that would eat sulphuric acid and carbon dioxide, perhaps dropping carbon and sulfur bricks to the ground, and leaving behind oxygen molecules.  We introduce nitrogen. Venus is still hot, but we could put a sun shade up at the Sun/Venus L1 spot.  And we could orbit various belts of orbiting satellites to provide shade, and at the same time collect solar power.  With careful control of greenhouse gases and shading, Venus could be made comfortable.

I'm not saying all this is easy.  Just possible.

Answer 4

If you have a Venus sized planet in a Venus-like orbit, but with an Earth-like rotation and an Earth-like atmosphere, then you would probably end up with scorching deserts at the equator, tropical jungles in the temperate regions, and temperate zones at the poles.

For humans, the best place I would imagine to be the high latitudes, but not the actual polar regions - because personally I don't fancy 6 months of even temperate darkness. Oh wait, Venus-like orbit, so 112 days of darkness... but still.

And if most of the planet was lush and tropical, just think of the insects in the warmer regions.... that thought would send me to the poles!

If you wanted to MAKE an Earth-like atmosphere on Venus, you'd have to find a way to remove most of the existing atmosphere, and induce a faster rotation somehow.... not easy to accomplish!

And you might want to trigger plate tectonics if you can!

Answer 5

As has already been stated - it is not possible for Venus to have an earth-like atmosphere.There are several reasons for this - not least is that Venus spins too slowly to have a magnetic field, so the atmosphere would be unprotected.

On Venus, the high density of the atmosphere means that it does have an ionosphere that protects it.

However, in the spirit  of the question - the temperature drop with distance from the sun as 1/sqrt(R).

So at 0.7 AU the temperature should be 1/sqrt(0.7) times higher. that makes the average temperature 20% higher or ~345 Kelvin (Earth's average temp is ~290K).

So I doubt there would be any regions that would drop well below freezing (I assume that's what you mean - the zero point depneds on whether you work in Kelvin. Celsius or Fahrenheit)

That said - the slow rotation means there should be significant differences between the day side and the night side! (see Mercury for example)

Answer 6

Well one thing that would help is if those dangerous gas clouds weren't so thick, it would ease up on the temperature a little bit.  

Because Venus is closer to the sun than earth, and that there's a greenhouse effect, the clouds trap in the heat which makes it way too hot to colonize a human civilization.  

It has been said that some creatures (not humans) can tolerate living in boiling water temperatures.  I don't know what these creatures are, but they could be below the Venusian surface crawling around and avoiding the extreme hot temperatures above the surface.