How high could you pump steam?

[farmerben]

Suppose it was our goal to create artificial clouds to influence local rainfall and climate.   Conventional smokestacks and cooling towers often have vapor trails that dissipate well below cloud level.  If we inject steam at much higher altitude it will create more clouds.  

 

A giant nylon windsock would serve as a tube to convey the steam thousands of meters.  A toroidal hydrogen balloon at the top could help lift it.  Steam is a buoyant gas anyway so the horizontal vector is unstable.  It would bounce around like the vertical windsock signs seen at car dealerships, etc.  Such a device mounted to a powerful boiler could elevate steam above the clouds, even discharging steam in layers where the temperature is freezing and the humidity is zero.  

[mikegarrison]

Gas adiabatically rising in the air cools. Your steam would condense.

[farmerben]

43 minutes ago, mikegarrison said:

Gas adiabatically rising in the air cools. Your steam would condense.

I agree that condensation is the limiting factor, but it doesn't have to be adiabatic.  We can superheat and pressurize the steam at the source.

[HvP]

6 hours ago, farmerben said:

Suppose it was our goal to create artificial clouds to influence local rainfall and climate.

If you're worried about not having enough water from rainfall then where are you getting all this water to make the steam?

[mikegarrison]

1 hour ago, farmerben said:

I agree that condensation is the limiting factor, but it doesn't have to be adiabatic.  We can superheat and pressurize the steam at the source.

What does that have to do with it being adiabatic?

If you don't add heat during the rise, then it's adiabatic. If you want to counter the fact that it's going to cool as it  rises, you have to add more heat during the rising.

[farmerben]

1 hour ago, HvP said:

If you're worried about not having enough water from rainfall then where are you getting all this water to make the steam?

the sea

 

20 minutes ago, mikegarrison said:

What does that have to do with it being adiabatic?

If you don't add heat during the rise, then it's adiabatic. If you want to counter the fact that it's going to cool as it  rises, you have to add more heat during the rising.

New steam supplies pressure from the bottom adding energy continuously.  

[StrandedonEarth]

24 minutes ago, mikegarrison said:

What does that have to do with it being adiabatic?

If you don't add heat during the rise, then it's adiabatic. If you want to counter the fact that it's going to cool as it  rises, you have to add more heat during the rising.

I get what you’re saying, but what about having the steam at the base being at 500-600K (or hotter) and at 2-3atm of pressure, using the pressure to force the rise, and somewhat constrained by the “windsock” to reduce expansion cooling?

Start with enough heat to not have to add heat?

1 hour ago, HvP said:

If you're worried about not having enough water from rainfall then where are you getting all this water to make the steam?

Boil the oceans, of course!

As for the OP, water vapor is a greenhouse gas, balanced by the albedo of clouds.  Injecting vapor where the humidity is zero will not produce clouds until the relative humidity reaches 100 percent over a wide enough area, or it will disperse and all it will do is add to the greenhouse effect. So that means a LOT of water (and a LOT of energy) for the effect you’re seeking

[HvP]

12 minutes ago, farmerben said:

the sea

So you've built a desalination plant using the more energy intensive (and more expensive) distillation process, rather than just using the less energy intensive reverse osmosis technique and pumping or channeling the water to where you need it.

[mikegarrison]

39 minutes ago, StrandedonEarth said:

Start with enough heat to not have to add heat?

It will cool as it rises. Yes, if if it hot enough at the base, the cooling will not be enough to condense it for a while.

Saturated air cools at a rate of about 3degF per 1000 feet as it rises, up until it reaches the stratosphere. I'm not sure what super-saturated air would do.

So I guess it might only cool about 120degF on the way up to the tropopause, meaning hot enough steam might well reach all the way up to the stratosphere.

But that's just adiabatic cooling. Since the upper part of the troposphere is quite cold, the steam would also be losing heat through non-adiabatic processes as it heated up the surrounding air.

Anyway, yeah, if it's hot enough at the base, it will stay as steam a long ways. But that would have to be really quite hot steam.

Edited August 10, 2022 by mikegarrison

[mikegarrison]

48 minutes ago, StrandedonEarth said:

As for the OP, water vapor is a greenhouse gas, balanced by the albedo of clouds.

Clouds are quite complicated, as they tend to be cooling during the day under direct sunlight, but warming at night. I think there is more to it than just albedo, although that's part of it. I could ask the atmospheric scientist I work with, except he would probably give me a 45 minute explanation that I wouldn't be able to type up anyway.

[farmerben]

Steam in a pipe moves pretty fast, it might flow to the tropopause in a couple of minutes.   If we go above that, we can reach altitudes where water vapor does not exist, and our exhaust will become snowflakes.   Making steam at low altitudes in semi-saturated air probably increases the greenhouse effect more than albedo.  I think high altitude release does more to albedo.  

Desalinization on shore could be done in other ways.  This idea could work out at sea.   

[mikegarrison]

3 hours ago, farmerben said:

Steam in a pipe moves pretty fast, it might flow to the tropopause in a couple of minutes.   If we go above that, we can reach altitudes where water vapor does not exist, and our exhaust will become snowflakes.   Making steam at low altitudes in semi-saturated air probably increases the greenhouse effect more than albedo.  I think high altitude release does more to albedo.  

Desalinization on shore could be done in other ways.  This idea could work out at sea.   

LOL. You are not going to build a pipe that goes 40,000 feet straight up into the sky.

[kerbiloid]

Volcanic gases are water steam and carbon dioxide.

We need volcanoes.

The latter is very solvable in water.

We need underwater volcanoes.

The underwater volcanoes mostly belong to the mid-ocean ridges (because they are that exact place where they appear.)

We need to wake up the mid-ocean ridge underwateer volcanoes.
Then we don't need pipes and balloons.
https://en.wikipedia.org/wiki/Mid-ocean_ridge#Volcanism

Here we go.

Spoiler

[Hannu2]

Weather effects include so huge energies that it is impossible to produce by any known technology.  And if you think some unlimited scifi energy, it would be much more convenient to build  greenhouses or vertical farming systems than dump cubic kilometers of water to upper atmosphere and handle all nasty unexpected side effects.

[kerbiloid]

2 hours ago, Hannu2 said:

Weather effects include so huge energies that it is impossible to produce by any known technology. 

Blasphemy!

We warm the atmosphere, don't forget it.

[Hannu2]

7 minutes ago, kerbiloid said:

Blasphemy!

We warm the atmosphere, don't forget it.

We change composition of atmosphere and albedo of surface and if effects how much solar energy atmosphere capture. Straight effect of human energy production to air temperature is negligible.

[kerbiloid]

6 minutes ago, Hannu2 said:

We change composition of atmosphere and albedo of surface and if effects how much solar energy atmosphere capture. Straight effect of human energy production to air temperature is negligible.

Any human activity is based on the natural power redirection, and the composition changing is just an easy way to affect the balance and make the water evaporate.

[tomf]

2 hours ago, kerbiloid said:

Blasphemy!

We warm the atmosphere, don't forget it.

Well it has taken all human industrial capacity for the last 200 years to move the climate by a few degrees over the next 60 years so no one said climate change was easy.

[farmerben]

One function you could fulfill with this is to increase snowfall on Antarctica.   Ice loss has little to do with greenhouse warming at night in the winter, and much to do with how little precipitation falls on the continent.