<p>Because of the recent <a href="https://edition.cnn.com/2024/05/29/weather/india-heat-record-water-rationing-intl/index.html" rel="nofollow noreferrer">intense heat wave in India</a>, I tried to think about possible mechanisms to mitigate such extreme heat waves. I had an idea that I'm pretty sure it's infeasible in any case, but it could be fun as a thought experiment.</p>
<p>It is well known that as the earth warms, the <a href="https://www.pnas.org/doi/10.1073/pnas.2319228121#sec-4" rel="nofollow noreferrer">lower</a> and <a href="https://www.pnas.org/doi/10.1073/pnas.2300758120" rel="nofollow noreferrer">upper</a> stratosphere cools, so in total the temperature difference increases. So, why don't we create a &quot;portal&quot; between the layers through the <a href="https://en.wikipedia.org/wiki/Tropopause" rel="nofollow noreferrer">tropopause</a>,) (using two airships at different heights and a connecting tube with fans) and use each layer as a reservoir for the other: cool air from the stratosphere to cool the troposphere, and damp air from the troposphere to seed clouds in the cooler stratosphere. It may be used to cool intense heatwaves, and generally work against the greenhouse effect.</p>
<p>Some possible issues I already thought about:</p>
<ul>
<li>The tropopause is a <a href="https://en.wikipedia.org/wiki/Cold_trap_(astronomy)" rel="nofollow noreferrer">cold trap</a>, so streaming damp air to the stratosphere makes us loose water into space, which is generally not good.</li>
<li>We may not gain anything if the intense heat is trapped at the lower levels, and the cold air will flow far from the original location of the portal.</li>
<li>It may simply be impossible to efficiently stream so much air between the layers.</li>
</ul>
<p>I'm a <a href="https://en.wikipedia.org/wiki/Merchants_of_Doubt" rel="nofollow noreferrer">physicist</a> not a climate scientist, and I fully admit that I didn't do all of the possible research regarding that idea (climate science is complicated). So don't treat this as a proper geoengineering suggestion, just an amusing idea to speculate about.</p>

CC BY-SA 4.0
2024-06-21T08:59:16.650Z
Read up on [potential temperature](https://en.wikipedia.org/wiki/Potential_temperature) to understand why this will never work (and why The Day After Tomorrow is unphysical).  Basically, the low-pressure stratospheric air will increase in pressure and thus heat up as it enters the troposphere.  And even if that weren't the case; the mass and thus thermal capacity of the stratosphere is much less than of the troposphere, so it couldn't be much of a heat sink in any case.
gerrit
CC BY-SA 4.0
2024-07-17T13:25:47.747Z
Came back here for something else, and noticed I never thanked you. So thanks! It really helped :)
Yoav Zack
<climate-change><temperature><geoengineering><troposphere><stratosphere>
Is it possible to cool the troposphere using the stratosphere?
Yoav Zack
# Is it possible to cool the troposphere using the stratosphere?

(Asked by: username_0 on 2024-06-20)

Because of the recent [intense heat wave in India](https://edition.cnn.com/2024/05/29/weather/india-heat-record-water-rationing-intl/index.html), I tried to think about possible mechanisms to mitigate such extreme heat waves. I had an idea that I'm pretty sure it's infeasible in any case, but it could be fun as a thought experiment.

It is well known that as the earth warms, the [lower](https://www.pnas.org/doi/10.1073/pnas.2319228121#sec-4) and [upper](https://www.pnas.org/doi/10.1073/pnas.2300758120) stratosphere cools, so in total the temperature difference increases. So, why don't we create a "portal" between the layers through the [tropopause](https://en.wikipedia.org/wiki/Tropopause),) (using two airships at different heights and a connecting tube with fans) and use each layer as a reservoir for the other: cool air from the stratosphere to cool the troposphere, and damp air from the troposphere to seed clouds in the cooler stratosphere. It may be used to cool intense heatwaves, and generally work against the greenhouse effect.

Some possible issues I already thought about:

* The tropopause is a [cold trap](https://en.wikipedia.org/wiki/Cold_trap_(astronomy)), so streaming damp air to the stratosphere makes us loose water into space, which is generally not good.
* We may not gain anything if the intense heat is trapped at the lower levels, and the cold air will flow far from the original location of the portal.
* It may simply be impossible to efficiently stream so much air between the layers.

I'm a [physicist](https://en.wikipedia.org/wiki/Merchants_of_Doubt) not a climate scientist, and I fully admit that I didn't do all of the possible research regarding that idea (climate science is complicated). So don't treat this as a proper geoengineering suggestion, just an amusing idea to speculate about.

**Tags:** climate-change, temperature, geoengineering, troposphere, stratosphere

> **Comments:**
> **username_1**: Read up on [potential temperature](https://en.wikipedia.org/wiki/Potential_temperature) to understand why this will never work (and why The Day After Tomorrow is unphysical).  Basically, the low-pressure stratospheric air will increase in pressure and thus heat up as it enters the troposphere.  And even if that weren't the case; the mass and thus thermal capacity of the stratosphere is much less than of the troposphere, so it couldn't be much of a heat sink in any case.  
> **username_0**: Came back here for something else, and noticed I never thanked you. So thanks! It really helped :)  

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## 0 answers

