<p>In <a href="https://arxiv.org/pdf/2012.02247.pdf" rel="nofollow noreferrer">Corlies et al. (2020)</a>, which analyses instrumentational requirements for a possible future Titan orbiter mission, a modelled transmission function for Titans atmosphere as function of wavelength and chemical species is shown in their Fig. 1 (Can plots from papers on the arXiv legally be used here?).</p>
<p>That figure clarifies that Titan's tholin hazes possess significant absorption opacities in the optical, overlapping with Rayleigh and Mie-scattering, but stronger in effect. This effect is weakening strongly the deeper into the infrared one progresses, with a small high-absorption bump at 3 <span class="math-container">$\rm\mu m$</span>. The weak have continuum opacity however reaches deep into the near-infrared, trapping very minute amounts of the planets emitted infrared heat. The latter process is however dominated by methane.</p>
<p>Additionally, <a href="https://ui.adsabs.harvard.edu/abs/2016Icar..270..355D/abstract" rel="nofollow noreferrer">Doose et al. (2016)</a> had a look at the single scattering albedo <span class="math-container">$\omega_0$</span> of Hazes, which gives rise to reflection of incident sunlight. In the entire atmosphere this quantity is very high, <span class="math-container">$\omega_0&gt;0.9$</span> at <span class="math-container">$750$</span> nm, but with a complex behaviour, dropping to smaller values above 0.9 at <span class="math-container">$500$</span> nm.</p>
<p>Together with the previous answer in this thread, I synthesize the following picture for the role of Titan's hazes onto its atmospheric energetics:<br />
1.) Hazes readily absorb UV radiation, making it available for atmospheric photochemistry. Photochemical products rain out downwards into the troposphere, but barely contribute to further energetic activity.<br />
2.) In the optical hazes scatter and absorb both strongly. Both factors lead to a blockage of sunlight towards the surface and hence the conclusion must be that Titan's hazes force an anti-greenhouse effect in the stratosphere.<br />
3.) In the infrared, Hazes are unimportant for the energy balance. Here Methane keeps the planet warm-ish with a mini-greenhouse effect using the remainder of sunlight left by the hazes.</p>

CC BY-SA 4.0
2020-12-07T16:19:16.153Z
2020-12-07T16:19:16.153Z
AtmosphericPrisonEscape
<p>So, I've googled and wiki'd on this, but no clue, so I turn my question to the community:</p>

<p>Given Titan's nice orange haze that is supposedly composed of <a href="http://en.wikipedia.org/wiki/Tholin" rel="noreferrer">Tholins</a> and strangely coincides with its stratosphere (taken from wikipedia)</p>

<p><img src="https://i.sstatic.net/TBjvv.png" alt="enter image description here"></p>

<p>I got to think whether the haze takes the role of clouds on earth when it comes to energetics. From this a bunch of questions arose:</p>

<ul>
<li>Do we know whether the haze is responsible for heat trapping and thus, the formation of a stratosphere on Titan?</li>
<li>What about radiation transport modelling with those particles, is this successful?</li>
<li>Also I'd be interested in what we know about the stability of Tholins. Could they survive harsh irradiation that atmospheres on Hot Jupiters do encounter?</li>
</ul>

<p>I would like to be able to make a statement such as "Dust" or "Haze-controlled" energetics for the stratosphere of Titan, if this is so. It would be nice if you helped to clear this up.</p>

CC BY-SA 3.0
2014-12-11T22:36:36.017Z
Sorry Mods? Who deleted @Sabre Tooth 's answer and why?
AtmosphericPrisonEscape
CC BY-SA 3.0
2014-12-12T00:21:50.287Z
Ah okay. Well, it was part of the puzzle so I for sure didn't consider it useless in any way. It's nowhere written that one single answer must contain all we know about the question, and I hope stackexchange never will be this uselessly strict. Also you apparently did some work for that, so I was just about to upvote when it got deleted.
AtmosphericPrisonEscape
CC BY-SA 3.0
2014-12-12T00:24:58.380Z
I would consider it useful.
AtmosphericPrisonEscape
<solar-system><planetary-atmosphere><atmospheric-effects><titan>
Energetics of Titans Tholin haze
AtmosphericPrisonEscape
# Energetics of Titans Tholin haze

(Asked by: username_0 on 2014-10-30)

So, I've googled and wiki'd on this, but no clue, so I turn my question to the community:

Given Titan's nice orange haze that is supposedly composed of [Tholins](http://en.wikipedia.org/wiki/Tholin) and strangely coincides with its stratosphere (taken from wikipedia)

![enter image description here](https://i.sstatic.net/TBjvv.png)

I got to think whether the haze takes the role of clouds on earth when it comes to energetics. From this a bunch of questions arose:

* Do we know whether the haze is responsible for heat trapping and thus, the formation of a stratosphere on Titan?
* What about radiation transport modelling with those particles, is this successful?
* Also I'd be interested in what we know about the stability of Tholins. Could they survive harsh irradiation that atmospheres on Hot Jupiters do encounter?

I would like to be able to make a statement such as "Dust" or "Haze-controlled" energetics for the stratosphere of Titan, if this is so. It would be nice if you helped to clear this up.

**Tags:** solar-system, planetary-atmosphere, atmospheric-effects, titan

> **Comments:**
> **username_0**: Sorry Mods? Who deleted @Sabre Tooth 's answer and why?  
> **username_0**: Ah okay. Well, it was part of the puzzle so I for sure didn't consider it useless in any way. It's nowhere written that one single answer must contain all we know about the question, and I hope stackexchange never will be this uselessly strict. Also you apparently did some work for that, so I was just about to upvote when it got deleted.  
> **username_0**: I would consider it useful.  

---

## 1 answers

### Answer by username_0 on 2020-12-07. Score: 1

In [Corlies et al. (2020)](https://arxiv.org/pdf/2012.02247.pdf), which analyses instrumentational requirements for a possible future Titan orbiter mission, a modelled transmission function for Titans atmosphere as function of wavelength and chemical species is shown in their Fig. 1 (Can plots from papers on the arXiv legally be used here?).

That figure clarifies that Titan's tholin hazes possess significant absorption opacities in the optical, overlapping with Rayleigh and Mie-scattering, but stronger in effect. This effect is weakening strongly the deeper into the infrared one progresses, with a small high-absorption bump at 3 $\rm\mu m$. The weak have continuum opacity however reaches deep into the near-infrared, trapping very minute amounts of the planets emitted infrared heat. The latter process is however dominated by methane.

Additionally, [Doose et al. (2016)](https://ui.adsabs.harvard.edu/abs/2016Icar..270..355D/abstract) had a look at the single scattering albedo $\omega\_0$ of Hazes, which gives rise to reflection of incident sunlight. In the entire atmosphere this quantity is very high, $\omega\_0>0.9$ at $750$ nm, but with a complex behaviour, dropping to smaller values above 0.9 at $500$ nm.

Together with the previous answer in this thread, I synthesize the following picture for the role of Titan's hazes onto its atmospheric energetics:  
1.) Hazes readily absorb UV radiation, making it available for atmospheric photochemistry. Photochemical products rain out downwards into the troposphere, but barely contribute to further energetic activity.  
2.) In the optical hazes scatter and absorb both strongly. Both factors lead to a blockage of sunlight towards the surface and hence the conclusion must be that Titan's hazes force an anti-greenhouse effect in the stratosphere.  
3.) In the infrared, Hazes are unimportant for the energy balance. Here Methane keeps the planet warm-ish with a mini-greenhouse effect using the remainder of sunlight left by the hazes.


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