Where is the Aerosol Density slider gone?

Before SU:7, it was a real handy tool to give the sim some further immersion for the polluted air effects, however I cannot find it any more in the whether tool window, there is a humidity slider instead now, that cannot practically replace it.

as the dev team currently seems to be looking into the weather issues after SU:7, i wish they would bring the aerosol slider back as well.


Yes, its a very STRANGE new control, named HUMIDITY, but with a scale range of 0 - 20

Humidity ?
Relative Humidity ?
Units ?
GIVR (Game Inverse visual range !! ) ?

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Yeah, looks like the humidity slider just replaced aerosol. It does pretty much the same thing in terms of reducing the visibility. Not sure if it controls any effects actually related to humidity like density or icing. It looks like they tweaked the color to be more gray than brown though.

it’s clear, however, technically aerosol and humidity are totally different things, the former is the measure of polluting particles in the air whereas the latter being the proportion of vaporized water molecules in the air.

just IRL, they can very easily coexist in the sim, imho. one is not a substitute to the other.

the funniest part is that the max humidity can be set at 20 %, what is it now, an earlier-than-usual global warming effect in the sim ?

Where is the Aerosol Density slider gone?

When last seen it was taxing into a fog bank. Witnesses report seeing this expression on the pilots face :grimacing:


You are assuming the units for “Humidity” are Percent, which would imply it was Relative Humidity.

Once again, with no Units specified in the UI, one is “assuming” way to much.

The relationship between Temperature, Dew Point Temperature & Relative Humidity, could easily be obtained from Tables in the sim.

If all 3 are to be depicted in a weather UI, then as one moves one of those 3, the others should change.

Then on top of the effects that the Humidity is creating, there is a different parameter, basically atmospheric pollution, that come into play with the humidity, in a far more complex way.

Bottom line: A slider named “Humidity” with a range from 0 to 20, just does not cut it.

One has to wonder how the MetroBlue data is interpreted to control such crude controls in the sim !!

Maybe this is the answer to why there is a reluctance to produce a Weather API, for obvious reasons of missing knowledge & implementation in the current system.

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it’s a convention to talk about humidity in terms of per cent. i’ve never seen a 0-20 scale that has an undefined unit. meteoblue is the specialist here i’m sure they do know what they are doing.

anyway my point is aerosol should come back separately as before and can well coexist with humidity with what ever scale they design it to have.

MeteoBlue may well be the weather specialists, but I do not think they designed the MSFS Weather control UI, and put HUMIDITY there !

btw, i thought the sim’s weather data provider is meteoblue.

You are of Course correct, so I edited my previous Typo - thank you

I must have METars on my mind :roll_eyes:

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The only humidity-related meteorological parameter that would make sense with that particular range of numbers would be mixing ratio - the ratio of the amount of moisture in a given parcel of air to the amount of dry air in the parcel, expressed in grams per kilogram.

However it is possible for the mixing ratio to be higher than 20 g/kg if the air temperature and dewpoint are equal (i.e. 100 percent relative humidity) and both are higher than 77 degrees F (at sea level ISA conditions) At absolute pressures below 29.92 in/hg the mixing ratio number will be even higher than 20 for warm saturated air, so I’m not sure if the new “humidity” slider represents mixing ratio. It would be an unusual parameter to use in a consumer flight sim to represent “humidity”, although it would make perfect sense to a meterologist.

That’s interesting. You’d expect the temp slider to have some affect on the visibility too then wouldn’t you? But it and pressure don’t. Only humidity affects visibility. And the max “humidity” value is nowhere near that of dense fog/cloud like if the air were saturated, regardless of the temp. I’ve noticed the humidity visibility affect is actually a different color than the Live Weather mist/haze. It’s a little more brown, and the Live Weather effect is grey. I’m guessing they just retasked the aerosol density feature to do whatever this humidity is. Probably mainly a visual effect, rather than a meteorological one.

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that’s why it was a bad decision to replace aerosol thing that just works for a visual effect with humidity that is totally a different thing.

The proper visibility control for a flight simulator would be one that adjusts visibility in standard aviation units of statute miles/yards or kilometers/meters.


Even FSX had that years ago.

They can clearly do it since Live Weather is doing it: setting visibility to a specific distance. It’s kind of a mystery what their intent is with the weather settings menu though. Maybe it was just “pencils down, time’s up, turn in what you’ve got” when the SU7 deadline hit, and they’re literally in the middle of changing this. Their reasoning for not doing what FSX did was that FSX used a really primitive graphics trick like z-depth fog, which doesn’t work with Flight Simulator’s next gen volumetric weather engine. And that’s cool, but if their goal is a proper next gen flight sim instead of using simple hacks, why are they checking in code that isn’t ready for prime time?

We’ve talked about this to death for months, but ideally they would have particulate aerosol density, relative humidity, and prevailing visibility distance sliders, where the aerosol and RH would be locked to visibility and vice versa. Ideally on controllable layers too.


I laughed big time, thanx mate. seriously big time.

usual developer mode, last minute call actions.


All particles in the atmosphere are considered aerosols, not only solid particles, also moisture is considered an aerosol.

“An aerosol is a suspension of fine solid particles or liquid droplets in air or another gas. Aerosols can be natural or anthropogenic. Examples of natural aerosols are fog or mist, dust, forest exudates, and geyser steam.”

There could be two sliders, one for solid particle and one for relative humidity. Solid particles in the air together with the humidity level influences the visibility.

If there are more solid particles in the air, there are more “condensation nuclei” for water to condensate on. Relative humidity can be close to 100% without any mist or fog due to lack of condensation nuclei, so one influences the other.

Personally I’m not interested at all what is going on in the background. I want precise control over visibility / RVR in meters, what relative humidity, dewpoint or aerosol density it uses in the background to accomplish this is irrelevant to me.

II simply don’t think so, go to windy.com and see that they have different concentration maps for aerosol and humidity under separate headlines.

Yeah could be, not the correct definition of what an aerosol is though.