Topic: Barani MS Pro vs SmartCellino radiation shield comparison

[Jasper3012]

How is a WMO class 1 defined?

[hmderek]

How is a WMO class 1 defined?

Assuming this is current:

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[Jasper3012]

How is a WMO class 1 defined?

Assuming this is current:

https://wmoomm.sharepoint.com/:b:/r/sites/wmocpdb/eve_activityarea/Instruments%20and%20Methods%20of%20Observation%20Programme%20(IMOP)_67452102-7575-e911-a98e-000d3a44bd9c/Site%20Classification/CIMO_Guide_2014_en_I_1-2_Annex_1B.pdf?csf=1&web=1&e=R3y1pv

I don’t have access to that.

[Kallo78]

My position is not class 1
Maybe 2 but I don’t know. The nearest trees are at 40m and can make some shadows for a few minutes in winter mornings with low sun to the east 

[hmderek]

I don’t have access to that.

Modified the post to include it as attachment.

[Dvalente75]

@meteorology fan
I'd be curious to see a photo of your metro station with your shields

[mauro63]

I fear that the impact of buildings or structures takes on much greater importance than the height of the grass underneath
a class 1 in terms of grass underneath, with a house 10 meters away  will never be a class 1 but will automatically be a class 4 and not vice versa or, in better cases class 3 with an uncertainity over 1 degree

M.

[mauro63]

It is not the officially declared uncertainty that is important, it refers not to comparisons between different types of instruments but to the uncertainty of the air temperature parameter with respect to the presumed real value.
In our context it should be read as a scale of potential unwanted heat transfers, the higher the class, ergo of lower quality, the higher these unwanted heat transfers will be and will have a significant impact on the ability to correctly analyze differences in measurements so small

M.

[mauro63]

I see that my attempts are useless, good, let's wait for WMO to accept and make valid the MF classification instead of the official one

that's it for me

M.

[mauro63]

As for me, I will continue to post my data related to the SRS object of the post without further comments or answers that are not relevant

M.

[Jasper3012]

 That classification is so off lol. I’m apparently a class 4 because there is some lower vegetation nearby, when that probably has very little influence compared to a tree or houses. Nonsense in my eyes.

[mauro63]

That classification is so off lol. I’m apparently a class 4 because there is some lower vegetation nearby, when that probably has very little influence compared to a tree or houses. Nonsense in my eyes.

Are you referring to the WMO classification?

if so, keep in mind that it is the official one, and the GCOS and GSRN stations are based on this.

Obviously it must be interpreted and compliance with the individual indications is unequivocal, if you want a GSRN station things are even worse than described there.

A house, a building, a wall, or other similar structure has a notable impact both for reflected radiation and for convection, a plant or a tree have a much smaller impact but are very important regarding the roughness of the ground, which is able to strongly alter the natural ventilation in the layers close to the ground.

This is why future reference stations will require sidereal distances from any type of obstacle

M.

[mauro63]

Yesterday data


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M.

[tobyportugal]

At our level, the aim is not simply to have fun comparing where we live.
In any case, anyone who moves their equipment 100m will get different results.
When I see that some official stations are "weird", that some "amateur" stations called reference where there are large stones or surrounded by forests. I tell myself that a poorly set up station has nothing to be ashamed of.
I'm not casting stones at anyone, but it would be nice if we could get back to reality, because 99.99% of our sensors would be thrown in the bin to qualify for a class x or y.
To conclude, in my exchange with the guy from IPMA, when an installation is set up, a class is assigned. Apart from the aeronautical stations, few of them are sufficiently maintained or renovated to keep their classifications.

[Kallo78]

My report of yestarday

[Dvalente75]

I changed the filters....

[Meteorology fan]

Dvalente75 - Better not to have any on SHT35/45.

[Dvalente75]

On what basis?

[Jasper3012]

That classification is so off lol. I’m apparently a class 4 because there is some lower vegetation nearby, when that probably has very little influence compared to a tree or houses. Nonsense in my eyes.

 
In the case of green grass that's too high (>25 cm over a significant surface area, that's class 4), it doesn't make the mecha ventilated unit overheat more, because the more you cut the green grass (or the more humid it is if it's less green), the more the ventilated unit will pick up warmer convective bubbles due to the warmer ground (actually warmer air), it's not a bias that the ventilated displays more than the passive, it's the reality that the passive can't see), whereas a passive is penalized by this too-high green grass, because it reduces the natural ventilation speed by the greater roughness that reduces the wind speed at shelter height and in the shelter, the one naturally supposed to limit its radiative bias. The ventilated part doesn't need this wind. Grass that's too high (>25cm) would have to become totally carbonized, hyper-dry, and its surface T would have to be much higher than that of the air by being too close to the intake for it to penalize the ventilated mecha more than the passive (when dry, carbonized by the sun, it's verifiable by thermal camera, straw heats up enormously. We'll see greater instantaneous variations in the ventilated system than on very dry ground).

of course 

The grass surrounding the station isn’t particularly high (10 cm or so), it’s just that there’s some taller patches of grass nearby (see pic).

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[Jasper3012]

If models are correct, this evening should be clear and calm. Might be the first opportunity to see the low sun angle effect during this comparison. Curious to see whether there’s a different response between the shields.

[Jasper3012]

No clue, it’s @gvdb1111’s website, I just click download on the graphs here: https://meteo-be.net/nl/grafieken/male-brugge/last_24h

[Kallo78]

My Yesterday's report

[tobyportugal]

In the context of shelter comparison, for those who doubt the need to measure humidity in the shelter and not in another place:
https://humiditycalculator.vaisala.com/
Have fun playing with the temperature, height, humidity and you will see that what is actually in the shelter is very different than if we base ourselves on humidity from another point.
I could understand for comparisons in the Sahara or Greenland with a stable RH and almost identical vegetation between the points.
But we are far from this situation, especially in autumn.

[mauro63]

Mine yesterday data

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M.

[mauro63]

In the context of shelter comparison, for those who doubt the need to measure humidity in the shelter and not in another place:
https://humiditycalculator.vaisala.com/
Have fun playing with the temperature, height, humidity and you will see that what is actually in the shelter is very different than if we base ourselves on humidity from another point.
I could understand for comparisons in the Sahara or Greenland with a stable RH and almost identical vegetation between the points.
But we are far from this situation, especially in autumn.

Thanks for the link, I personally use the Rotronic one but I think they can be considered similar

https://www.processsensing.com/en-us/humidity-calculator/rotronic/

Regarding your observations regarding the importance of knowing exactly the absolute humidity inside an SRS, what type of instruments do you use for this type of measurement?

A native psychrometric sensor? one with a hydrogel bath? or have you organized yourself with a traditional psychrometer, and if so, how do you manage the problems related to the differences in dry bulb temperature compared to that measured in your screens?

Do you have any material relating to your tests to post and explain? It would be very interesting, I am about to purchase a psychrometer but I am still in the decision phase of which technology to use.

Sorry to all for OT

Thanks