Barometric sensor response difference between Air and Tempest

Note an ‘Air’ is the pressure device which is no longer available that paired with a ‘Sky’ in the earlier model weather station.
While I was analysing the pressure wave from the volcanic eruption I noticed that the wave recorded by my air is different to my Tempest. One reason would be that each reading is not taken at exactly the same time of the minute. Another reason is their locations are 4m apart in a slightly different location.
The graphs between High and low pressures are:


It makes me think that the air is more responsive.
cheers Ian :slight_smile:

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the 4 m difference shouldn’t matter. The wavelength is very long compared to your distance.

in Indigo color my tempest, blue is the air. Not much difference at all.
Note that in your picture the values are much different as well. The tempest has much lower values overall.

To see the wave accurately you need to zoom into the one minute values.
If you look at your wave at one minute resolutions you will most likely see a difference to the wave the same as I have shown with my two graphs. I found similar graphs around the World at nearby stations where I suspect that the Tempest graph does not record as high a peak and flattens out the 4 minutes in several places while the graphs from Airs had more wavy and pointy shape.
It makes a significant difference when you look at my one minute graphs and imagine only seeing every 5th point, it becomes very bland like your graphs display and the differences are dissolved.
The calibrations difference is irrelevant as I asked Weatherflow to stop calibrating to MSL because I do not want their calibration jumps influencing my measurements and calculations.
My point is only to compare how quickly and sensitively the different sensors respond.
I had been comparing waves within the main wave to notice the difference as it traveled in different places and air masses and directions. The wave shape and smaller waves within and following were different in different places but the Tempest graphs had flat spots where they probably were not flat spots because the Airs nearby did not have the flat spots.
This topic is regarding the sensitivity rather than the wave. I am using the wave as the means for comparison. Fortunately I believe the Canary islands has a few Air devices which produced very good graphs of the two waves colliding.
This is from The Canary islands after the main wave. Imagine it in 5 min resolution, all this detail would be missing. Unfortunately I did not capture a nearby Tempest for comparison because the Air gave a nice graph:

And because you are more familiar with the main wave it looked like this just after the smaller wave from the opposite direction joined it, but I would be better to explain that in the thread regarding the actual wave rather than this topic regarding the sensitivity.

cheers Ian :slight_smile:

sorry my mistake. I just downloaded the 1 minute data from the server (there it is available), imported it in excel and made this plot. The purple one is the tempest.

Sure enough the air seems a bit more responsive, or perhaps it is just less filtered.

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Yes it is weird almost like sometimes the Tempest is lazy for 3 minutes and just uses the same value until it decides to capture a new value? Because if it was an air blockage or a delay issue I would think the decimal point might at least change a little during the 4 minute flat spots.
And @sunny thank you for reminding me I can still get my own one minute history via the API :slight_smile: