[wxqc] Baraometer quality problems

[Philip Gladstone]

There is another factor in barometer adjustment. Some stations just 
add/subtract an offset to make the value come out right (but also have 
the elevation set wrong). This means that when the pressure changes, the 
reported pressure does not track correctly.

I suspect that there is a fair amount of this going on, but it is quite 
difficult to detect with any reliability. I have an experimental 
paramter that you can add to the site information page '?fit=1' that 
tries to calculate the best fit function to map the observations into 
the analysis value. If the multiplier is distinctly not =1, then this 
may be happening.

Philip

spamfree at pensom.org wrote:
> Hi,
> 
> Based on calculations I did a while back while writing some code to do barometer conversions  for Vantage Pro stations, I looked at the issue of station pressure vs. sensor pressure and the effect of a difference in elevation between the official station elevation and the elevation of the physical barometer sensor.
> 
> To make a long story short, unless the difference is greater than something like 50 or 100 feet, the difference is not consequential. You can account for the elevation difference by calibrating your barometer to a nearby reliable weather station.
> 
> Since the barometer values sent to CWOP are already adjusted for elevation, I don't think it's important if your physical barometer is 10 or 20 feet above or below your reported station elevation.
> 
> Best regards,
> Steve
>   
> 
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