[R] Classification of wind events

[Jim Lemon]

Hi Stefano,
Given only one observation point you will find it difficult. If your
automatic weather station is in the low area where the foehn wind is
felt, it can only be distinguished from a dry katabatic wind if the
upwind conditions are known. There is a similar but milder version of
this in eastern Australia, but it is usually of the latter sort. There
may be a way to measure turbulence above the peak of the high ground
with radar or something, but I'm not familiar with that.

Jim

On Tue, May 12, 2020 at 6:13 PM Stefano Sofia
<stefano.sofia using regione.marche.it> wrote:
>
> Dear R list users,
> I am aware that this question is not strictly related, at the present moment, to R code and it is more general. Please forgive me, but I need to share my thoughts with you.
>
> Foehn conditions on the southern slope of Alps happen with strong northerly flows that impact perpendicularly over the Apls. This situation triggers strong northerly leeward winds.
> Given a single automatic weather station, I would like to identify these periods starting from wind direction and wind intensity data. Frequency of data is quarter of hour.
> I would really find difficult to detect the moving windows of these events:
> - I can't analyse data day by day;
> - at the beginning and at the end of each event, when the process is not at full speed yet, the rotation is not always perfectly identifiable;
> - I cannot claim in principle that the direction of each consecutive observation is costantly and strictly from the chosen direction.
>
> Does anybody have a clue on how to start to build this process in the right way?
>
> Thank you for your attention and your help
> Stefano
>
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> Stefano Sofia PhD
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