Manual TAB generation and Climate Analyst 2

[Donitz]

Hello.

I'm trying to create an R-script for generating TAB files from arrays of wind speeds and directions. I'm using The same data imported into Climate Analyst 2 and exported into TAB to validate the results.

I'm having issues getting the same result. While the sector frequencies match up perfectly, the wind distribution in the bins differ in most of them (but not all).

My question is, does climate analyst select the bin index with some other method than simply rounding up the wind speed to the next integer value?

[Duncan]

Hello,

We have a freely-available DLL which you could use for this: it's guaranteed to give the same results as WAsP tools. I will ask my colleague Matti to contact you.

As for the exact implementation of the binning method, I will ask the responsible scientist to post an explanation here.

Best wishes,

Duncan.

[Ole Rathmann]

Hi Donitz, in the creation of and OWC the algorithm also distributes "an event" between two adjecent bins according to the speed-discretization width, ws. So you should imagine that a certain speed measurement "U" in fact covers a range [U-0.5ws ..U+0.5ws], and the distribute the fractions of the event according to how much of this intervals falls in the two bins involved.

So, if practice this means that if U is just at the borde between two bins, then they will each get 0.5 count.

Same principle applies to direction, this time of course using the direction-discretization. Clear?

[Ole Rathmann]

Hi Donitz, since the OWC-generator in WACA works with a pre-defined number of speed-bins I cannot rule out that the last speed-bin is treated in a little bit special way.
Ole.