On 16/01/2021 10:08, N_Cook wrote:
All very pretty , such images as 10m wind speed on
https://www.ecmwf.int/en/forecasts/charts/catalogue
but next to useless without reference to the constant of proportionality
of pixel length to knots/kph/mph/mps or whatever of the wind arrows. Why
no conventional wind barbs , if they have to confuse it all with
temperature ?
Try googling gets nowhere as to an ECMWF explainer. Anyone been here
before and knows the constant of proportionality or do I have to compare
to GFS isotachs for say 19 Jan, the next locally high wind regime.? Is
it even a linear scale?


First interim datapoint ,as assuming GFS= ECMWF 3 days out, for 10m
average wind in the Biscay area of the N Atlantic plot.
60kph wind arrow = 33 pixels
So it could be a linear scale, as hurricane force wind would be
plottable on that scale.
Don't you just love super-computers.

--
Global sea level rise to 2100 from curve-fitted existing altimetry data
http://diverse.4mg.com/slr.htm