[Weather] conversion help

[Matthew Smith]

Quoth Mark J at 11/21/2006 06:16 AM...

> Doubling the funnel area will halve the rain rate which the above
> suggests is acceptable. Steady rain versus downpours? I personally
> haven't logged any downpour greater than 6mm/hr within a 10 minute
> period, but that disguises very short bursts that could be very much
> higher...

13mm in ten minutes - and it bounces!  We're probably guaranteed at
least one fall like this per year.  It overwhelms our gutters and
downpipes so goodness knows what it would do to a gauge.  When I say
13mm, that's what my Lacrosse recorded, with its unmodified collection area.

Prolong a fall like that and the collector could well overflow as the
pressure from four or so inches of water would not be sufficient to get
it through the orifice fast enough.

> At the other end of the scale you could have <0.25mm rain with no tip,
> and that could dry up in the bucket and never be counted. Doubling the
> funnel area there will halve that amount.

We often have minor falls that don't register, but then I can only pick
up 0.7mm, although my new Hall-effect detector should, hopefully, double
that.

Whilst extending the collection area may be an obvious and easy hack, I
think what Mark is getting at is that we might really need to scale up
the whole design.

Cheers

M

-- 
Matthew Smith
IT Consultancy & Web Application Development
Business: http://www.kbc.net.au/
Personal: http://www.smiffysplace.com/
LinkedIn: http://www.linkedin.com/in/smiffy