How do I make an accurate rain gauge?

[Dave]

Does anyone know how to make an accurate rain gauge? I first thought that a ruler in a container might do but this doesn't take into account the size of a container - surely a wide 4 litre container will give a different reading than a narrow 500ml container?

Does anyone now how to solve this problem??

[WhiteWolf]

Dave

As long as the top of the container has the same dimensions as the bottom, then the readings will be accurate. I've used a straight sided bucket and even an old fish tank.

Regards

WW

[KathyLauren]

As WhiteWolf said, the container for a simple rain gauge must be straight-sided, and the opening must be the same diameter as the body of the container. The volume of the container does not matter.

If you want more accuracy, you can use a funnel to increase the diameter of the opening, but you then must compensate when you take your readings. If, for example, the diameter of the top of the funnel is twice the diameter of the inside of the container, it will collect four times as much water, so you would divide your ruler measurements by four.

[Dave]

Thanks guys - I think I was trying to make things more complicated than they needed to be.