Hi,
how would you tag an area that consists of snow or ice all year round? The areas in question are about 1-2 hectares in size, some are smaller. They can be easily recognised in summer aerial photographs and are quite common in the Alps. The areas do not have their own name. There is rock or gravel under the areas.
Some examples:
What is the landuse, natural or landcover value for this?
It is not a landuse its a landcover but the value snow or ice does not exist yet.
How about natural=snowfield (209 x)
Thanks for your answer!
What definition is used for a natural=glacier and would that apply here? If not, why not?
I believe that a permanent snowfield and a glacier are two different things. If I understand it correctly, in a glacier the snow has been compacted and transformed into ice.
How one can tell one from the other from an aerial image, I am not sure. But if it is small and shows no sign of flowing down hill, I would lean toward natural=snowfield.
As described in the wiki
Tag:natural=glacier - OpenStreetMap Wiki
and to my understanding this tag does not fit the minor remains of snow in your sample pics. I support natural=snowfield as proposed by @Langlaeufer.
Anyhow I would only tag it as such if the snow remains throughout the whole summer season, so you might have to climb up and take a proper measurement in September 
.
@n76 managed to squeeze in before I finished my extensive research on snow fields and glaziers … 
(a glacier) "… is continuously moving downhill "
From: Tag:natural=glacier - OpenStreetMap Wiki
To me, this is the key difference.
A glacier normally looks like this:
which is quite different form the small snow fields in the sample pics.
Thank you very much for your answers, that helps me understanding the differences.
I was wondering because on the following aerial photo the area on the bottom left is marked as a glacier, the area on the right is not.
Should both areas now be tagged as glaciers, as in my view they hardly differ at the moment. Or keep the left one as a glacier and tag the right one as a snowfield?
This is the identical zoom level. This small area near the water is also tag as a glacier. In the past they were all certainly mighty glaciers, but nowadays there is not much left.
I would not call any of these small snow/ice remains a glacier which is an object of a reasonable to huge size. The white patch in lower pic (same as first sample pic in your OP) could probably be the sad remains of a former glacier but I would not call it glacier any more.
Frankly spoken I would not tag these minor snow/ice patches at all because within a very short time they will be gone entirely. We all know that glaciers and snow caps all over the world disappear with increasing speed so I would understand these remains as seasonal stuff only. They could be gone even now, depending on the age of the imagery.
In the Scottish highlands, a snow patch occasionally survives the summer until the arrival of fresh snow. They tend to appear in the same places, some survive most years, or used to, and some of them have names (example). From what I can see, they have not been mapped, and no one has yet invented a tag for them. If you wanted to map them, you’d probably have to map them as nodes, because their extent will vary a lot depending on when the image was taken.
This is quite different from snow fields, which Wikipedia describes as permanent accumulations of snow and ice. This is an aerial view of the picture in the Wikipedia article:
And then there are the remains of actual glaciers, with names etc. that still tend to be mapped as natural=glacier as far as I know even if they are smaller every year. (At what point does a glacier stop being a glacier?)
I suppose it would take a bit of local knowledge and practice looking at aerial imagery to judge which of the three you’re looking at? I’d be keen to hear from others as I don’t have much experience mapping these things!
It stops being a glacier when there is no more mass-movement happening.
