The Botany of Iceland - 01.12.1914, Blaðsíða 20

204
THORODDSEN
the eastern side the snow-line stands at a height of 400 metres
ahove sea-Ievel, on the western side at an altitude of 650 metres.
Upon the plateau itself, around the hase of Drangajökull, there are
numerous large, scattered wreaths of snow which taken collectively
would cover a Iarge area; they occur at an altitude of 250—500
metres. In the suminer of 1886—87 there occurred, in addition,
numerous wreatlis at a lower level — in sheltered places even close
to the sea-shore, especially at Snæfjallaströnd, where verv long snow-
drifts were lying on the terraces of the hasalt heds. In these districts
old banks of snow are usually very frequent at a height of 50—
100 metres above sea-level; the climate also is very raw and the
precipitation considerable; there are occasional snow-storms in the
middle of summer, and drift-ice with cold, damp fogs and drizzling
rain is a frequent visitor. The sea cuts into the land from all sides.
Above the snow-line proper there is naturally no vegetation,
with the exception of a few individuals which maintain their ex-
istence on projecting rocks and “Nunataks” in the ice. In the region
of permanent snow-drifts there occurs, only here and there, a poor
and very scattered rocky-flat vegetation, but in the zone of the
variable snow-drifts there may often be a vegetation of different
species which is rather luxuriant, considering all things. According
to my measurements in the years 1882—1898 the snow-limits were
about as follows (the snow-limits given in the table on p. 203 mav
serve for comparison): —
Snow-limit in metres Lowest limit of the permanent snow-drifts in metres Lowest limit of the variable snow-drifts in metres
Northern part of the north-western pen- insula 400-650 250-500 50-100
Snæfellsnes 800-1000 cir. 700 500-600
Odáðahraun 1400 1000 —
Mývatn — 700-800 —
Peninsula NE. of Eyjafjörður 1000 450-500 200
Austfirðir 900-1000 500-550 300-400
Plateau between Vatnajökull and Mýrdals- jökull 1100 600-700
Arnarvatnsheiði NE. of Langjökull 1000-1100 600-700 500-600
The neighbourhood of the southern lowland 1000-1100 800-900 —