Jökull - 01.01.2019, Blaðsíða 112

Remote sensing of snow patches on Tröllaskagi Peninsula, N-Iceland
Figure 3. Intersection of PSPs of different years in Kerling: (a) Landsat-5 data from period 1 (six images), (b)
Landsat-7 data from period 2 (four images), (c) Landsat-8 and Sentinel-2 data from period 3 (four images), (d)
all years until 2016 (15 images) and (e) intersection of all PSPs until 2017 (16 images). The hillshade is derived
from the DEM (25 m resolution) provided by LMI. – Fannir sem sjást á öllum gervitunglamyndum á ákveðnum
tímabilum í Kerlingu.
The snow patch distribution for different elevation
bands and time periods was calculated for each study
area. In Almenningar and Úlfsdalir most of the snow
patches are below 800 m a.s.l., in Brimnesdalur more
than 50% of the PSPs occur above 800 m a.s.l. for all
time periods. In Kerling and Búrfellsdalur the major-
ity of the snow patches occur above 800 m a.s.l. and
also in the Sakka area many snow patches are located
above 800 m a.s.l. (Appendix - Figure A1).
Based on the PSPs mapping the likelihood of
snow patches to occur in each study area was explored
(Figure 4). In Almenningar and Úlfsdalir (Figure 4a)
the likelihood of PSPs to occur is much smaller than,
for example, in Brimnesdalur. However, snow patches
with a very likelihood are mapped below channels on
the south side of Almenningar as well as on the north
facing slopes in Úlfsdalir. In Brimnesdalur (Figure
4b) a distinct pattern of snow patch likelihood of oc-
currence is observable. There is very high probabil-
ity that snow patches occur just below the mountain
summits on the eastern side of the valley, much lower
probabilities at lower elevations on the eastern side of
the valley and almost no probability for snow patches
on the west side of the valley. Notably, the mountains
on the east side of the valley reach 1000–1100 m a.s.l.
and are 300–400 m higher than on the west side. In
the Kerling (Figure 4c) area the snow patches around
the rock glacier have a high likelihood of occurrence
JÖKULL No. 69, 2019 111