Jökull - 01.01.2013, Side 84

P. Crochet
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m
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50
15
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25
0
Cold
Wam
71−00 ●
p<0.05
p<0.1
p>=0.1
SWE for VHM−10
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m
/d
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0
50
15
0
25
0
Wet
Dry
71−00 ●
p<0.05
p<0.1
p>=0.1
SWE for VHM−10
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m
m
/d
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0
1
2
3
4
5
Cold
Wam
71−00 ●
p<0.05
p<0.1
p>=0.1
Snowmelt for VHM−10
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m
m
/d
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●0
1
2
3
4
5
Wet
Dry
71−00 ●
p<0.05
p<0.1
p>=0.1
Snowmelt for VHM−10
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m
m
/d
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0.
0
1.
0
2.
0
3.
0
Cold
Wam
71−00 ●
p<0.05
p<0.1
p>=0.1
Rain for VHM−10
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m
m
/d
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0.
0
1.
0
2.
0
3.
0
Wet
Dry
71−00 ●
p<0.05
p<0.1
p>=0.1
Rain for VHM−10
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m
³/
s
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S O N D J F M A M J J A
5
10
15
20
25 Cold
Wam
71−00 ●
p<0.05
p<0.1
p>=0.1
Streamflow for VHM−10
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m
³/
s
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S O N D J F M A M J J A
5
10
15
20
25 Wet
Dry
71−00 ●
p<0.05
p<0.1
p>=0.1
Streamflow for VHM−10
Figure 5. Median monthly snowpack, snowmelt, rain and streamflow at gauging station VHM-10 in cold, warm,
wet and dry years and in the 1971–2000 period. Comparison between warm and cold years (left) and between
wet and dry years (right). Months with significant differences between subsets are shown with a triangle (10%
level) and a square (5% level). A dot (•) denotes insignificant changes. – Miðgildi mánaðarmeðaltals upp-
safnaðs snjós, snjóbráðnunar, regns og rennslis fyrir vatnshæðarmælinn VHM-10 fyrir köld, hlý, vot, og þurr
ár, og fyrir tímabilið 1971–2000. Samanburður á milli hlýrra og kaldra ára t.v. og á milli votra og þurra ára
t.h. Marktækar breytingar eru merktar með þríhyrningi (10% markið) og ferningi (5% markið). Ómarktækur
mismunur er sýndur með •.
with dry years, in some months in winter and/or
spring, at a number of catchments located both in the
north and the south. A significant increase was also
found in wet years during the summer period, espe-
cially in August, except for the southern catchment
VHM-64 where there was no difference in that season.
Few significant changes were observed in autumn be-
tween wet and dry years.
Streamflow
Warm years often generated larger monthly stream-
flows than cold years in winter and spring, for river
basins with increased meltwater production and/or
greater amounts of precipitation falling as rain. For
non-glacierized catchments, a temperature increase
advanced the onset of spring snowmelt, therefore
spring discharge was larger in warm years than in cold
84 JÖKULL No. 63, 2013