Jökull - 01.10.1998, Blaðsíða 52

-8000 -4000 0
specific balance (mm)
4000 -8000 -4000 0
specific balance (mm)
4000 -8000 -4000 0 4000
specific balance (mm)
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-8000 -4000 0 4000
specific balance (mm)
-1000 0
cumulative balance (106m3)
-1500 -500 500 1500
cumulative balance (106m3)
Fig. 12. Mass balance as a function of elevation 1994-1995;
bw and Bw: winter balance, bs and Bs: summer balance, bn
and Bn: annual net balance.
- Afkoma sem fall af hœð á nokkrum skriðjöklum, 1994- ^
1995; bw og Bw: vetrarafkoma, bs og Bs: sumarafkoma, b„ og m
B„: ársafkoma; (b sem metrar og B rúmmetrar vatns). ~t
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Runoff of water from the glaciers
The variations in the summer balance of the vari-
ous glaciers were reflected in the computed runoff to
the rivers corresponding to the summer balance
(Table 7). The runoff from Tungnaárjökull was simi-
lar to that of the year before, 353•10'1 m3 a ‘. In con-
trast, the northern outlets delivered more than two
times more meltwater than the year before to Jökulsá
á Fjöllum and Jökulsá á Brú. The glacial summer bal-
ance component in Jökulsá á Brú was similar to that
of Jökulsá á Fjöllum, 60% of the annual runoff. Dur-
ing the summer, the runoff from the glacier was high-
er than the river runoff (117%). Considerable portion
of the glacial melt percolates into the groundwater
storage and is discharged from springs downstream of
the streamflow gauges at Upptyppingar.
IV. THE MASS BALANCE 1994-1995
The mass balance was measured at 24 points on
four drainage basins (Table 8, Figs. 11 and 12), the
50
JÖKULL, No. 45, 1998