Abstract
We have used Radar Altimeter 2 (RA‐2) onboard ESA’s EnviSAT and Geosciences
Laser Altimeter System (GLAS) onboard NASA’s ICESat to map the elevation change of
the Flade Isblink Ice Cap (FIIC) in northern Greenland. Based on RA‐2 data we show that
the mean surface elevation change of the FIIC has been near zero (0.03 ± 0.03 m/a)
between fall 2002 and fall 2009. We present the elevation change rate maps and assess the
elevation change rates of areas above the late summer snow line (0.09 ± 0.04 m/a) and below
it (−0.16 ± 0.05 m/a). The GLAS elevation change rate maps show that some outlet glaciers,
previously reported to have been in a surge state, are thickening rapidly. Using the RA‐2
measured average elevation change rates for different parts of the ice cap we present a mass
change rate estimate of 0.0 ± 0.5 Gt/a for the FIIC. We compare the annual elevation changes
with surface mass balance (SMB) estimates from a regional atmospheric climate model
RACMO2. We find a strong correlation between the two (R = 0.94 and P <0.002),
suggesting that the surface elevation changes of the FIIC are mainly driven by net SMB. The
correlation of modeled net SMB and measured elevation change is strong in the
southern areas of the FIIC (R = 0.97 and P <0.0005), but insignificant in the northern
areas (R = 0.38 and P = 0.40). This is likely due to higher variability of glacier flow in the
north relative to the south.
Original language | English |
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Pages (from-to) | F03024/1-F03024/9 |
Number of pages | 9 |
Journal | Journal of Geophysical Research |
Volume | 116 |
DOIs | |
Publication status | Published - 2011 |