| Title | Cryosat delivers monthly and inter-annual surface height change for Arctic ice caps |
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| Author | Gray, L; Burgess, D ; Dunse, T; Langley, K; Copland, L |
| Source | American Geophysical Union, annual fall meeting, abstracts; 2014 p. 1 |
| Links | Online - En ligne
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| Year | 2014 |
| Alt Series | Earth Sciences Sector, Contribution Series 20140360 |
| Publisher | American Geophysical Union |
| Meeting | American Geophysical Union, Fall meeting; San Fransisco; CA; December 15-19, 2014 |
| Document | book |
| Lang. | English |
| Media | on-line; digital |
| File format | html |
| Province | Nunavut |
| NTS | 26 |
| Area | Barnes Ice Cap; Baffin Island |
| Lat/Long WENS | -72.0000 -64.0000 68.0000 64.0000 |
| Subjects | environmental geology; surficial geology/geomorphology; Nature and Environment; ice; ice conditions; ice thickness; climate effects; climate, arctic; precipitation; snow |
| Illustrations | graphs |
| Program | Climate Change Geoscience Essential Climate Variable Monitoring |
| Released | 2014 01 01 |
| Abstract | The Cryosat (CS) radar altimeter provides estimates of surface height change, including summer melt and winter snow accumulation, from some Arctic ice caps. The Barnes Ice Cap on Baffin Island, Canada
represents the most straightforward situation; essentially snow over ice at all elevations. As illustrated below, the average summer height losses on Barnes were 1.69 ± .36 m (2011), 2.39 ± .36 m (2012), and 1.44 ± .37 m (2013), values which were not
balanced by the winter snow accumulation; 0.77 ± .39 m (2011/12), 0.93 ± .33 m (2012/13) and 1.19 ± .43 m (2013/14). However, results from most Arctic ice caps are more complicated: For example, Austfonna in the Eurasian Arctic has a maritime climate
with relatively high accumulation and winter conditions that can vary from very cold to rain. Consequently, the distribution of different snow and ice zones varies with position, elevation and time. This leads to a complicated and varying bias
between the heights estimated from the radar altimeter waveforms and the physical surface. Nevertheless, under melting conditions the radar returns are dominated by surface backscatter so that observations at the beginning and end of each melt season
can provide estimates of net winter accumulation and summer height loss. Results for two Cryosat calibration-validation sites; the Devon Ice Cap in Canada and Austfonna on Svalbard, will be compared with surface and airborne data. Also, estimates of
the height and volume change associated with the current surge of basin 3 in Austfonna, which began in earnest in the summer of 2012, will be shown. |
| Summary | (Plain Language Summary, not published)
Preliminary analysis of data from the Cryosat radar altimeter reveal significant annual height changes of some large ice caps in the Canadian high
Arctic. We also demonstrate that the frequent coverage by Cryosat over high latitude ice caps allows us to detect seasonal changes in ice mass, and therefore to discriminate between mass loss (summer melting) and mass gain (winter
accumulation). |
| GEOSCAN ID | 295651 |
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