Classification of CryoSat-2 Radar Echoes - Towards an Interdisciplinary Approach in Earth System Science - page 145

especially for multi-year ice while for first-year ice this bias does not have a

signi cant effect. Therefore we used higher threshold values for the left- and right-

peakiness for

first-year ice waveforms erroneously.
Overall we discarded 22 % of the radar echoes of a CryoSat-2 ground track from
December 15, 2013. Using the multi-year ice thresholds of left- and right-peakiness
for FYI would lead to a rejection of 86 % of the

first-year ice to avoid discarding

first-year ice waveforms because

the shape of first-year ice waveforms is similar to invalid waveforms from multi-

year ice that are biased by off-nadir leads. However, since we rely on the OSI SAF
ice-type product valid

first-year might be underrepresented if indicated as multi-

year ice.

Acknowledgments We thank the European Space Agency for providing the CryoSat-2 data. We
further thank the Earth-System Science Research-School (ESSRES) for any support during this
Phd project. The work of S. Hendricks and V. Helm was funded by the 268 Federal Ministry of
Economics and Technology (Grant 50EE1008). For the usage of images of The Blue Marble: Next
Generation we thank NASAs Earth Observatory.

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