High radar-backscatter regions on Antarctic sea-ice and their relation to sea-ice and snow properties and meteorological conditions

The temporal and spatial variability of sea-ice radar signatures in the Southern Ocean during late winter, spring and early summer from QuikSCAT data is presented. We observe a circumpolar and broad band of sea-ice close to the marginal ice zone that is characterized by very high radar backscatter....

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Bibliographic Details
Published in:International Journal of Remote Sensing
Main Authors: Willmes, Sascha, Haas, Christian, Nicolaus, Marcel
Format: Article in Journal/Newspaper
Language:unknown
Published: Taylor & Francis 2011
Subjects:
Online Access:https://oceanrep.geomar.de/id/eprint/26348/
https://doi.org/10.1080/01431161003801344
Description
Summary:The temporal and spatial variability of sea-ice radar signatures in the Southern Ocean during late winter, spring and early summer from QuikSCAT data is presented. We observe a circumpolar and broad band of sea-ice close to the marginal ice zone that is characterized by very high radar backscatter. This feature is explained through detailed in situ observations of snow and sea-ice properties as well as in relation to meteorological conditions, which were derived from US National Center for Environmental Prediction (NCEP)/National Center for Atmospheric Research (NCAR) reanalysis data. Our results indicate that high backscatter regions are caused by metamorphous snow, which forms through re-freezing after short-term melt events. This process is connected with the episodic passes of low-pressure systems entraining warmer air from the north. South of the Antarctic Circumpolar Trough, sea-ice is not affected by this influence and shows spatially homogenous microwave signatures with low backscatter.