Airborne Sea Ice Campaigns in Support of the ALOS Mission
(1) Alfred Wegener Institute, Bussestr. 24, D-27570 Bremerhaven, Germany
In the last decade, three field campaigns were carried out
in the region of Svalbard, during which airborne synthetic aperture
radar (SAR) images were acquired over sea ice. L-band was one of the
frequency modes that were used. The airborne SAR systems that
were utilized are the German ESAR (2005 and 2007) and the
Danish EMISAR (1998). In all cases, optical images were
gathered by airborne scanners. Examples of sea ice radar signatures
at L-band will be presented for different ice conditions and
compared to C-band data which are available for the campaigns
of 1998 and 2007. Pros and cons of different polarizations at
L-band for operational sea ice analysis will be discussed.
The effect of noise level and spatial resolution of the imagery
will be considered.
Another campaign that was carried out in May and June 2008
in the Canadian Arctic was focussed on sea ice characteristics
under melting conditions. Images from different satellite SAR
systems (ALOS PALSAR, TerraSAR-X, Envisat ASAR and Radarsat-2)
were ordered. Optical scanner data were acquired from an airplane.
A first analysis of the ALOS data will be presented, focussing on pros
and cons of monitoring melting sea ice with L-band SAR in comparison
to higher radar frequencies.