Satellite data acquisition for iceberg monitoring in the Svalbard area

Observation and forecasting of icebergs is an important task for offshore oil and gas development in Arctic regions. For many decades the Russian conducted regular aircraft monitoring of icebergs in Arctic seas, but in the last 15 years only occasional expeditions with icebreakers and aircraft have collected iceberg data in the Barents Sea. Monitoring of icebergs from satellites has been studied in research projects since the early 1990s, but has not yet been implemented as an operational service. New satellite systems are under
development that can improve iceberg detection in the coming years.
This report presents a set of high-resolution satellite images collected in the Svalbard area for iceberg detection in April-May 2007. Several images were taken during the field expedition with Lance north of Svalbard. During the Lance expedition, ICEX buoys with ARGOS transmitters provided by CMR were deployed on four different icebergs. The ARGOS data were used during April and May to follow the four icebergs. Two of the icebergs continued to send ARGOS positions from June to August. Two types of high-resolution satellite images were used: optical images from SPOT, Landsat and Terra ASTER, and Synthetic Aperture Radar (SAR) images form ENVISAT and Radarsat. The optical satellite data are limited by cloud cover. This means that good-quality images can be produced only on days with little clouds. SAR data gives good quality radar images independent of clouds and daylight, but the SAR images
have speckle noise which disturbs the detection of icebergs. For optimal observation of icebergs it is necessary to use both optical and SAR images of resolution 10 m or better. Most of the images are presented in quicklook format, which is useful for an overview and planning the analysis of full-resolution images. In this study, a few examples of full-resolution images are presented. One RADARSAT SAR and one SPOT image covering the positions of the tagged icebergs were analysed in detail. In some cases potential icebergs were found in the images, but in other cases there was no iceberg signal even if iceberg positions were documented by ARGOS data. The size of the tagged icebergs were around 50 m, which is rather small size for detection in the present images. The possibility to detect the known icebergs in the satellite images depends on several factors such as the ice conditions around the icebergs, the size and shape of the icebergs and resolution of the satellite images.

This study has demonstrated how satellite data collection for iceberg monitoring can be done for the Svalbard area. More information about icebergs in this area can be obtained if the images are analysed in full-resolution. In particular several of the 35 SPOT images are expected to give more data on icebergs in the Hopen and Kong Karls Land area. This area was also covered by high-resolution SAR images in alternating polarization images. Also the area around Nordaustlandet have icebergs that potentially can be detected in the images. Future schemes for iceberg monitoring should include use of new high resolution SAR images with full polarization, optical images, airborne surveys with fixed-wing aircraft or helicopters, and deployment of Argos buoys on selected icebergs