Potential of RADARSAT-2 data for operational sea ice monitoring Bernd Scheuchl, Dean Flett, Ron Caves, and Ian Cumming Abstract. Synthetic aperture radar (SAR) data from RADARSAT-1 are an important operational data source for several ice centres around the world. Whereas RADARSAT-1 is only capable of acquiring data at a single polarization, RADARSAT-2 will be capable of acquiring dual-polarization data in many wide-swath modes (most importantly ScanSAR) and fully polarimetric SAR data in a narrow 25-km swath mode. In this paper, we consider the ice information requirements for operational sea ice monitoring at the Canadian Ice Service and the potential for RADARSAT-2 to meet those requirements. Primary parameters are ice-edge location, ice concentration, and stage of development; secondary parameters include leads, ice thickness, ice topography and roughness, ice decay, and snow properties. Iceberg detection is included as an additional ice information requirement. The dual and fully polarimetric modes of RADARSAT-2 are expected to enhance our ability to measure these parameters. For ice operations, the dual-polarization data are expected to be most useful, as they will provide the required wide coverage in a number of modes. Although ScanSAR is the recommended mode of operation, the properties of other modes are also discussed. To illustrate the expected improvements from polarimetry, we review the conclusions of past work and add some new results using ENVISAT ASAR and simulated RADARSAT-2 data. Résumé. Les données RSO de RADARSAT-1 constituent une source de données opérationnelles importante pour plusieurs services des glaces autour du monde. Alors que RADARSAT-1 n’est capable d’acquérir des données qu’en fonction d’une seule polarisation, RADARSAT-2 sera capable d’acquérir des données en polarisation double, dans plusieurs modes à faisceau large (le plus important étant le mode ScanSAR) et des données RSO polarimétriques dans un mode faisceau étroit de 25 km. Dans cet article, nous examinons les besoins en information sur la glace pour le suivi opérationnel de la glace de mer au Service canadien des glaces et la capacité de RADARSAT-2 à combler ces besoins. Les paramètres primaires sont la localisation de la limite de la glace, la concentration de la glace et le stade de développement de la glace alors que les paramètres secondaires comprennent les chenaux, l’épaisseur de la glace, la topographie et la rugosité de la glace, la désagrégation de la glace et les propriétés de la neige. La détection des icebergs est incluse à titre de besoin additionnel au plan de l’information sur la glace. Les modes en polarisation double et polarimétrique de RADARSAT-2 devraient améliorer notre capacité à mesurer ces paramètres. Pour les opérations sur la glace, les données à polarisation double devraient être très utiles étant donné qu’elles fourniront la couverture large requise pour un certain nombre de modes. Quoique le mode ScanSAR soit le mode d’opération recommandé, on discute également des propriétés des autres modes. Pour illustrer les améliorations prévues au plan de la polarimétrie, nous passons en revue les conclusions de travaux antérieurs et nous présentons de nouveaux résultats à l’aide des données ASAR d’ENVISAT et des données simulées de RADARSAT-2. [Traduit par la Rédaction] 461 Introduction RADARSAT-1 has been a primary source of synthetic aperture radar (SAR) data for sea ice monitoring since it became operational in 1996. This has revolutionized the way in which several national ice monitoring agencies now operate. For example, the United States National Ice Center (NIC) use of RADARSAT-1 data has approached 6000 scenes annually to meet their global ice mapping objectives, and the Canadian Ice Service (CIS) has consumed, on average, between 3500 and 4500 scenes annually covering Canadian waters. With the future launch of RADARSAT-2, the CIS is looking forward to continuity of RADARSAT-1 data to meet its operational needs. RADARSAT-2 will offer the entire suite of legacy beams of RADARSAT-1. Besides data continuity, RADARSAT-2 promises several enhancements to the payload and the space and ground segments (see this RADARSAT-2 special issue of the Canadian Journal of Remote Sensing, Vol. 30, No. 3). Ramsay et al. (2004) summarize the potential benefits of a number of these enhancements for operational ice monitoring. The space segment will offer higher resolution, multiple polarization, and fully polarimetric modes. The capability of RADARSAT-2 to measure two or four polarizations is expected to enhance the measurement of parameters (e.g., ice-edge location, ice concentration, stage of development) that are important for operational ice monitoring. The focus of this paper is on the potential of some of these modes for meeting operational ice information requirements, with an emphasis on dual polarization. 448 © 2004 CASI Can. J. Remote Sensing, Vol. 30, No. 3, pp. 448–461, 2004 Received 13 June 2002. Accepted 16 January 2004. B. Scheuchl 1 and I. Cumming. Department of Electrical and Computer Engineering, University of British Columbia, 2356 Main Mall, Vancouver, BC V6T 1Z4, Canada. D. Flett. Canadian Ice Service, 373 Sussex Drive, E-3, Ottawa, ON K1A 0H3, Canada. R. Caves. MacDonald Dettwiler and Associates Ltd., 13800 Commerce Parkway, Richmond, BC V6V 2J3, Canada. 1 Corresponding author (e-mail: bscheuch@mda.ca).