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to di erentiate between the fresher multi-year ice and the higher salinity rst-year ice due to their di erent electromagnetic properties. Figure 1 is a Radarsat-2 HH polarization image (horizontal send and horizontal receive) taken on September 19, 2009 in MClure Strait. In the image, it is di cult to distinguish the multi-year ice from other ice types. By combining horizontal send with vertical receive (HV), the multi-year ice clearly stands out but the thin- ner ice types are not as evident, as seen in Figure 2. Figure 3 depicts a combination of HH, HV, and RGB221, providing an image that clearly illustrates the multi-year ice and thinner ice. Building on technology Scientists have looked at the feasibility of integrating polarization into marine radar systems since the late 1980s; however, limitations in processing technol- ogy did not allow the system to take full advantage of the two polarized signals. In the late 1990s, a prototype system was built using a low-cost radar modified to receive the vertical component of the cross-polarized radar system. An azimuth slaving controller synchronized the radar to rotate at the same speed and angular position as the main radar. The radar system was installed on the Canarctic vessel Arctic for trials in March 2004 in the Arctic. There was evidence that the cross-polarized radar was able to detect and identify multi-year and gla- cial ice. The operator would toggle between the HH and HV images for comparison as the two channels were not completely integrated. e Canadian Coast Guard is building on this tech- nology to develop the ice hazard radar. e intent is to install systems on the other arctic CCG icebreakers and demonstrate to the marine industry how the radar can improve the safety and e ciency of navigation in multi-year ice. Barbara OConnell is an icebreaking program analyst in Canadian Coast Guard Headquarters in Ottawa as well as project manager for the ice hazard radar project. Before coming to Ottawa, she worked as a ships o ceron various Coast Guard vessels, making numerous trips to the Arctic. Marine Ice Hazard Radar continued FIGURE . RADARSAT-2 HH image of MClure Strait FIGURE . RADARSAT-2 HV image of MClure Strait FIGURE . RADARSAT-2 RGB221 image of MClure Strait January 2011 www.sname.org/sname/mt (mt notes)