Ice map produced for the prevention of ice jam floods and the monitoring of river ice during spring floods, winter temperatures or even during frasil ice jam problems. Radarsasat-2 images are obtained through a partnership between Public Safety Canada and the MSP, facilitated through the Saint-Laurent Action Plan. It is now possible for regional civil security advisors to order Radarsat-2 images through the Government Operations Centre. These are processed and disseminated into ice maps that are used to monitor, manage and respond to a risk of ice jam or ice jam flooding. Radarsat-2 is a next-generation Canadian commercial radar satellite that offers powerful innovative technical capabilities that facilitate maritime surveillance, ice monitoring, disaster management, environmental monitoring, resource management, and mapping activities in Canada and around the world. The modes used for the acquisitions are as follows: high resolution with HH HV cross polarization. The width of an image is then 50 km and the resolution is 9 m. Very high resolution with HH polarization. The width of an image is then 20 km and the resolution is 3 m. The images produced by Radarsat-2 are delivered to the MSP and processed by the geomatics team of the Information Technologies Directorate. This treatment, carried out using an algorithm developed by the remote sensing laboratory of the National Institute of Scientific Research (INRS), Centre Eau Terre Environnement, allows the ice map to originate. The algorithm developed by INRS makes it possible to identify the type of ice according to the internal roughness of the ice (presence of air bubbles) and the roughness of the surface of the ice cover (presence of blocks and pilings). The different classes in the legend allow the following types of ice to be identified: Black ice: the exact term for this type of ice is “columnar ice”, due to the vertical and elongated shape of the crystals that compose it. Black ice is generally transparent because it contains few or no air bubbles. It is formed by cooling, in fairly still water, which is why it is sometimes called “thermal ice”. Its surface is very smooth. White ice: it includes frasil ice or snow ice. Frasil ice is formed in turbulent, very cold water. Composed of fine rounded crystals. These grains accumulate and rise to the surface to form moving ice rafts. These rafts end up being close enough together to freeze together (agglomerated ice). Contains lots of air bubbles. Its surface is slightly to moderately rough. Snow ice is usually formed by the freezing of snow that has been inundated either by rain or by a resurgent flow of water onto the ice. Consolidated ice: covered with ice formed by the stacking and freezing of various forms of ice in motion. These may be rafts that are superimposed or pieces of ice that are detached in one place and piled up in another. Moderately rough to very rough surface. Two legends are used depending on the current season and according to the state of degradation of the ice: a winter legend and a spring legend. Since 2018, the MSP has also been using images from Sentinel-1, a radar satellite of the European Space Agency. Sentinel acquisitions are very wide and cover about 100 km, the resolution is 10 m. The images are then processed by the firm Dromadaire Géo-Innovation and delivered to the MSP. LIMITATIONS: the ice map is the result of an automated radar satellite image processing process. This process involves interpretive uncertainties that may be related to the climatic conditions that prevailed when the image was acquired or by the physical characteristics of the watercourse (presence of shoals, islands or rapids). They also depend on the resolution of the initial images. Thus, although the ice map created is representative of reality, there may be some errors in identifying ice conditions at the local level. The use of the product is optimized when combined with field observations. Purpose: The type of ice present, frasil, ice packs, ice jams, and open water channels can be identified using images taken by Radarsat-2. At a single glance, you get an accurate portrait of the situation over an entire watercourse. Thus, satellite images represent a decision-making tool. For example, they make it possible to identify, even through snow, the sectors where the ice cover is the most fragile and, therefore, to carry out preventive work on the ice covers in order to prevent the risk of flooding. In addition, during winter temperatures or spring melts, radar images are used to monitor the formation of ice jams and the movement of ice along rivers during breakdowns. This allows Civil Security and municipal authorities to coordinate the measures to be taken more effectively.**This third party metadata element was translated using an automated translation tool (Amazon Translate).**