Main problem for scheduling vessel transit voyages through the Northern Sea Route is the difficulty in predicting distribution of ice boundaries in regions that cannot be overcome by individual ice classes of vessels. Scheduling of voyage is related to speed that vessels can develop and moment of time when vessels will be able to commence and complete passage safely through areas that are main obstacle and are blocking longest transit passage through the Northern Sea Route. This applies to voyages carried out by vessels navigating on their own and with support of icebreakers. Additional problem is lack of consistency of content of maps of ice cover, which can be used for vessels voyage planning through areas where ice cover occurs. Results of this research on influence of uncertain information related with time window of conditions favorable for navigation of vessels of different ice classes on schedule of theirs voyage on example of summer navigation season 2017 are presented in this work.
The research on the ice cover of waterways, rivers, lakes, seas and oceans by satellite remote sensing methods began at the end of the twentieth century. There was a lot of data sources in diverse file formats. It has not yet carried out a comparative assessment of their usefulness. A synthetic indicator of the quality of data sources binding maps resolution, file publication, time delay and the functionality for the user was developed in the research process. It reflects well a usefulness of maps and allows to compare them. Qualitative differences of map content have relatively little impact on the overall assessment of the data sources. Resolution of map is generally acceptable. Actuality has the greatest impact on the map content quality for the current vessel’s voyage planning in ice.
The highest quality of all studied sources have the regional maps in GIF format issued by the NWS / NOAA, general maps of the Arctic Ocean in NetCDF format issued by the OSI SAF and the general maps of the Arctic Ocean in GRIB-2 format issued by the NCEP / NOAA. Among them are maps containing information on the quality of presented parameter. The leader among the map containing all three of the basic characteristics of ice cover (ice concentration, ice thickness and ice floe size) are vector maps in GML format. They are the new standard of electronic vector maps for the navigation of ships in ice.
Publishing of ice cover maps in the standard electronic map format S-411 for navigation of vessels in ice adopted by the International Hydrographic Organization is advisable in case is planned to launch commercial navigation on the lagoons, rivers and canals. The wide availability of and exchange of information on the state of ice cover on rivers, lakes, estuaries and bays, which are used exclusively for water sports, ice sports and ice fishing is possible using handheld mobile phones, smartphones and tablets.
Vessels designed for navigation in ice can perform voyage with the assistance of icebreaker in the navigation season in case an ice cover area is less than 20%. Whereas the same vessels could carry out successfully completed voyage through the NSR with intensive icebreaker help at the ice-covered area lower than 42%. Navigation of the same vessel at ice covered area above 80% is possible with intensive icebreaker help, but it threatens to damage the hull, rudder or propeller.
Excessive generalization of data analyzed may cause to wrong, even opposite conclusions. Using only basic statistical information in the form of average values and standard deviation may be not sufficient for the purpose of vessel’s voyage planning in areas covered with ice. Much more opportunities for the assessment of navigation in ice covered regions provides cumulative distribution, which should be related to the time and geographical space distribution. It allows to determine the duration of time window for given area covered with ice in a particular region and predetermined probability of its occurrence. It is thus possible to plan approximate date of departure and duration of voyage for assumed safety criteria. Also, it is possible to plan a number of consecutive voyages in a navigation season.
Mathematical approach to voyage planning in ice based on a cumulative distribution is presented in the paper. It allows creation of an advisory computer application to support decision-making by the commander of a vessel. It will reduce the human factor in data processing and reduce possibility of making a mistake. By this way, can be enhanced the safety of maritime transport. Novell approach is verified on the example of historical data about the German Navy ship activity during the Second World War.
Information about the condition of ice cover on surface of the water, which are the content of map, are important for carrying out safe navigation and efficient economic activity in the polar regions. Methods of mapping can be fully automated on the basis of developed through years of experience algorithms or additionally supported by experienced professionals. The content of some of those now commonly encountered maps is compiled on the basis of mixed methods. In this work geographic positions of ice maps content are analyzed taking into consideration their usefulness for planning ship’s voyage in ice. The results of this work allow using the contents of studied maps for determining the ship’s route in ice and voyage planning of the ship in ice according to her hull strengthening.
The ice maps often have boundary lines for different values of reference. The maximum width of the strips of each boundary line within the Marginal Ice Zone is 100 km. The mean square error of position of the analyzed maps is +/− 2.0 km. Average locations of boundaries are consistent except for GRIB type maps of the OSI SAF and NIS, which seem to indicate much lower value of ice floe concentration. The NIC MIZ maps and S-411 standard maps are consistent for the 13% and 81% concentration. The 40% limits on MASIE maps and 46% limits of concentration on S-411 standard maps are also consistent. The course of ice edge issued by the NIS for the GMDSS METAREA, 19 region visualizes well the boundaries of the area where the ship might encounter any form of ice. Information of the GMDSS METAREA 20 region issued by the AARI represents the average of the limits 1 to 46% of all sources of information, and on average the 13% limit of ice concentration. The one-year old ice limit with thickness of 0.10 to 0.30 meters on the AARI map is consistent with course and average location of boundaries of 81% ice concentration on the NIC MIZ map and S-411 standard map. The multi-year old ice limit of thickness from 0.30 to 2.00 meters on the AARI map is coincident with the 79% limit of concentration displayed on the NIS map.
The work discusses possibility to make transit voyages of vessels without ice strengthening on the Northern Sea Route (NSR). Exist many uncertainties for it. They are related to hydro-meteorological conditions, mostly to ice cover on the Russian Arctic. Ice conditions are under dynamic changes in time and space. Is hard to precisely predict ice conditions now, in the time range of one month and so on. Statistical historical data of daily changes same like yearly changes show a considerable scatter of the data. The author analyzed number of ice-free days of particular seas of the NSR in the latest eight years. The results of this work may be used for estimation of time frame (time window) for transport of cargo on the NSR by means of vessels without ice strengthening. The statistical presentation of ice-free days data was used in the work to develop decision supporting method related to planning vessel voyage including ice-free time frame on particular seas of the Northern Sea Route.
Statistical studies of marine accidents and unfortunate events in ice-covered areas in 1995–2004 and 2004–2011 showed a general lack of information from the area under the jurisdiction of the Russian Federation. The author’s research for the period 2004–2011 showed a large number of unfortunate events caused by lack of adequate provision of nautical charts, shortage of accurate position systems on board vessels as well as weak technical condition of these vessels. The author examined the problem of navigation safety on the Northern Sea Route in terms of availability of the official nautical charts and publications.
The availability of official nautical publications supplied by global producers is more diverse and ambiguous than it is in case of nautical charts. Surprising is lack of Russian publications related to tides and unavailability of a guide for planning routes on Northern Sea Route issued by Russia in Russian and English languages.
Global producers of official charts and nautical publications do not provide full range of information and recommend vessels the use of the products supplied by Russia. These products are issued in Russian. This is a serious impediment to their use and thus introduces privilege of ships’ crews who speak Russian.
Northern Sea Route leads through regions that are not sufficiently explored. The Northern Sea Route Administration recommends guiding ships only on designated routes marked on maps and described in nautical publications. The currently hydrographic work is focused on determining new routes according to the spatial distribution of the ice massifs during the navigation season. However, this does not solve the problem of a comprehensive exploration of the Russian Arctic regions for the purpose of safe navigation on the customized routes.