Navigation in ice is a great challenge as well as experience. One may handle the icy conditions on an ice strengthened ship, having done a specialised course on ‘Ice Navigation’, ‘High Latitude Navigation’, etc., though, on the other hand one might simply encounter ice, unprepared for the difficulties. To operate the ships within an ice area, whether it is the multiyear ice or a first year ice, requires specialised knowledge and skill. With higher awareness and higher implementation of safety than the past years; and with continuous monitoring and encouraging initiative of IMO, a mariner and his ship are likely to be well suited to undertake the navigation in ice.
IMO’s International Code for Ships Operating in Polar Waters (Polar Code) is mandatory under both, the International Convention for the Safety of Life at Sea (SOLAS) and the International Convention for the Prevention of Pollution from Ships (MARPOL). The Code covers matters relevant to ships operating in the inhospitable waters surrounding the two poles. Covered matters include, the full range of design, construction, equipment, operation, training, search and rescue and environmental protection. The Polar Code entered into force on 1st January 2017.
The Master of a ship, when ice is reported on or near his track, is required to proceed at a moderate speed and with extreme caution, particularly at night. He must, if necessary alter course to pass well clear to the danger zone. The International Convention for the Safety of Life at Sea (SOLAS) requires the Master to make a report regarding the type, position, and time/date of observation of ice. Also severe wind, causing ice accumulation on deck, with the position of ship & the GMT time, must be reported.
Structured, simulator courses are available in various training centres. Chapter 12 of the Polar Code on manning and training says that, ‘companies must ensure that Masters, chief mates and officers in charge of navigational watches onboard ships, operating in polar waters, have completed appropriate training, taking into account the provisions of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) and its related STCW Code. Mandatory minimum requirement for the training and qualifications of Masters and deck officers on ships operating in polar waters were also adopted by IMO’s Maritime Safety Committee in November 2016. They became mandatory under the STCW Convention and the STCW Code from 1st July 2018.
A specialized course could be for deck officers, pilots, superintendents and VTS operators. The course can include the information in respect of navigational characteristic of sea ice; ice charts; ship preparation for ice; communications in ice; the ice breakers, mooring & advanced ice navigation techniques; interaction of ship’s hull, CPP, FPP and other propulsion systems in ice; team work in difficult ice conditions; etc. Some of the specialised value added courses already available in different countries were; ‘Professional Ice Navigation Training’, ‘Advanced Ice Navigation Training’, ‘Practical Ice Navigation Training’, ‘Crew Resource Management in Ice Navigation’, etc.
The Polar Code is intended to cover the following:
- full range of shipping-related matters relevant to navigation in waters surrounding the two poles;
- ship design, construction and equipment; operational and training concerns; search and rescue; and
- equally important, the protection of the unique environment and eco-systems of the polar regions.
The Polar Code includes mandatory measures covering safety part (part I-A) and pollution prevention (part II-A) and recommendatory provisions for both (parts I-B and II-B). The Code will require ships intending to operate in the defined waters of the Antarctic and Arctic to apply for a Polar Ship Certificate, which would classify the vessel as:
1. Category A ship – ships designed for operation in polar waters at least in medium first-year ice, which may include old ice inclusions;
2. Category B ship – a ship not included in category A, designed for operation in polar waters in at least thin first-year ice, which may include old ice inclusions; or
3. Category C ship – a ship designed to operate in open water or in ice conditions less severe than those included in Categories A and B.
The issuance of a certificate would require an assessment, taking into account the anticipated range of operating conditions and hazards the ship may encounter in the polar waters. The assessment would include information on identified operational limitations, and plans or procedures or additional safety equipment necessary to mitigate incidents with potential safety or environmental consequences.
Ships are required to carry a Polar Water Operational Manual, to provide the Owner, Operator, Master and crew with sufficient information regarding the ship’s operational capabilities and limitations in order to support their decision-making process.
The chapters in the Code, set out goals and functional requirements. The various areas covered include: ship structure; stability and subdivision; watertight and weathertight integrity; machinery installations; operational safety; fire safety/protection; life-saving appliances and arrangements; safety of navigation; communications; voyage planning; manning and training; prevention of oil pollution; prevention of pollution form from noxious liquid substances from ships; prevention of pollution by sewage from ships; and prevention of pollution by discharge of garbage from ships.
Ship routing measures
The MSC, in May 2018, adopted new and amended ships’ routing measures in the Bering Sea and Bering Strait, aimed at reducing the risks of incidents. The measures include six two-way routes and six precautionary areas, to be voluntary for or all ships of 400 gross tonnage and above, in the Bering Sea and Bering Strait. These are proposed by the Russian Federation and the United States. These waters are expected to see increased traffic due to rising economic activity in the Arctic. In addition, the MSC established three areas to be avoided in the Bering Sea, proposed by the United States, to improve safety of navigation and protect the fragile and unique environment. These measures entered into force on 1st December 2018.
A Master out at sea, hates fog during navigation and fears encountering unexpected ice at sea and definitely does not want to be the first one to spot an iceberg. The awareness however, is quite high regarding presence, movement, etc of ice. Information regarding the possibility of ice must be gathered from:
1. Routing charts,
2. Ice weather reports by International Ice Patrol, etc. &
3. Safety messages.
A detailed information and guidance is often provided by the ports facing such severe ice conditions, which must also be taken into consideration. Following is a typical text of guidelines provided by an ice port.
- The sea water freezing point of the brackish water in this port is about – 0.4° C. The ice thickness is about 0.5 – 0.7 m in an average winter. The biggest obstacles to winter navigation are ridges which are normally thicker than the level ice and are difficult to penetrate. Channels with thick side ridges and thick brash ice in the middle are formed when the ice cover in the fairway is repeatedly broken and frozen. The side ridges make passing of other vessels very difficult. Ridges also form when winds push ice together.
- The beginning and the end of ice navigation at the ports is stated in the formal order issued by the Harbour Master.
- Ice navigation is permitted for ice-classed vessels or at least with the confirmation of classification society to navigate in the concrete ice conditions in each particular case.
- The ice breaker convoy is a compulsory requirement for navigation in ice conditions.
- There is no local requirement for a ship to be weather routed when navigating these areas in ice condition. But the Master may obtain and monitor the weather reports from our website.
- The Master must submit a written application for an ice-breaker convoy, to the Harbour Master.
- Where, there is any possibility for the vessel being sent to any of the ice-bound ports, on her arrival or where the onset of ice may cause the Master, to decide to leave the port before cargo operations are completed, the suitable ICE Clause should be included in the charter party and in bills of lading.
There have been many publications, providing guidelines to the vessels operating in ice covered waters. They can be a good source of relevant information on ice. Some of them being; Guidelines for Ships Operating in Arctic Ice Covered Waters, by IMO; Arctic Water Pollution Prevention Act of Canada; Rule for Winter Navigation of Finland; Russia and Baltic States Ice Navigator Standards by Captain Snider; Chapter 8, Ice of ‘The Mariners Handbook’, and ‘Chapter 33, ‘Ice Navigation’ of The American Practical Navigator; ‘Ice Navigation in Canadian Waters’ by The Canadian Coast Guard publication; etc. There are special publications for the Antarctic Waters viz. Specific Requirements for Shipping in Antarctic Waters of GAUSS publication; and Antarctic Shipping Guidelines by Captain George Q Parnell;
Ice may be encountered in various forms out at sea. Right from drifting icebergs, bergy bits & growlers to pack ice. The proximity of ice calls for a special attention in navigation. Cautionary measures are essential in the management of navigation and the seamanship procedures. Following are some of the guiding tips in this respect:
- Watchkeeper must report any signs of presence of ice viz. ice blink, isolated fog patch with supporting signs, etc. to Master.
- Erect or inverted image of an iceberg may be seen due to super refraction. Such an image of ice is likely to be of a magnified size.
- Seawater temperature must be recorded more frequently than normal. The frequency will depend upon the possibility of proximity of ice. Steep fall of temperature must be taken seriously, as an indication of possibility of presence of ice. A surface temperature of -0.50C normally should imply the proximity as less than 50 miles.
- The calving of icebergs, cracking and falling into sea creates a thunderous roar. The echo of a ship’s whistle may or may not be heard.
- A sudden drop in strength of sea associated with a drop in air temperature and visibility may also indicate presence of ice, especially from the side, from where swell was coming, strength of which is damped now.
- Icebergs are sometimes not detected at a high range owing to smooth, sloping surface, poor reflecting material etc. Some of the navigationally dangerous bergy bits may not be detected over more than 3 miles from the ship. A sharp look out visually & on radar must be maintained.
- In fog or dense mist an iceberg may shine like a luminous object, if sunlight falls on it. On the other hand on a clear night no iceberg may be sighted at more than 1 or 2 miles. On a moonlit night an iceberg is more easily seen if moonlight falls on it from behind the observer.
- On a clear day, with sky mostly blue, ice blink appears as a luminous yellow haze on the horizon in the direction of the iceberg. The height of the blink depends on the proximity of the ice field. Ice blink is exhibited by consolidated & extensive ice field.
- Close to land, the topographical features may be modified due to ice stuck to the land. The mariner must therefore cross check radar’s position-fixing by other means also.
- If two radars are on, then one of them must be kept on 6 miles range scale, tuned for detecting ice. The other radar must be on a suitable higher range. Large icebergs may be detected 20 miles off. Bergy bits smaller but still dangerous to ship may not be detected till about one mile off. A clutter caused by choppy sea can eclipse dangerous bergy bits. In the Antarctic, the Antarctic Petrel and Snow Petrel are said to indicate the proximity of ice.
- Speed of ship must be moderate only, especially at night in the ice area.
- Ice fields in general must be avoided but some ports in winter may have pack ice or pancake ice of varying thickness for miles around the entrance and thus ice encounter may be inevitable.
- When ice field entry is inevitable, the Master must consult owners and communicate with charters and also consult the charter party. He must act with caution with all the safety required, also protecting the owner’s interest.
- The ice field must be entered only with caution and appropriate preparedness. The following factors are considered:-
1. Routes, if maintained by shore authorities (ice breakers etc.) can be used.
2. Thickness of cake ice.
3. Type of ice field, closed pack or open pack, etc.
4. Trim of ship: extra trim would help:
a. Positive immersion of propeller blades,
b. Break ice by gradually landing the stem over ice than by hitting it head on.
5. Waiting period & the stay period in the port.
6. Possibility of alternative load / discharge port.
7. Power of ships, type of engines, draft & maneuverability of ship. A ship of less than 12kn, not strengthened for ice, is likely to become firmly beset in the ice.
8. Extension of ice field and its status, whether the growth of ice is on the incline or is on the decline.
Reliability of navigational and communication equipment is of great importance. While maneuvering in ice field, cake ice may be in separate clusters. A new cluster must be approached, as slowly as possible and once in contact with the cake ice, full power may be required to continue the headway.
Allowance must be made to normal collision avoiding principles. Intermediate ice often acts as a fender between two ships in close proximity. On the other hand, a low powered ship while crossing from one side to other may suddenly stop ahead of your ship in want of sufficient engine power.
Continuous lookouts are maintained and the lookout person is briefed about the kind of reporting that is expected of him.
While the ship steers through close pack ice, a large amount of ice is broken fine with the body of the ship. These broken pieces are driven off on either side of propeller at stern. Many pieces travel from under the ship’s keel and then rise to the surface just abaft the propeller. This is one of the reasons why sudden astern propulsion may damage the propeller and must be avoided. Fairway buoy and channel-marking buoys may be removed or adrift due to tidal movement of ice.
There are numerous incidents of losing anchor, broken propeller blades etc. While waiting in a bay or an anchorage area of tidal stream with pancake ice, it may be a good idea not to anchor at all. During change of tide, entire caked surface tends to move out of the harbour and then towards the harbour on the next tide.
Stability related precautions: Effect of ice accretion on exposed deck is considered. (refer to the Intact Stability Code).
Seamanship related precautions: Cold climate precautions regarding ballast tanks (keep more than 10% space for expansion), fuel oil tanks, fresh water tanks (ease to about 90%), deck water line, life boat’s FW containers, deck ice, windlass, hydraulic lines, safety at work-place and warming of living places etc. are all attended to. Good searchlights are required for night navigation. Gale forces in combination with -20C and below, would require an alteration of course to the warmer area. Leads through the ice are very useful but the one leading ashore must be avoided. The ship’s propeller and rudder must be operational all the time. Once the ship is beset in ice, ship may have to move with the ice. Serious pressures may be caused by ice on the ship’s hull or bottom. Sometimes, change of trim / list may be tried out to release the ship from the ice.
Performance of navigational aids such as coloured lights, sector lights, etc. may be affected by ice on the screen.
When navigating under the assistance of icebreaker, the procedure to be followed by escorted vessel, communication methods between the ships, etc. must be understood well and duly followed. Towing gear is kept ready and rigged. Although, a large number of vessel (14 vessels lost and 40 seriously damaged) due to ice, during the turn of the 19th century, it took one of the greatest marine disasters of all times to arouse public demand for international cooperative action to deal with the hazard cause by ice.
(You may also visit my youtube videos @captsschaudhari.com)