THE TITANIC— 50 YEARS LATER 



life, icebergs continually emit weird sounds as if the ice is being 

 alternately contracted then expanded. 



A warm rain will have a marked affect on the surface of an 

 iceberg. If the temperature becomes higher, melting water will 

 cascade from a berg as a brook hurtling down a mountain side, 

 cutting ever-deepening furrows into its surface. Possibly at night 

 with a drop in temperature, water that seeped into cracks and crev- 

 ices during the day may freeze. Sun's rays produce still another 

 temperature gradient, causing a different amount of expansion to a 

 piece of ice that may already have internal stress caused by slight 

 variations in density and composition. These new forces, slight as 

 they may be, might possibly be enough to cause calfing along internal 

 natural cleavage planes. Although an iceberg in a solid state is almost 

 indestructible, when it becomes rotten it may be completely broken 

 up, under certain conditions, by relatively small external forces. 



Drifting southward in the Labrador Current along the eastern 

 slope of the Grand Banks an iceberg is usually in water temperatures 

 lower than 35 °F and disintegrates very slowly. In the mixed waters 

 off the Tail of the Banks the dissolution is accelerated by water 

 temperatures above 36 °F. However, when the water temperatures 

 reach 50°F the change can be observed from hour to hour. In the 

 mixed waters southward of the Grand Banks the average medium- 

 sized berg will survive as a menace to navigation for a period of 12 

 to 14 days during April, May, and June, but no longer than 10 to 12 

 days thereafter. Should the same berg drift even farther southward 

 into the 65° to 70 °F temperature of the Gulf Stream it would prob- 

 ably survive no longer than 7 days. 



HISTORY OF THE ICE PATROL 



The institution of an efficient patrol and warning system for the 

 critical iceberg area was evolved with the perfection of the marine 

 radio which enabled vessels to communicate freely with others within 

 a reasonable distance. Immediately after the TITANIC disaster, 

 upon the recommendation of the Hydrographic Office, the U.S. Navy, 

 in the interest of safety of life at sea, dispatched a cruiser on 19 May 

 1912 for patrol duty near the ice regions of the North Atlantic. 

 Primarily, the purpose of the patrol was to locate icebergs and field 

 ice nearest the trans -Atlantic shipping lanes, patrol along the 

 southern limits of the ice, and endeavor by radio communications to 

 inform ships in the vicinity and the Hydrographic Office of these 

 conditions. To cover effectively as large an area as possible, vessels 

 were requested to report by radio observed ice conditions to the 

 patrol ship. The Hydrographic Office and its Branch Offices in 

 Boston and New York promptly disseminated the daily reports along 

 the eastern seaboard. Circumstances did not permit the Navy to 

 undertake a patrol of the ice regions the following season. Conse- 

 quently, the 1913 patrol was carried out by revenue cutters of the 

 United States Treasury Department and by the British steam trawler 

 SCOTIA. The ice information received daily by the Hydrographic 

 Office was published in the Daily Memorandum and the Weekly 

 Hydrographic Bulletin and was also disseminated daily by the Branch 

 Office in New York. 



The subject of protecting trans-Atlantic shipping from the ice 

 menace was thoroughly discussed by the first International Confer- 



ence on "Safety of Life at Sea", convened in London on 12 November 

 1913 as a result of the TITANIC sinking. Representatives of the 

 various interested maritime powers signed an agreement on 20 Jan- 

 uary, 1944 providing for the inauguration of an international derelict 

 destruction, ice observation, and ice patrol service. This triple 

 service, consisting of two vessels, was conceived to patrol the ice reg- 

 gions during the season of danger from icebergs and attempt to keep 

 the trans-Atlantic lanes clear of derelicts during the remainder of 

 the year. The United States was invited to undertake the service 

 for which the expenses were to be defrayed in agreed fixed proportions 

 by the nations signing the agreement. Thus, the patrol became 

 international in character when the Revenue Cutter Service (now 

 the United States Coast Guard) began the 1914 patrol. 



Upon the subject of trans-Atlantic lanes, the Conference also 

 adopted the following: "The selection of the routes across the North 

 Atlantic in both directions is left to the responsibility of the steam- 

 ship companies, nevertheless the High Contracting Parties undertake 

 to impose on these companies the obligation to give public notice of 

 the regular routes which they propose their vessels should follow, and 

 of any changes which they make in them. The High Contracting 

 Parties undertake, further, to use their influence to induce owners 

 of all vessels crossing the Atlantic to follow as far as possible the 

 routes adopted by the principal companies." 



Each year as soon as reports from the northern waters indicated 

 icebergs were beginning to drift southward, a cutter would be dis- 

 patched to the Tail of the Banks. Arriving on station the Coast 

 Guard Cutter would notify the various radio stations and vessels in 

 the vicinity of the official commencement of the International Ice 

 Patrol. Thereafter, ice reports would be broadcast on several fre- 

 quencies twice daily and forwarded to the U.S. Navy Hydrographic 

 Office. Two cutters alternated in a continuous patrol, remaining on 

 station about 2 weeks each. The patrol located and guarded the 

 southern ice limits, giving particular attention to the critical ice area 

 between the Tail of the Banks and the westbound B-track, constantly 

 in use throughout the ice season. Serious ice conditions are likely 

 to be encountered any time northward of the 48th parallel, but this 

 is common knowledge to shipmasters sailing in higher latitudes; 

 so, for practical purposes, the surface ice patrol was conducted in 

 an area southward of the 48th parallel but northward of latitude 

 40°30'N. and between longitudes 43° and 54°W. 



U S. Coast Guard Cutter TAMPA 



TECHNIQUES OF ICE DETECTION 



Icebergs present no particular problem when they can be detected 

 in time. However, throughout the ice season the Grand Banks area 

 experiences some of the poorest visibility in the world. Detecting 

 and forecasting the drift of icebergs during extended periods of fog 

 has been a continuing problem for the Ice Patrol. Formerly, during 

 periods of reduced visibility, patrol cutters would stop their engines 

 and drift with the current in the vicinity of the icebergs they were 

 guarding. Often the patrol would lie-to at night as it was impossible 

 to search out bergs in the darkness. 



Under excellent conditions a large berg may be sighted at a 

 distance of about 18 miles, but with a hazy horizon this distance can 

 be reduced to less than 10 miles, and in a light fog or drizzling rain the 



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