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UNITED STATES COAST PILOT

ALASKA-PART II—YAKUTAT BAY TO ARCTIC

OCEAN

The courses and bearings given in degrees are true reading
clockwise from 0° at north to 359°, and in a few cases are followed
by the corresponding magnetic course in points, in parentheses.
General directions, such as northeastward, west-southwestward,
etc., are magnetic, unless otherwise stated.

Distances are in nautical miles and may be converted approxi-
mately to statute miles by adding 15 percent to the distances
given.

Currents are expressed in knots, which are nautical miles per hour.

Except where otherwise stated, all depths are at mean lower low water. This plane of reference (p. - ) is abbreviated: m. l. 1. w.

In accordance with the desire of the International Hydrographic Bureau, each depth is followed in parentheses by its equivalent in meters.

Heights are given in feet with metric equivalent in parentheses.

Use this Coast Pilot with reference to the latest supplement that may have been published and the Notices to Mariners issued after the date of the edition of this pilot or of the Supplement.

1. GENERAL INFORMATION

THE COAST.—The information contained in this volume relates to the coast waters from Yakutat Bay to the Arctic Ocean, including the various groups of islands along the south side of the Alaska Peninsula, the Aleutian Islands, Prince William Sound, Cook Inlet, Bristol Ray, and the various other indentations.

Between Yakutat Bay and Cape St. Elias, the coast is fairly regular, being formed by river and glacier deposit. The great Malaspina Glacier borders a section of this coast.

From Cape St. Elias to Cook Inlet the characteristic formation is generally rocky; the waters in general are deep, but there are also great variations in depth. The visible topographic features, characterized by mountainous areas, numerous rugged islands, rocks, and reefs, are undoubtedly duplicated beneath the surface of the water. A safe rule to follow in the navigation of these waters is to avoid all areas where the chart shows great irregularities in depth.

In Cook Inlet the characteristic formation is the result of glacial action. At low water the shores will be seen strewn with boulders, some of them of great size, and the soundings indicate that these boulders also occur in the deeper waters, particularly in areas of hard bottom, where they have not been buried by the subsequent deposit of silt.

Westward from Cook Inlet, along the south side of the Alaska Peninsula, throughout the off-lying islands, and throughout the entire extent of the Aleutian Islands, the rocky formation above described is again found.

Bering Sea is characterized in general by shoal waters, with extensive sand or mud flats along the shores, particularly in the approaches to the various bays and rivers. There is little rocky formation, and its occurrence, where found, is limited in area.

Coast landings. There are many bold and precipitous sections of the open coast of Alaska that are inaccessible. A surf boat should be used in making landings on stretches of sand beach. On a rocky shore, the locality selected for landing should be free from nearby breakers and back of some rock or small point if available, but a small area partially enclosed and subject to violent to-and-fro movement of the sea should, of course, be avoided. The best landing place is one having a fairly steep-to face where covered and uncovered by the swell and at the same time offering adequate foothold. The swell here has less tendency to break or may not break at all.

The boat used for landings on a rocky shore should be moderately light so that it can be readily handled, and it should be of the square stern type. Approach is made stern-first under control of oars and having a line from the bow to an anchor some distance offshore if practicable. The line is manned so that the boat may be hauled away quickly at any time. The stern is brought within jumping or stepping distance of the selected spot immediately following the end of a break and a landing is made preceding the approach of the next break if there is time to do so. Several attempts may be necessary before a quiet spell of sufficient duration occurs.

Ice will seldom be encountered south of Unimak Pass. It occurs locally where discharged from glaciers, and in winter is formed at the head of the various inlets, but never gets far from its source. Its occurrence, and also the ice in Bering Sea, are discussed in detail under the headings of the various localities.

All ports in Alaska except those in Bering Sea and at the upper end of Cook Inlet, are ice free and open to navigation the year around.

Kelp grows on nearly every danger having a rocky bottom and will be seen on the surface of the water during the summer and autumn months; during the winter and spring it is not always to be seen, especially where it is exposed to a heavy sea. Kelp should always be considered a sign of danger, and no vessel should pass through it unless it is known that extensive sounding or a wire drag survey have definitely determined that no dangers exist. There are, however, many rocks not marked by it. Boulder patches are generally not marked by kelp. A heavy sea will occasionally tear the kelp away from rocks, and a moderate current will ride it under water so that it will not be seen. It is well to note that dead, detached kelp floats on the water in masses, while live kelp attached to rocks streams away level with the surface.

[blocks in formation]

Tide rips and swirls in regions of strong currents are usually encountered in the vicinity of shoals or islands and points of land, and they are therefore generally a positive indication of danger. The backwash of seas striking steep cliffs of a bold coast may often be felt at a considerable distance to seaward. Any change in the feel of the vessel proceeding in thick weather should be considered as an indication of danger near at hand.

Weather.- The weather in general is misty or rainy, with frequent blows. From April to October, mist and fog are prevalent. În the winter season and late spring northwest blows with clear weather are frequent. During the summer season the prevailing winds are mostly southeast to southwest with an occasional northeast storm. These summer storms are usually not very severe and are generally of short duration. As winter approaches the gales become more severe and prolonged.

A feature of Alaska weather is the williwaw, a violent gust of wind that sweeps down off the mountain slopes with great force. In stormy weather these williwaws will be experienced in coasting along the land, and in practically every harbor in western Alaska. Williwaws are dangerous to a vessel at anchor because of their very sudden occurrence and the radical changes in the directions of the successive gusts of wind. A vessel will yaw badly and is likely to break out her anchor. Sailing boats are liable to be capsized. A man cannot stand against a violent williwaw.

The weather is discussed in greater detail under the heading of the various localities. See also meteorological tables in the appendix.

TIDES.-Along the outer coast of Alaska between Yakutat Bay and the western end of Alaska Peninsula the tide is nearly simultaneous, high water occurring near the time of the transit of the moon. Between Yakutat Bay and Cape Whitshed. mean high water rises from 9 to 10 feet (2.7 to 3.0 m) above the plane of reference. Extreme variations from 4 feet (1.2 m) below to 15 feet (4.6 m) above the datum may occasionally be expected.

Throughout Prince William Sound the tide is practically the same in regard both to time and to height. High water occurs near the time of the transit of the moon, and the mean height of high water is about 11 feet (3.4 m) above the plane of reference. Extreme variations from 4 feet (1.2 m) below to 16 feet (4.9 m) above the datum may sometimes occur.

In Resurrection Bay the rise of tide is about 1 foot (0.3 m) less than in Prince William Sound.

In passing up Cook Inlet the time and height of the tide changes very rapidly. At Fire Island the tide is about 5 hours later than at Port Chatham. At Anchorage in Knik Arm it is about one-half hour later, and at Sunrise in Turnagain Arm about 1 hour later than at Fire Island. The height of mean high water above the plane of reference varies from about 13 feet (4.0 m) in the vicinity of Port Chatham to 30 feet (9.1 m) in Knik Arm and 33 feet (10.0 m) in the eastern part of Turnagain Arm. Variations from 6 feet (1.8 m) below the plane of reference to 6 feet (1.8 m) above mean high water may occasionally occur. The mean range of tide on the west side of Cook Inlet is less than it is on the east coast, the difference being as great as 3 feet (0.9 m) at the widest part of the inlet.

On the eastern side of Kodiak Island the height of mean high water is about 9 feet (2.7 m) above the plane of reference, but in Shelikof Strait the mean high water rises from 13 to 14 feet (4.0 to 4.3 m) above the datum. Extreme variations from 4 feet below to 14 feet above the datum on the eastern side and from 4 feet (1.2 m) below to 18 feet (5.5 m) above the datum on the western side of the island will occasionally occur. In Shelikof Strait the tide will occur about 15 minutes later than on the eastern side of the island.

From Kodiak Island to the westward the range of tide diminishes rapidly. In the vicinity of the Shumagin and Sanak Islands the mean high water is approximately 6 feet (1.8 m) above the plane of reference. There is, however, very little difference in the time of the tide until the western end of the Alaska Peninsula is reached.

Around the Aleutian Islands the tide is very irregular and at times becomes diurnal. The mean high-water interval varies from zero to 4 hours, and the mean rise of tide from 2 to 6 feet (0.6 to 1.8 m) above the datum.

At the Pribilof Islands, St. Matthew Island, and St. Lawrence Island, in the Bering Sea, the tide is small and irregular, the mean rise being less than 4 feet (1.2 m) above the datum.

In Bristol Bay the range of tide increases very rapidly in passing toward the head of the bay. At Port Moller the mean rise is 912 feet (2.9 m) above the datum, and at Clark Point, Nushagak Bay, it is 18 feet (5.5 m). At the latter place the tide occurs approximately 5 hours later than at Port Moller.

In Kuskokwim Bay the height of mean high water above the plane of reference increases from 7 feet (2.1 m) at Goodnews Bay entrance to 1012 feet (3.1 m) off Warehouse Creek and then diminishes to 21/2 feet (0.7 m) at Bethel. At Apokak the tide occurs nearly 4 hours later than at Goodnews Bay entrance, and at Bethel it is about 512 hours later than at Apokak. The range of tide is greater on the east side than it is on the west side of the bay, the difference being about 1 foot (0.3 m) in the vicinity of Apokak.

In Norton Sound the tide is generally small and irregular and during a large part of time diurnal. The mean rise and fall is about 3 feet (0.9 m).

In the vicinity of Bering Strait the tide is too small to be of practical importance.

Along the Bering Sea coast of Alaska extreme tides, varying from 3 feet (0.9 m) below the plane of reference to 6 feet (1.8 m) above mean high water, may occur occasionally.

Tide Tables.-For daily predictions of the tides in Alaska reference should be made to the Tide Tables, Pacific Ocean and Indian Ocean, published annually in advance by the Coast and Geodetic Survey; price 25 cents.

CURRENTS.-A prevailing current sets northward and westward along the coast of British Columbia and Alaska.The distance it extends offshore is not known, but it is believed to be strongest near the coast and inside of the 100-fathom curve.

The estimated velocity of the current is 0 to 112 knots, and is greatly affected by strong winds. In winter, with strong northerly and westerly winds prevailing in the Gulf of Alaska, it is probable that the current is stopped, and there may be a set in the reverse

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