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Tides.—The mean rise and fall in Port Clarence is about 1 foot (0.3 m). Southwesterly winds increase and northeasterly winds decrease the height of tide.
Current.-Outside of Point Spencer the current set northwestward with a velocity of 1 to 2 knots.
Directions, Port Clarence.—In approaching Port Clarence in thick or misty weather the long, low spit of sand and shingle which forms the west side of the bay is not seen until close-to. The best course from Nome or points south is to make King Island, keeping in depths greater than 10 fathoms (18.3 m) to avoid the foul ground northward from Sledge Island, and obtain a good position before proceeding farther. From King Island, a course may be set a little eastward of Cape York. The north westward set of the current in this region should be kept in mind. After making Cape York, the coast may be followed eastward to the entrance to Port Clarence, from which a course can be set to the anchorage just inside Point Spencer.
12. ARCTIC OCEAN
The remarks on the navigation of Bering Sea (p. 380) apply generally to the Arctic Ocean as far as Point Barrow, except that the current and depths in the Arctic are more uniform, and with the exception of the shoals at Cape Prince of Wales, Hotham Inlet, Blossom Shoals, and Point Franklin there are no outlying dangers, and the lead is an excellent guide in approaching the land. Another exception is that in the Arctic the question of ice must always be considered. The following remarks on the navigation, weather, and currents of the Arctic Ocean, by Capt. M. A. Healy, R. C. S., contained in the report of the cruise of the revenue steamer Corwin in the Arctic Ocean, 1884, though relating to an extreme season, may be of interest to those navigating these waters:
In my previous experience in the Arctic I have never seen a season like the past. From the time of first reaching the ice up to leaving the Arctic, dense fog has been almost constant. Currents that have hitherto been considered permanent in direction, if not in force, have become erratic, and others have entirely failed. The ice fell back before the sun's advance slowly and compactly. For three weeks after we reached the Diomede Islands it refused entrance into Kotzebue Sound, and three weeks later still it was hanging with discouraging tenacity around Point Hope. It was unsafe to anchor with any but a short scope; moving steam had to be kept; and constant vigilance exercised to prevent being dragged ashore by fields of ice moving in the rapid and changing currents. For weeks at a time it was impossible to take observations, dead reckoning was almost worthless, owing to the continual changes in force and direction of the currents, and the safety of the ship depended entirely on the constant use of the lead. Fortunately for those who are obliged to sail this frozen ocean the depth of water is not so great but what bottom can always be obtained, and the proximity of land is indicated by regular shoaling, with but few exceptions. Yet with this aid and the best charts that we have, several years' experience is necessary to enable the navigator to judge with any degree of precision the position of the ship. Anyone at all familiar with coasting knows how difficult it is to recognize land in a fog, where marks are well defined-high bluffs often appearing like low beaches and small rocks looming to gigantic size, while the general contour of the small portion of the shore visible may be taken for almost any land that one expects to make. How much more difficult must it be where the formation of the shore for miles differs but little, as is the case in the Arctic.
Among the best landmarks that we have in these northern waters are the bird rookeries at King Island, the Diomedes, Cape Seppings, Cape Thompson, and Cape Lisburne. The distance between these rookeries enables one to form a very accurate idea of the one he is approaching, while the cries of birds congregated at them answer the purpose of a fog signal. With one or two exceptions these are the only aids to navigation.
In the shallow waters of this ocean the effect of the wind on the currents is very marked.
Inside the Arctic Circle snow has fallen all the past season, and it may almost be said that there has been no summer. As late as August 27 ice was within a few miles of Cape Sabine, and at the Seahorse Islands it was heavy and dangerous. The pack at this time was still southward of Point Barrow, and vessels could not go eastward of that place this season. During the latter part of our stay the weather was exceptionally severe.
The experience of many years in the Arctic has demonstrated the fact that no rules whatever can be given as to the time of the breaking up of the ice. The severity of the winter, the time at which spring weather opens, and the beginning of southerly winds that break up the ice all have their influence in governing this time. Vessels have been able to enter St. Michael as early as May 21; this year we found ice to the southward of St. Matthew Island on June 2, and some days later still in the season vessels have been stopped by it between the Seal Islands and Nunivak. The southern limit of the ice is almost entirely dependent on the severity of the winter. Heavy southerly winds and swell will break up the ice; and if followed by northerly winds it will open out and the waters become navigable. When once broken up, if the weather is mild, it will not cement again if nipping, and consequently will open more readily to light winds. Northeast winds tend to drive the ice off the American shore and westerly winds off the Siberian side. With these few exceptions, little can be said of ice conditions.
In clear weather the ice blink indicates the presence of ice, and it may be seen a great distance; but in thick, foggy weather approach to the pack must be made with great caution. Its proximity is usually indicated by the slack, and when this once begins to be seen about the vessel it may be judged that a large body is not far distant. As the pack is neared, one sees only ice as far as the eye can reach. It rises from 10 to 25 feet above the water. It is a well-known fact that the depth of water and the surrounding features of this ocean render the formation of large icebergs an impossibility.
When a pack is reached, it usually becomes necessary to track along its edge to find a lead. Whoever is piloting the ship takes his place at the masthead and with glass in hand seeks for a favorable opening. Oftentimes days are spent working up and down along the ice without clear water presenting itself, and when it does extreme caution must be used in entering the lead. It is here that the judgment and experience of the ice pilot becomes a necessity. The weather, currents, appearance of the ice, probable winds, and a dozen other things that would never enter the mind of a novice are to be taken into consideration before the vessel's head is turned into the pack. Once it is determined to enter the lead, vigilance must be doubled and every faculty kept on the alert. The vessel is conned from the masthead, and, while directing how the helm must be put to keep clear of immediate danger, the pilot must be looking ahead for the clearest water and watching ice, sea, and sky for change of currents and winds. If any signs of the closing-in of the lead are presented, the vessel must be gotten out as soon as possible, for, if shut in and she escapes being crushed, she will go to the northward in the drifting pack from 1 to 2 knots per hour, and it will become necessary to abandon her. If the lead followed up is between the ground ice and the pack and the wind comes onshore, a safe place can sometimes be found behind the ground ice. A vessel may be made fast to this ice with grapples, or anchored to leeward of it, and lay with comparative safety. If anchored in a current, however, with drifting ice about her, the scope of chain must be short and everything kept in readiness for getting under way at a moment's notice. If anchored in shoal water, it is desirable to get in the ice as far as possible to avoid the swell; but if the water is deep, the ice should be avoided. Generally the presence of the ice tends to kill the swell, and it will be found much smoother inside the ice than out.
The bowhead whale keeps as far to the northward as he can find spouting holes, and to take him the whalers are obliged to keep as close to the pack as possible. Usually they track along the Asiatic side in Bering Sea and Strait, and, as they reach the Arctic, cross over and work up the American shore to the northward and eastward. In Bering Sea there is very little danger in entering the ice, as it is almost sure to open and offer a chance to escape before reaching the Arctic. With a knowledge of this fact, whalers sometimes enter the ice to the southward of the strait and endeavor to work through it if they have reason to believe, from the sudden disappearance of the whale, that there is clear water to the northward. In the Arctic, however, the pack is carefully avoided, and it is only when conditions are most favorable that attempts are made to follow up the leads. Point Barrow is approached with the greatest caution, as it is one of the most dangerous places in the Arctic. As has already been mentioned, by far the major portion of the vessels lost in the Arctic are wrecked in its vicinity.
Ice.—Bering. Strait is free of ice by the first week in July and sometimes earlier, but clear water does not extend very far northward, and it is seldom possible for vessels not fitted to encounter ice
to reach Point Hope before July 10–15. Kotzebue Sound is usually open by July 15, at times a few days earlier, but it has been known to remain closed until the last of July. The running ice from Kotzebue Sound is encountered at Point Hope some time after the pack has moved northward. By July 15 the main pack has moved north of Cape Lisburne.
Thús far the movement of the ice does not appear to depend to such a great extent on the winds, it is reasonably certain each year, and dates can be depended upon within a small limit of time; but north of Cape Lisburne the movement is generally slow, uncertain, varying greatly in point of time in different years, and seems to depend almost wholly on the winds for its further movement. Prevailing northeasterly winds move it away from the shore rapidly and early, while southwesterly or westerly winds hold it against the shore and make a late season.
From Icy Cape north no specific time can be set for the opening of navigation. Its variations are from July 12 to the latter part of August, though an average date for the whaling vessels to reach Point Barrow is about August 1. Between these points and the early part of the season the ice is always dangerously near the shore, and southwesterly or westerly winds will bring it in. Later, the southern point of the pack is just off Seahorse Islands and generally remains there the rest of the season. From the Seahorse Islands to Point Barrow the pack is seldom far offshore, and from the latter point can almost always be seen. During the open season it is always liable to come in on these two points with a westerly wind.
Beyond Icy Cape there is always danger to vessels, and strangers should be cautious and careful in going there. In the lead of open water between the pack and the shore the current is swift and nearly always carries drift ice, and vessels rarely reach Point Barrow at any time without encountering some ice. The ice cannot be forced, and vessels should not venture into small leads between the pack and shore ice. With a southwesterly or westerly wind, which brings the ice in, vessels seek protection east of Point Barrow when it is open, in Peard Bay close in as possible, and under the lee of heavy ground ice, which acts as a breakwater against the smaller cakes. In anchoring where there is drifting ice, vessels should use a short scope and be ready to get under way immediately. A comparatively small cake will sometimes cause the loss of an anchor and chain. In the vicinity of Point Barrow sailing vessels should not go offshore in water too deep to anchor, as in light winds or calms the current is likely to take them into the pack. Navigation east of Point Barrow is such that it should only be attempted by those having experience.
As a rule, the pack does not come down on Point Barrow before the latter part of September, but in 1897 it came down the first of September, and, in general, except for whaling vessels, whose officers are men of long experience in judging the ice, weather, etc., September 1 is as late a date as vessels should remain in that vicinity. About this time, or a little later, young ice begins to make in the lagoons, along the shore, and around the old ice, though it is not likely to form in the open sea until the last of the month. The young ice makes stronger and spreads over the open sea with the advancing season. It is dangerous to vessels, and will very quickly cut through
one not sheathed to withstand it. Ordinary vessels should be out of Kotzebue Sound by September 15 to 20, and out of the Arctic by October 1. The whaling vessels made it a rule to be ready to leave there about October 10, and though there were times when they stayed later, these were exceptions.
At times there is a body of ice, which holds on the Siberian shore through the summer, that moves down past East Cape into the western side of Bering Strait, sometimes as early as the latter part of August, and makes that side of the strait difficult of navigation late in the season.
Weather.-In summer the weather is usually light, with much fog and rain. The winds are variable, though mostly easterly and southerly. There are seldom gales in summer, but occasionally, sometimes with intervals of years, there come southwesterly gales, short-lived but very severe and disastrous, as there is little protection from winds in that quarter. In the vicinity of the ice the weather is nearly always light and foggy. Later in the season it grows more boisterous, gales are frequent and more generally from northward, and as the weather grows colder there is considerable snow.
Currents.-From Bering Strait to Point Barrow there is a general current setting northward alongshore (stronger inshore), which when not affected by winds or stopped by the ice, has a velocity of not less than 1 knot at any part of it. The current from the strait turns northeastward and is joined north of Cape Krusenstern by that from Kotzebue Sound. From Eschscholtz Bay a northerly current sets alongshore on the eastern side of Kotzebue Sound, having a velocity of 12 to 1 knot at Cape Blossom. It continues past Cape Krusenstern, where it is increased by the flow from Hotham Inlet to a velocity of 1 to 2 knots, and northward of the cape joins the current from Bering Strait, where, in the latter part of July and August, its velocity is 112 to 2 knots. It continues with the same velocity around Point Hope, then with a reduced velocity to Cape Lisburne and across to a short distance south of Point Lay. After rounding Point Hope, and thence to Icy Cape, the current does not appear so strong, and, as a rule, is about i knot.
In the bight between Cape Lisburne and Cape Beaufort there is a tidal current, and unless driven in by a westerly wind the outside general current is not felt.
Northward of Point Lay, if the ice has not opened up from the shore, the current is stopped; but if the ice is open to Point Barrow, the current continues along the shore and, because of the contracted space between the shore and the ice, increases in velocity to form 2 to 3 knots and sometimes more at Point Barrow.
This general current is more or less affected by the wind and may be decreased or even stopped at times by northerly winds, but when the wind abates it starts again. When the wind is with the current its velocity is increased. Well offshore the currents are variable and not so strong and depend to a great extent on the winds. There is however, a general set northward.
A report from the Coast Guard states that in the vicinity of Point Barrow (that is, from Seahorse Island to Point Barrow) a northeast wind will act against a northerly current and produce a resultant current which will carry the ice offshore.