I observed many other peculiar effects of refraction. Such phenomena are frequent on the commencement or approach of easterly winds, and are probably occasioned by the commixture, near the surface of the land or sea, of two streams of air of different temperatures, so as to occasion an irregular deposition of imperfectly condensed vapour, which, when passing the verge of the horizon, produced these appearances.
Parhelia, mock suns, and corona, haloes, are perhaps not so frequent in Greenland as in some parts of America. I do not recollect to have observed them more than thrice. In the first instance, I did not minutely notice the particulars. I recollect, however, there were two or three parhelia, and four or five coloured circles, some of which almost equalled in their colours the brilliancy of the rainbow. On the second occasion, several parhelia were succeeded by a lunar halo, together with the aurora borealis, and proved the harbingers of a tremendous tempest. The last phenomenon of the kind which I saw, consisted of a large circle of luminous whiteness, passing through the centre of the sun, in a direction nearly parallel with the horizon, intersected in various places with coloured circles of smaller dimensions.
Rainbows are common in these regions, but the fog-bow, or fog-circle, is more rarely observed, and is entitled to our attention. It is a circle depicted on the fog, which prevails in the Polar seas, at certain seasons, resting upon the surface of the water, and seldom reaching to a considerable height. On the 19th July, 1813, I observed one of about 30° diameter, with bands of vivid colours depicted on the fog. The centre of the circle was in a line drawn from the sun, through the point of vision, until it met the visible vapour in a situation exactly opposite to the sun. The lower part of the circle descended beneath my feet to the side of the ship, and although it could not be a hundred feet from the eye, it was perfect, and the colours distinct. The centre of the coloured circle was distinguished by my own shadow, the head of which, enveloped by a halo, was most conspicuously portrayed. I remained a long time contemplating the beautiful phenomenon before me.
In the phenomena of the winds, which I am now about to describe, I cannot be so precise as I have been in my observations on atmospheric temperature and pressure; being able to give a correct idea only of their peculiarities and direction, whilst their relative force, founded on conjecture, I am unable to express otherwise than in the phraseology of the mariner, which, it must be allowed, is somewhat ambiguous.
In proportion as we recede from the equator, we find the winds become more variable, irregular, and partial. Storms and calms, in the northern regions, repeatedly alternate, without warning or progression; forcible winds blow at one place, when, at the distance of a few leagues, gentle breezes prevail; a storm from the south, on one hand, exhausts its impetuosity upon the gentle breeze, blowing from off the ice on the other, without prevailing in the least; ships, within the circle of the horizon, may be seen enduring every variety of wind and weather at the same moment; come becalmed, and tossing about by the violence of the waves; some, under close-reefed topsails, labouring under the force of a storm; and others, flying under gentle breezes, from quarters as diverse as the cardinal points.
The most general preliminaries to sudden storms are perfect calms; curiously variable breezes, with strong squalls; singular agitation of the sea, together with thick snow, which often changes from flakes to powder, and falls in such profusion, as to occasion an astonishing gloominess and obscurity in the atmosphere. If the snow clear away, the gale is often at hand, whilst a luminousness on the horizon, resembling the ice-blink, sometimes points out its direction, and a noise in the upper regions of the air announces its immediate approach. In this variable and occasionally tempestuous climate, the value of the barometer is satisfactorily proved. My father once removed his ship from a most dangerous bight in the main ice, where she would probably have been lost, had she remained a few moments longer, in consequence of his having heard the rushing of a storm in the air, while at the mast-head. Before the ship was out of danger, a heavy gale commenced, but the sails being set, and the ship under command, she was extricated from the perilous situation. From this circumstance, he imagined that sudden storms frequently commence at some height in the atmosphere, and gradually descend to the surface. Intermitting gales are almost equally common with sudden storms, and variable winds prevail, in an extraordinary degree, in the frigid zone. The winds, indeed, among ice, are generally unsteady in their direction, and attended with strong gusts or squalls, particularly in very cold weather, and towards the termination of a storm. This variableness, being the effect of the unequal temperature of the ice and water, is curious, but the phenomenon that is most calculated to excite surprise is, that several distinct, and even opposite winds, with the force, in many instances, of a fresh gale, will occasionally prevail at the same moment of time, within the range of the horizon. The situation in which this circumstance occurs, would appear to be the point where conflicting winds contend for the superiority; and as, in some instances, their forces are effectually balanced, the winds, which simultaneously blow from the southward and northward, or from the eastward and westward, have their energies almost destroyed at the place of combination. Thus it sometimes happens that ships, within sight of each other, will, at the same period of time, experience every variety of weather, from calm to storm, from fair weather to thickest snow, together with several distinct and contrary currents of wind.
On the morning of the 30th of April, 1810, the ship Resolution—in which I served in the capacity of chief-mate, or harpooner—was, during thick showers of snow, sailing by the edge of a stream of ice, with the wind from the north-westward. About ten, A. M., the snow abated, and several ships were seen within the distance of three or four miles. As all of these ships were sailing “on a wind,” it was easy to ascertain the direction of the wind where they were, and curious to observe its variableness. Two ships, bearing north-east from us, had the wind at north-east; two, bearing east, had east or east-north-east; two, bearing south-east, had the wind at south-east; while, with us, it blew from the north-west. In each of these situations a fresh breeze prevailed; but in some situations, where there happened to be no ships, there appeared to be no wind at all. The clouds above us, at the time, we’re constantly changing their forms. Showers of snow were seen in various places at a distance.
Instances of local storms are not uncommon in temperate climates, but in the arctic regions they are frequent and striking. Their locality is such, that a calm may occur when a storm is expected and actually does prevail at a short distance, so that the indication of the barometer may appear to be erroneous. In such cases, however, the reality of the storm is often proved by the agitation of the sea. Swells from various quarters make their appearance, and frequently prevail at the same time. My father, whose opportunities of observation have been very numerous, relates the following instance of the locality of a storm. When commanding the ship Henrietta, he was on one occasion navigating the Greenland Sea during a tedious gale of wind, accompanied with snowy weather. As the wind began to abate, a ship appeared in sight, under all sails, and presently came up with the Henrietta. The master hailed, and inquired what had happened that my father’s ship was under close-reefed top-sail in such moderate weather. On being told that a storm had just subsided, he declared that he knew nothing of it; he observed, indeed, a swell, and noticed a black cloud a-head of his ship that seemed to advance before him until he was overshadowed with it a little while before he overtook the Henrietta, but he had had fine weather and light winds the whole day!
A single instance is given of those sudden gusts and various currents of wind, which occur at some elevation in the atmosphere, and which are common to all climates. On a particularly fine day, my father having landed on the northern part of Charles’s island, incited by the same curiosity which led him on shore, ascended, though not without great difficulty and fatigue, a considerable elevation, the summit of which was not broader than a common table, and which shelved on one side as steep as the roof of a house, and on the other formed a mural precipice. Engaged in admiring the extensive prospect from an eminence of about two thousand feet, he scarcely noticed the advance of a very small cloud. Its rapid approach and peculiar form (having somewhat the appearance of a hand) at length excited his attention, and when it reached the place where he was seated in a calm air, a torrent of wind assailed him with such violence, that he was obliged to throw himself on his body and stick his hands and feet in the snow to prevent himself from being hurled over the tremendous slope which threatened his instant destruction. The cloud having passed, the air, to his great satisfaction, became calm, when he immediately descended by sliding down the surface of snow, and in a few minutes reached the base of the mountain in safety.
The course of the seasons, as relates to prevailing winds, is as follows. In the spring months, north-east and east winds are frequent, with severe storms from these and other quarters. The storms from the north-east, east, and south-east, are generally the most violent. When they occur in March and April, they frequently continue without intermission for two or three successive days, and rarely subside till the wind veers round to the north or north-west. Storms, in the spring of the year, blowing from the south-east, generally change, before they abate, to the east, north-east, north, and north-west; but storms commencing at south-west or south, usually veer, before they subside, in the contrary direction, towards the north-west, and sometimes continue changing until their strength is spent in the north or north-east quarter. A storm beginning to blow from the western quarter seldom continues long; when it blows hard it commonly veers to the north or north-east, and it is observable that a very hard southerly or easterly gale is frequently succeeded within a few days by another from the opposite quarter. With the advance of the month of May, storms become less frequent, and the weather becomes sensibly better. The winds then begin to blow more frequently from the north-west; in June, the most common winds are north and north-west, south and south-west; and in July, south and south-westerly winds prevail. At this season, calms or very light winds also become frequent, and continue sometimes for several days together. In high northern latitudes, however, very heavy storms from the southward occur in July, and blow for thirty or forty hours at a time. In August, north-east winds begin again to prevail. The south-west and southerly storms of the autumn blow with particular violence. “The wind rages so vehemently, that the houses quiver and crack, the tents and lighter boats fly up in the air, and the sea-water scatters about in the land like snow-dust—nay, the Greenlanders say that the storm rends off stones a couple of pounds’ weight, and mounts them in the air. In summer, whirlwinds also spring up, that draw up the waters out of the sea, and turn a boat round several times.”