Icebergs and the Weather
The intimate relation existing between the Climates of particular seasons, and the discharge of Icebergs from the great Arctic glaciers has long been perfectly understood and described by both British and American naval officers. But the quantity of ice annually released in the shape of bergs is so insignificant, majestic as those frozen masses are, in proportion to the quantity remaining behind, and to that annually engendered over the vast area of the Arctic continental icefields, that any difference in the amount of “average” annual discharge cannot materially disturb the balance. Nor is the disengagement of the bergs, when viewed on a large scale, a process depending on variable conditions. The slow downward descent of glaciers towards the ocean (which is now fully recognised as the result of a well-known law) is dependent on forces of such vast magnitude and in such constant operation as to admit of no perceptible modification owing to local atmospheric influences.
What does materially affect climate, however, is the variation in the annual range, Equator-wards, of the great Arctic currents, which convey on their surface not only the bergs, but the vast compact fields of pack-ice, extending over areas of many thousands of square miles, and thus bringing about a reduction of temperature, infinitely in excess of that produced by the bergs.
The exceptionally boisterous and rainy summer of 1860 was due to the much increased southward range, along the eastern and southern shores of Greenland, of the Spitzbergen drift, and was alluded to by Dr. Wallich, in some observations published by him at the close of that year.