The sky is almost smothered by the black churning of an immense cloud, and the vast extent of the sea begins to agitate heavily. . . . Certain kinds of artists find the upheaval of the ocean, its rages and cataclysms, utterly compelling. Emil Nolde -- Northern Romantic if ever there was one -- produced some of the twentieth century's most dramatic paintings of the sea's turmoil. The thunderous, looming accumulations of oil and pigment in his pictures, the glaring colours, the head-on clashes of cosmic light and dark: all these amount to something more than a record. They come nearer to an identification with the subject -- not as merely seen but as involved experience. The surface of the picture almost becomes the sea; the viewer does not so much look at it as becomes a part of it.
Throughout his life, Nolde continually returned to his fascination with the great rolling deep, always confronting its awe with the same confident familiarity and lack of hesitation. As in ''The Sea B'' of 1930 (one of a series identified alphabetically), he rediscovered the ocean as a kind of surging, molten landscape, not as an image of frenzied chaos or a shattering of insubstantial vapours, but as the solid shaping of elemental forces, large and surprisingly simple. The ocean's great hills and valleys lift gigantically to fall. An entirety heaves. And his paint, in spite of a freedom and liquidity so similar to the sea itself, masses all this overwhelming movement into a primal grandeur.
Nolde once described the act of painting as being carried away by a storm of the imagination more real to him than the scene he was depicting. Writers tend to emphasize the instinctive, spontaneous nature of his art, its hallucinatory quality, and the way he let the paint suggest images as he worked. The artist Paul Klee summed him up as ''Nolde, the primeval soul.'' But on the other hand, nobody could paint the essential sea with the potency of Nolde unless he was intimately aware of its behaviour and able objectively to analyse it. Impulse may be the driving force, but a deliberate and conscious knowledge can hardly be denied.
The fact is that Nolde lived most of his long life in northern Germany, within sight and sound of the sea. He must have been as aware as any other artist of the ocean's ubiquity, and he also spent long periods on islands in the North Sea. This particular painting was made while he stayed on the Island of Sylt. On one occasion, early in his career, he was sailing home in a small cutter from an island in the Kattegat when a furious sea tossed the boat so violently that he never forgot the experience, not for its horror but as a stimulus for his art. Years afterwards, he wrote that he ''painted seas with wildly rolling green waves, and only a tiny bit of yellow sky at the upper corners.'' He rather melodramatically wondered ''if a wave, breaking over the deck, had swept me overboard, and if I had to fight for my life against the element, would I have been able to paint the sea even more powerfully?''
The same sort of intimate acquaintance with the sea is to be found in the work of the English nineteenth-century painter Turner, who is supposed to have had himself lashed to a ship's mast in a terrible storm so as to subject himself totally (but safely) to its ferocity. Like Nolde, he combined observation (stored in a remarkably visual memory) with an almost literal immersion in the feel and excitement of the sea.
The sea has appealed productively to many Romantic artists, and astonishingly similar paintings of its turbulence have come from the hands of such apparently different painters as Albert Pinkham Ryder, Gericault and Jackson Pollock, as well as Turner and Nolde. Nolde may well have believed himself prompted by his own isolation and by his closeness to nature, but he was also -- how unconsciously is not clear -- working squarely in the tradition of Romantic art and (in the case of the sea paintings) in its transmutation of storms into the controlled exhilaration of art.