The hurricane
During the novel, Hurricane Carol, which struck the East Coast in 1954, is bearing down on Shutter Island. Lehane uses the image of the hurricane to create a wide variety of psychological effects to evoke the feeling of something ominous looming. In the eye of the hurricane, the weather is eerie, still, and charged. When it is raging, as when Teddy and Chuck are in the mausoleum and they witness a tree fly by them upside down, it evokes unchecked natural rage. The hurricane evokes a natural world of violence and malevolence.
Nuclear Annihilation
Many of the characters allude to the fear of being destroyed in nuclear war. Litchfield, the patient that Teddy and Chuck encounter in Ward C, gleefully describes the hydrogen bomb, which implodes on itself. Teddy recalls Dolores, in turn, having been made anxious by the news of the escalating arms race between American and Russia. The repeated mentions of nuclear annihilation suggest that the madness of Shutter Island is not limited to the island, but has gripped the world itself, and that at any moment everything could collapse or be destroyed. The repeated mentions of the atomic and hydrogen bomb create a claustrophobic feeling, as though there is no way out from the violence whose memories haunt Teddy.
The Ocean
The book begins with the image of Teddy on his father's fishing boat, overwhelmed by the vastness of the ocean. The image of the ocean—vast, unfathomable, insurmountable, filled with slimy, disgusting creatures—evokes a feeling of vertigo, weakness, and sickness that hangs over the entire novel. It ultimately stands in for Teddy (as well as Dolores's) relationship to the world itself, as something gigantic, overwhelming and inhuman.
Imprisonment
In virtually every scene the novel underscores just how heavily guarded Ashecliffe is. Lehane mentions bars, guards with batons, electric fencing and barbed wire, and the jagged cliffs that surround the island. To go anywhere on the island, Teddy and Chuck have to be escorted and pass through security. The imagery underscores the overwhelming desolation of the island, and the hopelessness of the patients there, contrasting sharply against the humanitarian mission that Dr. Cawley and Warden McPherson cheerfully describe.
Lobotomy
The transorbital lobotomy is mentioned again and again throughout the novel, though we never see the procedure performed, and never encounter a character who has been lobotomized. The procedure hangs over the entire novel as the ultimate punishment, a fate worse than death, effectively trapping the person who has undergone it in their own body, unable to act of or speak. The procedure is meant to be doubly horrifying because it is an act of wanton cruelty disguised as a scientific and even humanitarian act. Unlike the violence that Teddy is used to, it is icy, clinical, removed.
