Comments In the Atlantic Ocean, Subtle Shifts Hint at Dramatic DangersSkip to Comments The comments section is closed. To submit a letter to the editor for publication, write to letters@nytimes.com. In the Atlantic Ocean, Subtle Shifts Hint at Dramatic Dangers March 2, 2021 445 The warming atmosphere is causing an arm of the powerful Gulf Stream to weaken, some scientists fear. In the Atlantic Ocean, Subtle Shifts Hint at Dramatic Dangers The warming atmosphere is causing an arm of the powerful Gulf Stream to weaken, some scientists fear. By The Gulf Stream has shaped climate and history on four continents. Currents swing west from Africa, ultimately influencing weather patterns from Caracas to Miami to Europe.