Above and below them are belts called the “Variables” before bands of prevailing westerlies (called the “Roaring Forties” in the Southern Hemisphere) occur between about 40 and 60 degrees. | Above and below them are belts called the “Variables” before bands of prevailing westerlies (called the “Roaring Forties” in the Southern Hemisphere) occur between about 40 and 60 degrees. |