Devastating 'Dust Bowl' Explained
"Previous research had demonstrated a link between some droughts and peculiar patterns of sea surface temperatures in different parts of the world. Schubert and his colleagues used a computer climate model to analyze conditions during the past 100 years. They found that ocean temperatures, particularly in the tropics, heavily influenced the dry conditions experienced in North America. In the early 1930s, the waters of the tropical Pacific were cooler than normal, and those of the tropical Atlantic were warmer than normal."
Thanks to Chris Steins