Lake-Effect Snow | 06 Dec 2024

Source: IE 

Why in News?  

Recently, parts of upstate New York, Pennsylvania, Ohio, and Michigan, situated along the Great Lakes of North America, witnessed "lake-effect snow."  

  • A heavy snowstorm caused by this phenomenon near Lake Erie in New York has transformed homes into ice-covered igloos. 

What is Lake-Effect Snow? 

  • Definition: Lake-effect snow is a localized weather phenomenon characterized by heavy snowfall that occurs near large bodies of water, such as the Great Lakes in North America.  
    • It typically happens during colder months when cold air passes over relatively warmer lake surfaces, resulting in intense and narrow bands of snowfall. 
  • Mechanism of Formation: 
    • Cold Air Movement: Cold air often from Canada, flows over the unfrozen, warmer waters of the Great Lakes in North America.  
    • The lakes transfer heat and moisture to the cold air at the surface. 
    • Cloud Formation: The warm, moist air rises, cools rapidly in the colder atmosphere above, and condenses to form clouds. 
    • Snowfall: These clouds develop into narrow bands that produce intense snowfall, often at rates of 2–3 inches or more per hour. 

 Lake_Effect_Snow

Great Lakes of North America 

  • The Great Lakes, consisting of Superior, Michigan, Huron, Erie, and Ontario (from west to east), are among the most significant freshwater ecosystems in the world. 
  • Geography and Scope: The Great Lakes basin encompasses large parts of two nations, the United States and Canada. Except for Lake Michigan, the Great Lakes form a natural border between Canada and the United States. 
    • The lakes connect to the Atlantic Ocean via the Saint Lawrence River, and to the Mississippi River basin through the Illinois Waterway.  
  • Global Significance: The American Great Lakes account for 21% of the Earth's surface freshwater.