Virginia National Guard helicopter rescuing an individual from the James River. Note: rescued man halfway up to helicopter. Helicopter crewman standing on debris in river. Courtesy NWS Collection.
“Fifteen years ago, storms battered the West Coast of the United States…There were droughts in Australia, Indonesia, and India…Worldwide, 2,000 people died…Economic losses amounted to billions of dollars…In Indonesia and Borneo, dry conditions fed raging forest fires that consumed hundreds of thousands of acres. Smoke blanketed the area..."
From the PBS news program, “Bracing for El Niño”
October 7, 1997
What caused these disasters? Just some warm water in the Pacific Ocean!
Every two to seven years, trade-winds in the Pacific Ocean slow down or reverse their direction (no one is sure why). Normally, the Pacific trade winds blow vigorously towards the west. This causes warm surface water to pile up in the western Pacific, so that the sea surface is actually about 1/2 meter higher at Indonesia than at Ecuador. These winds also cause sea surface temperatures to be about eight degrees Celcius higher in the west, with cool temperatures of South America, due to an upwelling of cold water from deeper levels. This cold water also brings up nutrients that support the growth of marine plants, which provide food for major fisheries.
But when the trade winds slow down, everything changes. Water temperatures become warmer in the eastern Pacific and colder in the west. Nutrient upwelling slows, and fish populations become much smaller along the Pacific coast of South America. Rainfall follows the warmer water, causing flooding in Peru and drought in Indonesia and Australia. Changes in the circulation of Earth’s atmosphere bring unusual weather to other regions that are far away from the tropical Pacific. Fishermen in South America noticed that these changes usually happen around Christmas time, and named the event “El Niño,” which means “the (Christ) Child.”
El Niño isn’t all bad; some of the changes it causes in atmospheric circulation can reduce the chances of severe hurricanes in the North Atlantic. But many other changes are highly destructive and dangerous, so advance warning of El Niño’s approach is extremely important for emergency preparation. NOAA satellites are constantly collecting information on sea surface temperatures around the globe. NOAA also operates a network of buoys that measure temperature, currents, and winds in the tropical Pacific Ocean. Every day, these buoys transmit data that are immediately available to researchers and forecasters around the world.
Here’s a way for you to create a miniature El Niño in your own kitchen!
Have an adult help with the hair dryer, and be careful with any electrical appliance around water! Follow warnings on the paint container label concerning ventilation and handling.
You can find out more about El Niño at:
This activity was adapted from “Make Your Own El Niño in the Classroom,” developed by Kelly Perry (NASA Jet Propulsion Laboratory), Johan Berlin (Raytheon Corporation), James Kendall (NASA Jet Propulsion Laboratory), and Ruby Krishnamurti (Florida State University) and was originally presented on NASA’s Jet Propulsion Laboratory Education Web page (https://www.jpl.nasa.gov/edu).