For the past three years, balloon pilots in the southwestern and western states have experienced some weird weather patterns that have cut flying time by as much as 40%. What is causing this weird weather? The most common answer has been "El Niño." Most people have heard about El Niño, but few know what it is. Do we know why it affects our sport of ballooning? Do we know how it is affecting weather patterns throughout the world? Do we care?
As the owner and operator of a full time hot air balloon ride business, I finally got curious enough to find out why my flights (read "cash flow") have dwindled over the past three years. I have log books going back to my first flight in 1980. My log books show up to 200 hours in some years. However, they also show a decline of 30-40% in logged hours over the past three years. It was El Niño!
What is El Niño? The full scientific name of the phenomenon is El Ni–o Southern Oscillation (ENSO). Under normal conditions, the trade winds blow from east to west across the Pacific. These winds push the warm surface water toward the Philippines, which allows cool water to rise up from the ocean depths off the coast of South America. Every few years the trade winds collapse and the warm water moves back to the east as a vast, slow wave that covers up the supply of cold water. The cycle usually occurs in a three to seven year pattern and the rise in sea surface temperature is 5 to 7 degrees Fahrenheit. Because it frequently occurs around Christmas, it was named El Niño, the Little One, in reference to the infant Jesus. Over the past 15 to 20 years, science has discovered just how inappropriate the name is.
How does El Niño affect the world? The first negative effect discovered was the destruction of the fish population and commercial fishing operations off the western coast of South America. In normal years, the cool water rising from the ocean depths brings up nutrients that support the fish population. When the warm water moves back to the east, stopping the rise of cool water, the fish die off, crushing commercial fishing in the area. It is now known that El Niño affects weather patterns worldwide, causing droughts in Indonesia and floods in California. The resulting effect on crop harvests around the world is devastating to the world food supply.
The Pacific Ocean has a current known as Kurishio, similar to the Gulf Stream in the Atlantic. El Niño has been strong enough to push this current about 200 miles north of its normal path, further affecting weather patterns. Scientists at the Naval Research laboratory at the Stennis Space Center in Mississippi have tracked the El Niño wave moving from west to east by satellite. Measuring only eight inches high and moving about five miles per hour, the wave is not something you would notice from a ship. They tracked it for two months as it moved eastward across the Pacific and spread along the coast. Sea levels as far away as Alaska rose and warmed, then, like any other wave, it receded slowly back across the Pacific.
El Niño causes a domino effect that shifts weather patterns, wind and rainfall worldwide. The pool of warm water has spawned atmospheric convection in the central Pacific, which injects moisture into the atmosphere. This moisture, now in the subtropical jet stream, carries winter rainstorms from the Pacific Ocean onto the coast of California. Continuing across the southern tier of the United States, the subtropical jet stream carries the moisture and these storms into the Gulf Coast states, where it then helps pump abnormally warm air into the Northeast. While the United States experiences increased rainfall, other parts of the world, including the east coast of Africa, the Philippines and northern Australia, experience drought.
What causes El Niño? Scientists and researchers vary in their beliefs concerning the cause. They have a standard reply to questions like this: it is the nature of weather for wild fluctuations to occur. Their proof: there is a record broken every day (heat, cold, rain, drought) somewhere in the world. Is it global warming? Is it global cooling? Is it the declining ozone layer? Was it the eruption of Mount Pinatubo in the Philippines four years ago? All of these are suspect. However, no reputable scientist will say it was any of these.
Weather prediction is, at best, a crap shoot. Meteorologists, with their satellites and supercomputers, have become very good at forecasting the weather for five to ten days in advance. However, offering definitive explanations for long-range atmospheric complexities is something no scientist can do. The world's weather is a prime example of the phenomenon of chaos. It is a cause-and-effect system so devilishly complex that it becomes inherently unpredictable. What causes El Niño? There are many theories, but no answers at this time.
How long will El Niño last? This is the hard one. No one knows! Normally, El Ni–o occurs only once every three to seven years and lasts only one year. The strongest El Niño this century lasted twelve years. The El Niño we are now experiencing has been with us for three years and is now forecast to last through 1995. Some meteorologists reported seeing signs of a developing El Niño as early as 1989. The real warming, however, did not begin until late 1991, reaching full force in 1992. Note that this occurred over the Christmas season. It played a role in North America's mild winter and contributed to a severe drought that plagued southeast Africa.
In the middle of the last two years a drop in sea surface temperatures in the central Pacific appeared to indicate the end of this El Niño. These weakening El Ni–o conditions continued throughout the year, but then unexpectedly gained strength again in December. Because of the worldwide implications, researchers are now investigating this weather phenomenon in depth. From their observance of the wave moving to the east they can now more effectively predict the effects of El Niño on the weather patterns for the coming year and forecast harvests around the world. What they haven't been able to do is to forecast the wave itself.
Mike Rose is a member of the Plano Ballooning Association and operates a commercial ride business. He researched El Niño to quench his own curiosity about the weather that has kept him out of the sky. Resources for this article include Discover Magazine, The New York Times, Science Magazine, Science Digest, Science News and Canadian Geographic.
