hurricane Fran off the coast of the Bahamas during a non EL Nino year.

An El Niño Hurricane Slayer

Here we go again.  Here comes hurricane season.  That time of year when people start looking forward to summer vacations and others start watching the waters around the United States.   This week is the start of hurricane season in the United States and the beginning of insurance companies beginning to pray for peace and quiet.

The local meteorologists are talking about it, and the major networks are praising their colorful charts with numbers showing where they think we will stand when the season ends. Some will say
that Colorado State has a prediction of 13 named storms but because of this or that we think more or we think less. So who is right and who is wrong?  There have been quiet years like 2014 when we only had 9 named storms.   Then we have crazy years like 2005 when we had 28 named storms or 2012 where we had 19.  It seems as if mother nature has a mental disorder when it comes to hurricane season.  Now we are hearing the beginning chatter about another factor called an El Niño.

Peace and Tranquility? Someone get me an El Niño stat.

An El Niño is when the waters of the eastern central Pacific close to the Equator warm at least 0.5 degrees Celsius or more.  It is the difference between a cool bath and a warm bath.  The term El Niño comes from South American fisherman that noticed the warm up of coastal waters that occurred every so often around Christmas.  They referred to the warming as “El Niño,” (niño being Spanish for a boy child) in connection with the religious holiday.  An El Niño will usually last 9 to 12 months.

The twoGraphic showing rising air and descending air that will keep hurricanes from forming during an El Niño components of an El Niño are the sea surface temperatures and the atmospheric pressure.  The ocean and atmosphere work loosely together in a conveyor belt type relationship.  Think of moving sidewalks in an airport.  During an El Niño event, trade winds in the central and western equatorial Pacific weaken allowing the waters to warm.  The warm air from the water rises, causing the atmosphere above it to become more buoyant.  The changes in pressure cause the trade winds to become weak.  Warm air rises and is carried toward the Gulf of Mexico and the Caribbean.  As it rises and moves east it cools and begins to sink back to the surface.  El Nino causes more wind sheer and stable air over the Atlantic basin.  This sinking motion keeps tropical storms and hurricanes from being able to form in the Gulf of Mexico or the Atlantic basin. The trade winds push the top of the water west and cooler water from below replaces it.  This, in turn, causes the water to warm even more creating a cycle.  The absence of strong trade winds keeps the cooler water below from getting to the surface.

The Effects

There are many other effects that are felt around the world.  We will see above normal rainfall in the southern United States and in countries such as Peru and Ecuador.  An El Niño was not due back this soon.  Satellite imagery has indicated the warm waters returning and with that, we have a 50 percent chance of seeing the hurricane slayer’s return this summer.  With people planning trips and insurers licking their wounds from spring storm damage, that is good news.  Just remember that even though the east coast will see fewer storms the eastern Pacific will see more.  Look out, Cabo San Lucas, Mexico.

Print Friendly, PDF & Email