Home Contact Register Subscribe to the Beacon Login

Wednesday, September 21, 2016

DENNIS PATRICK: IS IT JUST LA NINA TIME AGAIN

JIM’S TRUCKS

 

 

“Water, water everywhere but not a drop to drink.” So reads a line in Coleridge’s poem “The Rhyme of the Ancient Mariner.” The mariner who shot an albatross (a symbol of good fortune) brought misfortune to his ship and crew.

            A contemporary Chicken Little version might be, “Fossil fuels; man-made global warming.”

            Not so fast. What might be other rational explanations for climate variations?

            One well-established weather cycle is the El Nino - La Nina pattern.

The near-record 2015-2016 El Nino season brought devastating rains and dangerous flooding across the southern US. Typically, the flip side of the El Nino would be an equally harsh La Nina raging across the northern plains states the following year. At this point, however, with the Pacific Ocean cooling down, the odds of a near-record La Nina have dissolved. Columbia University's Earth Institute now indicate the probability of La Nina to be less than 50-50.

Since the end of the 2015-2016 El Nino season in April 2016 the tropical Pacific has remained pretty much in neutral. For now, at least, NOAA is taking down the La Nina watch. Forecasters think it will probably remain that way with conditions no longer favorable for La Nina to develop over the next six months.

If the probability of La Nina were higher, here is what might occur historically. We could expect a more active storm track with above normal precipitation and below normal temperatures. The storm track would extend from the Pacific Northwest across the northern plains into the northeast. The southern states would experience drier weather and much warmer temperatures during the 2017 winter and summer.

Without a doubt, Old Man Winter has us in his cross hairs. But, as it stands now, North Dakota should not experience an unusually wet or cold winter and spring.

The long-range meteorological forecast is based on substantive observations and not exclusively on ill-conceived computer model projections. The El Nino - La Nina cycle is a well-established weather pattern. This weather pattern occurs in the Pacific off the coast of South America, thus the Spanish names. La Nina means “Little Girl” and occurs as the opposite or reverse weather pattern of the El Nino. El Nino means “Christ Child” because the seasonal pattern begins around Christmas time.

For centuries South American fishermen recognized the fluctuation of warmer and cooler waters along the coast of Peru and Ecuador. Not until the 1920s did British meteorologist Sir Gilbert Walker identify and record the fluctuations. He theorized that the association between water temperatures and atmospheric conditions created cyclical weather patterns leading him to conclude what he dubbed the Southern Oscillation of El Nino - La Nina effect.

The La Nina portion of the cycle produces the volatile wet weather pattern we experienced in 2011 and 2012.

La Nina occurs when sea surface temperatures along the equator in the central and eastern Pacific fall below normal. Conversely, warmer sea surface temperature occur in the western Pacific. It is believed that La Nina results from the increased strength of the normal trade wind circulation. Typically, the trade winds drive warm Pacific surface water westward to the regions of Indonesia and Australia. This movement permits cooler water to well up along the South American coast. Why these winds increase in strength is not completely understood. The amount of cooler Pacific water moving toward South America reduces the air temperature and generates winds along the coast.

The effect on the northern hemisphere is the crux of the matter for the northern plains. Changes in the tropical Pacific, both in water temperature and in the trade wind circulation, induces wide fluctuation in the jet stream in the middle latitudes. This alters the course of the jet stream crossing the United States. Such a shift in the jet stream results in a wide variation in the strength and location of storms. In other words, radical changes in the atmosphere and jet stream cause radical variation in temperature and precipitation across North America. This alteration may last for several months, then subsides and reverses.

So much for the prognostications of man-made global warming. One might just as well believe in the misfortune brought about by shooting an albatross as believe in anthropogenic climate change. I prefer the science of the meteorological explanation of Southern Oscillation.

We can’t control the weather as proposed by some. However, forewarned is forearmed. With a little notice we can do plenty to compensate for weather’s effects.

 

Dennis M. Patrick can be contacted at P. O. Box 337, Stanley, ND 58784 or (JavaScript must be enabled to view this email address)

 

Click here to email your elected representatives.

Comments

No Comments Yet

Post a Comment


Name   
Email   
URL   
Human?
  
 

Upload Image    

Remember my personal information

Notify me of follow-up comments?