In the last few weeks, in the South-East of the United States, over 240 tornados touched down in one night and killed over 340 Americans whilst destroying buildings, houses and vehicles like they were toys.
In the meteorological history of the U.S., this is an unheard of event.
No mention of Global Warming in the national news media. Yet, amongst private meteorologists the word was passed in emails…“It’s getting close.”
Here is how Accu-Weather described it:
“From Thursday, April 14, 2011 to Saturday, April, 16, 2011, devastating tornadoes rampaged across communities of the southern United States. Cities and towns from Oklahoma to North Carolina were assaulted by the deadly twisters.
The tornado outbreak led to a total of 241 tornado reports in 14 states over the three-day period. This will likely rank this tornado outbreak among the largest in history.”
And here is how Accu-Weather explained it:
“Three ingredients were in place to allow this violent tornado outbreak to occur from the southern Plains to the Southeast: a powerful jet stream, abundant moisture and a strong cold front.
A powerful jet stream helped to enhance the thunderstorm growth, while moisture surging in from the Gulf of Mexico acted as fuel for the thunderstorms.
A strong cold front plowing across the South was the trigger that initiated the thunderstorm development.
The difference in the direction of wind in the upper atmosphere, southwesterly, and the lower atmosphere, southerly to southeasterly, added a twisting motion that helped the severe thunderstorms to develop rotation. Thus, the wind difference with height, referred to as wind shear by meteorologists, made the severe thunderstorms more likely to produce tornadoes.
There are a couple of factors that are making this year a more active severe weather year compared to normal and compared to last year.”
THE GLOBAL WARMING FACTORS
“There are a couple of factors that are making this year a more active severe weather year compared to normal and compared to last year.
The first factor is that the water in Gulf of Mexico is warmer than last year. This means that there is very warm, moist air in supply for storm systems to tap into and provide fuel for severe weather.
The second is that we are in one of the strongest La Nina patterns in recorded history.
“The strong La Nina pattern means that tremendous contrasts in air masses, with cool and dry air to the north and warm and steamy air to the south, are occurring over the Mississippi Valley. This puts many highly populated areas in the path of dangerous severe weather,” said AccuWeather.com Expert Senior Meteorologist Henry Margusity.”
WHAT THE HECK DOES ALL THIS MEAN?
Understanding weather is tricky.
The average human thinks of hot and cold, wet and dry, windy or calm. Clouds are those white things up there and rain means an umbrella. When it’s cold put more clothes on and when it’s very hot get into the A/C.
Few people think of Atmospheric Pressure and Jet Winds and La Nina or El Nino. (Who are they?)
It is quite similar to a non-surgeon staring into an opened abdomen…everything is red and bloody. (Is that big thing the liver?) Specialties require training.
BUT GLOBAL WARMING IS QUITE SIMPLE
Anything that is heated expands or gets larger. Our planet looks like a soccer ball, but one that is covered with a layer of water (oceans) and then a layer of air.
If you heat these three components, they all expand or get larger. The soccer ball expands and frequently causes earth quakes, the oceans expand, but they also retain their heat, causing El Nino and La Nina and the air expands causing winds in the Jet Streams.
JET STREAMS ARE THE BAD GUYS. WHAT IS A JET STREAM?
Jet Streams are part of the air in the upper atmosphere. You can see replicas in a pot of water which is being heated. The water doesn’t heat up homogenously. The faster moving water molecules blend together and swirl around indecently of the slower moving molecules. This picture is analogous to a Jet Stream.
WHY DO JET STREAMS MOVE SO FAST? GRAVITY OR CENTRIPETAL FORCE?
If you take a weight and attach it to a string and whirl around, the weight will go away from you and will pull on the string. If the weight is very close to you, it will go slowly. It must only traverse the circumference of your body.
The farther away from the center of your body the faster it must travel as the circumference gets larger and larger and the weight must travel this circumference with each turn.
The string is gravity which pulls the air back toward the earth otherwise it would go off into space.
Here is the explanation by Wiki:
“Jet streams are caused by a combination of a planet’s rotation on its axis and atmospheric heating (by solar radiation and, on some planets other than Earth, internal heat).
The Coriolis effect describes how a planet’s surface and atmosphere rotate fastest at the planet’s equator while virtually not rotating at all at the poles. Jet streams form near boundaries of adjacent air masses with significant differences in temperature, such as the polar region and the warmer air towards the equator.”
If we increase the circumference of the atmosphere by heating and making the atmosphere larger we increase the speed of the jet streams.
If we add in hot moist air from oceans and move an air mass over land we have the ingredients necessary to create tornadoes.
This last group of tornados was an historic high. It is the beginning of a new era in high speed winds.