Atmospheric Cooling = Strong Tornadoes

31 05 2011

We interrupt this rant for this special announcement.  Our cold spring in the northern plains is wreaking havoc in the form of tornadoes in the southern and middle parts of the country.

I think the weather phenomena had a lot to do with my interest in mechanical engineering.  Growing up on the farm in the flatlands, I had seen a great many black clouds approaching on the horizon.  As they drew closer, they would either brighten to a lighter gray and rain, or they get ugly.  If the approach is led by a dark band of clouds followed by blue-green solid color all the way to the horizon, there would be some serious energy release.  If there is continuous rumbling, it generally means hail – tornadic-type winds aloft.

Weather should marvel any mechanical engineer with interest in the thermal fluids side of the curriculum.  All weather conditions are driven by temperature differences in the atmosphere and it’s influenced heavily by ocean temperatures to the west from which prevailing winds and jet stream flow, at least in the northern hemisphere.  It’s a massive thermodynamic, fluids, and heat transfer model.

What is causing this year’s massive tornadic outbreak?  Unusually cold mid and upper atmosphere derived from cyclically cold Pacific waters.

The two best weather guys I’ve seen in the business are Tom Skilling from WGN and Joe Bastardi from AccuWeather.com.  Bastardi is a historian and doesn’t get whisked away with the hype.  He states the mid levels of the atmosphere have cooled very rapidly in the past year as it did 60 years ago.  Did you know this?  No.  Why?  Because nobody is reporting it.  This makes sense because powerful storms, which are like engines, are driven by great temperature differences; NOT an overheating atmosphere.

Tornadoes form when warm air from the southeast plows into cold air from the northwest.  The warm, moist air rises into the cold mid levels of the atmosphere, and of course what goes up, must come down.  Condensing water vapor turns to rain and if cold and turbulent enough develops hail falling to the ground cooling the air as it falls.  This air flow can become strong enough to cause straight line downdrafts that can flatten buildings and trees like a tornado.  When the warm air channels, it can become like the vortex in your bathtub or sink.  It will start to rotate to form a tornado.  For a great cartoon of this, click here.  For the real deal, see this minute-long video from National Geographic – devastating.

Fortunately, the pattern that set up these storms in the south just broke over the weekend.  Hopefully, we won’t get our turn in the north but it’s certainly possible.  The jet stream, or line between cold and warm air has lifted far north, hence the warmer weather we are experiencing in the north.

All engines, including power plants, your car’s engine, jet engines, are driven by hot and cold sinks.  The greater the temperature difference, the greater the power, and efficiency.  A tornado is an engine. It is driven by temperature differences in the atmosphere and the “load” is the destruction it wreaks on the ground.  When towns like Joplin, MO appear to be run over by a giant lawnmower, the giant lawnmower requires tremendous power, delivered by an F4 or F5 tornado.

This presents an opportunity to generate electricity.  No; not from tornadoes, but from waste heat being dumped from power plants.

I would guess that when anyone thinks of a nuclear plant, they think of these cooling towers.  These towers work on a very simple concept.  Warm water from the power plant is pumped to the top and showered down through the tower.  Openings at the bottom let in cool dry air from the surroundings.  The warming and humidifying of the air causes it to rise and a natural draft occurs.  Therefore, fans are not needed.  Towers need to be tall enough and shaped like they are to generate sufficient air flow via “stack effect” to provide required cooling capacity.

This presents an opportunity to generate electricity.  Not just from the vertical rise in the tower, but all the way to the upper atmosphere.  If rotation were induced, an engine could be developed between the hot exhaust and the always very-cold upper atmosphere – a standing tornado, essentially.

Don’t laugh.  I first came across this in one of the power industry’s trade magazines a year or two ago, and it made a lot of sense.  It’s called an atmospheric vortex engine.  Here is a good paper on the topic from the Canadians, ay?

So I ask, why is the DOE not pursuing something like this, rather than the STUPID electric car?  Silly me.  This is potentially cost effective energy efficiency with huge potential from a ubiquitous plentiful source of free waste energy; not an ALICE IN WONDERLAND pipe dream.  If we can build nuclear reactors and sophisticated huge steam turbines, surely this simple concept can be harnessed.

Seventy percent of energy required to fuel a thermal power plant (natural gas, coal, nuclear, fuel oil) is dumped to the surroundings.  Think of the potential – and nothing extraordinary is required.  Nature takes care of the vast temperature difference to drive the engine.  The efficiency of this second heat engine would be approximately 30% per the above paper.  This could take conventional power plant efficiency from the standard 30% to roughly 50%, roughly a 70% increase.  This is enormous.

Tidbits

I’ve always considered global warming to be driven by politics and self interest, knowingly or unknowingly – as in, I can make money from this.  It is fanned by sensational films like that described in the aforementioned Dumb Bear post, Al Gore (who’s film the UK banned from its schools) and even National Geographic – it sells – see how it works?  It’s easy.  More below.

The very cold spring and gobs of snow this winter have been devastating.  Dude!  Aspen reopened for skiing over the Memorial Day weekend – with more base now than it had on New Years Day!  This is normal?  It’s insane!  Mammoth Mountain in the Sierras still has 200-plus inches of snow – plan to ski through July 4!

How does paranoia void of logic and reason perpetuate?  The Center for Decision Sciences at Columbia Business School did a survey of 1,200 in-duh-viduals, “Those who felt that the current day was warmer than usual for the time of year were more likely to believe in and worry about global warming than those who thought it was cooler outside. They were also more likely to donate the money they earned from taking the survey to a charity that did work on climate change.”  Even if INDOORS is hotter, people tend to fear global warming more!

In other findings: if you eat soup frequently, check with an emotional counselor; want that job, wash your hands in hot water just prior to interview; worried about crime, get out of dodge when it’s hot outside.

written by Jeffrey L. Ihnen, P.E., LEED AP