Archive for the ‘Impact of Weather’ Category

TROPICAL STORM LEE 5 DAY PRECIPITATION FORECAST – VALID 8am EDT SUNDAY

Thanks to the National Weather Service Hydrometeorological Prediction Center for this graphic. 

What you see is a 5 day forecast for the total rainfall in inches between 8 AM Eastern Daylight Time Sunday and 8 AM EDT on Friday .  The feared 15″ of rain in the New Orleans area predicted 36 hours earlier seems highly unlikely.  For ease in reading, left click the image two times independently for full enlargement.

Lee Expected To Dump Lots Of Rain In the Next 5 Days!

Thanks to the National Weather Service Hydrometeorological Prediction Center for this graphic. 

What you see is a prediction for the total rainfall in inches between 8 AM Eastern Daylight Time Saturday and 8 AM EDT on Thursday (in other words – a 5 day total forecast).  Already, since this was released, the feared 15″ of rain in the New Orleans area seems highly unlikely due to dry air from Texas being drawn into the system.  For ease in reading, left click the image two times independently for full enlargement.

DAY ONE OF HURRICANE SEASON IS INTERESTING!

Below is a “cut and paste” from the National Hurricane Center’s report for the first day of the hurricane season, 2011.  There is a low pressure system in the Atlantic now making a beeline for my part of Florida and expected to be here around 1 PM.  Item 1 below is the discussion of that system.  At the very end of this posting you will find a link to the page from which this information was cut.  If the graphic you first see is not the satellite image, just left click on it and it should change for you.

My daughter is visiting from New Mexico and this is the day that she and I were to have gone sailing.  However – that activity has been canceled and my “little girl” is sleeping in.  There was a time in my life when I was more daring and would have gone out anyway – working hard to strategically find safe shelter and counting on lots of luck.  But now in my 72nd year I am one to err on the side a caution.  The aluminum mast supported by a steel fore-stay and two steel shrouds all serve as excellent lightning attractors.  I do not wish for my daughter (or myself for that matter) to become a “crispy critter.”  The fun is not worth the risks.  So we will find something else to do.  The tiny red dot on the image below approximates where I live in Florida and the system is traveling toward the west-southwest.  Left click on the image to enlarge.

From my point of view, this is a fitting “sign” that our hurricane season this year is likely to be a busy one.  The post that follows this one will link you to a description of the NOAA summary of this years forecast.

Left Click To Enlarge

 
ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT WED JUN 1 2011

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

1. A SMALL AREA OF LOW PRESSURE LOCATED ABOUT 200 MILES EAST OF
JACKSONVILLE FLORIDA IS MOVING WEST-SOUTHWESTWARD AT AROUND 20 MPH. 
THE LOW CONTINUES TO PRODUCE A CONCENTRATED AREA OF SHOWERS AND
THUNDERSTORMS...AND ENVIRONMENTAL CONDITIONS ARE MARGINALLY
FAVORABLE FOR SOME DEVELOPMENT OF THIS SYSTEM BEFORE IT MOVES OVER
NORTHERN FLORIDA LATER TODAY. REGARDLESS OF DEVELOPMENT...THIS
DISTURBANCE COULD PRODUCE LOCALLY HEAVY RAINFALL AND STRONG GUSTY
WINDS OVER PORTIONS OF THE FLORIDA PENINSULA. THERE IS A MEDIUM
CHANCE...30 PERCENT...OF THIS SYSTEM BECOMING A TROPICAL CYCLONE
DURING THE NEXT 48 HOURS. FOR ADDITIONAL INFORMATION ON THIS
SYSTEM...PLEASE SEE PRODUCTS FROM YOUR LOCAL NATIONAL WEATHER
SERVICE OFFICE. 

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

TODAY MARKS THE FIRST DAY OF THE ATLANTIC HURRICANE SEASON...WHICH
WILL RUN UNTIL NOVEMBER 30. LONG-TERM AVERAGES FOR THE NUMBER OF
NAMED STORMS...HURRICANES...AND MAJOR HURRICANES ARE 11...6...AND
2...RESPECTIVELY.

THE LIST OF NAMES FOR 2011 IS AS FOLLOWS:

NAME PRONUNCIATION NAME PRONUNCIATION
-------------------------------------------------------------
ARLENE AR LEEN- LEE LEE
BRET BRET MARIA MUH REE- UH
CINDY SIN- DEE NATE NAIT
DON DAHN OPHELIA O FEEL- YA
EMILY EH- MIH LEE PHILIPPE FEE LEEP-
FRANKLIN FRANK- LIN RINA REE- NUH
GERT GERT SEAN SHAWN
HARVEY HAR- VEE TAMMY TAM- EE
IRENE EYE REEN- VINCE VINSS
JOSE HO ZAY- WHITNEY WHIT- NEE
KATIA KA TEE- AH

THIS PRODUCT...THE TROPICAL WEATHER OUTLOOK...BRIEFLY DESCRIBES
SIGNIFICANT AREAS OF DISTURBED WEATHER AND THEIR POTENTIAL FOR
TROPICAL CYCLONE FORMATION DURING THE NEXT 48 HOURS. THE ISSUANCE
TIMES OF THIS PRODUCT ARE 2 AM...8 AM...2 PM...AND 8 PM EDT. 
AFTER THE CHANGE TO STANDARD TIME IN NOVEMBER...THE ISSUANCE TIMES
ARE 1 AM...7 AM...1 PM...AND 7 PM EST.

A SPECIAL TROPICAL WEATHER OUTLOOK WILL BE ISSUED TO PROVIDE UPDATES
...AS NECESSARY...IN BETWEEN THE REGULARLY SCHEDULED ISSUANCES OF
THE TROPICAL WEATHER OUTLOOK. SPECIAL TROPICAL WEATHER OUTLOOKS
WILL BE ISSUED UNDER THE SAME WMO AND AWIPS HEADERS AS THE REGULAR
TROPICAL WEATHER OUTLOOKS.

A STANDARD PACKAGE OF PRODUCTS...CONSISTING OF THE TROPICAL CYCLONE
PUBLIC ADVISORY...THE FORECAST/ADVISORY...THE CYCLONE DISCUSSION...
AND A WIND SPEED PROBABILITY PRODUCT...IS ISSUED EVERY SIX HOURS
FOR ALL ONGOING TROPICAL CYCLONES. IN ADDITION...A SPECIAL ADVISORY
PACKAGE MAY BE ISSUED AT ANY TIME TO ADVISE OF SIGNIFICANT
UNEXPECTED CHANGES OR TO MODIFY WATCHES OR WARNINGS.

THE TROPICAL CYCLONE UPDATE IS A BRIEF STATEMENT TO INFORM OF
SIGNIFICANT CHANGES IN A TROPICAL CYCLONE OR TO POST OR CANCEL
WATCHES OR WARNINGS. IT IS USED IN LIEU OF OR TO PRECEDE THE
ISSUANCE OF A SPECIAL ADVISORY PACKAGE. TROPICAL CYCLONE UPDATES
...WHICH CAN BE ISSUED AT ANY TIME...CAN BE FOUND UNDER WMO HEADER
WTNT61-65 KNHC...AND UNDER AWIPS HEADER MIATCUAT1-5.

ALL NATIONAL HURRICANE CENTER TEXT AND GRAPHICAL PRODUCTS ARE
AVAILABLE ON THE WEB AT WWW.HURRICANES.GOV. SIGN UP FOR PRODUCT
UPDATES BY EMAIL AT WWW.HURRICANES.GOV/SIGNUP.SHTML...IN ALL LOWER
CASE. YOU CAN ALSO INTERACT WITH US ON FACEBOOK AT
WWW.FACEBOOK.COM/US.NOAA.NATIONALHURRICANECENTER.GOV.

$$
FORECASTER BERG/PASCH
NNNN

Here is a link to the National Hurricane Center Home Page: http://www.nhc.noaa.gov/gtwo_atl.shtml  

Tomas May Invade Haiti as a Hurricane

Plot Courtesy of Jonathan Vigh - Colorado State University

Even when you left click twice to get full enlargement, most of the individual model forecast plots are hard to read individually because of the “cluster” of agreement in anticipated general trend.  The only glaring exception you see is the CLP-5 which should be no surprise to those who study these spaghetti charts.  CLP-5 is the “CLImatology-PERsistance model 5-day” of the National Hurricane Center and is sometimes referred to as the CLIPER model for obvious reasons.  It tends to project the path of tropical systems as though they were going to conform to their “past track.”  So, more often than not, when there are changes in the steering influences the storms actually stray significantly from the persistence route.  Most other models account for anticipated steering changes.  This does not mean that the CLP-5 is of no value.  To the contrary, it is very useful tool particularly in accessing forecast accuracy of other models.

It appears that Tomas could become a serious problem for Haiti.  The country is over 98% deforested and that opens up a whole can of worms with regard to flooding, mud slides, and soil erosion.  Some small fraction of the deforestation has been due to natural causes (e.g. Hurricane Hazel in 1954) but the vast majority has been due to the impact of humans and their practices upon the environment, the poor management of same, and the general human and political condition. It is my sincere hope that the storm weakens significantly but the National Hurricane Center currently has the “weighted mean” plot (within the cone of uncertainty) taking it through Haiti as a hurricane.

I copied this 2002 image below using my free Google Earth download.  With yellow it shows a small part of the border between Haiti and the Dominican Republic at the Artibonite river.  The greater amount of deforestation on the side of Haiti (west or left side of the river) is clearly evident.  The eye altitude is 26,293 feet; a horizontal scale appears on the lower left.

Image Courtesy of Google Earth

My dear, long-time friend, Chuck Knighton, and his wife, Helen, are residents of northern Barbados and as of yet I have heard no news.  I do know that they have frequent power interruptions with ordinary thunderstorm weather – so communication could be down for quite a while.

Update on that 1:40 pm EDT 11-1-2010 – An e-mail from Chuck’s mother:

“Hi Toney,
Thanks so much for calling about the situation in Barbados! I have just recently spoken with Chuck’s sister in law who lives in the south of Barbados. She reports that they are all OK and the property sustained fallen trees and lots of rain! They do have household water, AND electricity (praise be!) and no one sustained injuries. Great news! They do not have phone service as yet, and I was really glad to have touched bases with someone!
Thanks again!!”

The Hurricane Season of 2009 Has Begun!

6-1-09 HurricaneBegin

MOST IMAGES ON THIS WEBLOG ENLARGE WITH LEFT CLICKS

This image shows no tropical activity 15 minutes into our 2009 season (not surprisingly) but you can clearly see the clouds development with a stationary front cutting diagonally across the image.

The Atlantic/Gulf of Mexico/Caribbean hurricane season “officially” begins on June 1.  The fact that Tropical Depression 1 formed about 4 days before the official season’s beginning is not an indication of an active hurricane season this year.  There seems to be no relationship between early activity and the “busyness” of that season.  In fact, there is a real possibility that an El Niño event will be strong during what we consider the peak activity period of our season (the approximate middle of the 6 month long period).  Eastern Pacific sea surface temperatures have been rising steadily for the last several months pointing to the El Niño possibility.  That means is that our 2009 season might be less active than usual if the ENSO comes to fruition.  ENSO = El Niño Southern Oscillation.  BUT, even if a strong El Niño develops it is no time to let down one’s guard if living in “hurricane country.”  1992 was an El Niño year and that was when Andrew occurred.  My house in Homestead was a total loss.

I was extremely well prepared back then (August 24, 1992) but hurricane Andrew slammed in as a category 5.  However, we did have a plan and it worked to the degree that no one in my family was physically hurt.  Only one window had a small crack but – the roof failed and the damage was almost beyond belief for us.  Since Andrew was a relatively dry storm our windows holding firm did make it so that we were able to salvage some valuable items afterwards because the wind did not gut the house.

We stayed in the community and helped rebuild.  We had great insurance and our house was reconstructed in one year to a higher standard.  During that time we four lived in a 25’ travel trailer that I purchased for that purpose but kept for several years afterwards to use for recreational and educational travel.

If you live in “hurricane country” then you have choices.  Some of us have more choices than others but you should at least have a plan that is clearly articulated to and understood by each member of your household.  Shall you be well prepared or do you choose to become a potential victim who is dependent upon others almost immediately after a storm?

I urge you to follow to the best of your ability those preparation suggestions made by your local and federal agencies.  Some of us are more fortunate than others in what we are able to do to protect our dwellings – that is, those of us who are lucky enough to have a place we call home.

In my new post-retirement community and in neighboring communities (Citrus and neighboring counties)  I see what I consider to be real paradoxes or, at the very least, some irony.  I’m reminded (but to a somewhat lesser degree) of one of my Homestead neighbors who drove a Mercedes while his wife drove a BMW; they owned a very large boat moored at a dock in nearby Biscayne Bay, an ultra-light aircraft and a twin Cessna – yet they had no window protection of any sort for their home.  I speculate that it was not a matter of the cost of such protection but more a matter of priorities and life style with perhaps a little measure of denial thrown in.

Some people in my part of Florida feel that by being inland they have some sort of immunity to the ravages of hurricanes.  Yes – it is an advantage being inland, especially if on high ground but it does not offer any guarantees.  Most deaths in hurricanes (on the average) are due to high water and being away from the storm surge zones and areas prone to flooding from the storm’s downpours makes for a safer situation – generally speaking.  But, high winds can play havoc particularly when items become projectiles in the wind.  It is a fact that if the wind velocity doubles, the force it exerts upon a surface it is striking at right angles quadruples!  People in my part of Florida experienced a lot of activity if they were here in 2004 but the wind velocities were luckily relatively low.  Only modestly higher wind velocities would have produced exponentially greater force and far greater damage.  Furthermore, tornadoes and microbursts occur within hurricane bands and neither have a preference for locations near the coast.

Come early August we will have been in our new home for four years.  Our first major purchase when moving in was window and door storm protection.  We had tended to that “need” before we were even set up with a cable connection for our televisions and computers.  For the first two years that we were here I participated in a number of hurricane expos as the “hurricane resource person” on site.  There were expo participants who were in the business of selling, fabricating, and installing storm protection to homes and businesses.  Most visitors were there to learn about hurricane safety and hurricane protection.  But one particular type of visitor seemed to come to these expos in order to exercise their debate skills on the pros and cons of storm protection for windows and doors.  I was amazed at times by the level of denial and warped rationalization that I witnessed.  Some argued that they refused to concern themselves with such matters and would just let their insurance take care of it for them.  There was little if any consideration for how they would deal with losses of personal items, safety issues if they were not to evacuate, safety issues if they were to evacuate, where they would go if they did evacuate in time, and how they would handle matters when they returned if things were torn all to hell!  I am convinced that some of the men I talked to felt that it was a manly thing to face a storm raw without preparation – even though in some case it meant leaving their house mates far more vulnerable than necessary.  To my mind, they had it backwards  – a real man takes care of his own and is available to help others as well.

I can testify, by experience, that the trauma of a storm itself often does not compare to the trauma of the immediate aftermath and rebuilding.  Looting, for example and other forms of predatory behavior can occur.  In heavily damaged areas the majority of those who come to help are good people with good intentions but there is one whole class of “helpers” who are there to take victims for a ride they will never forget.  In South Dade County, where Andrew first struck the U.S.A. the divorce rate just about doubled for the next few years.  Stress and anxiety were on a very high level.

So – please think in terms of the big picture when a hurricane visits – not simply the weather event itself.  Think in terms of what you’ll do if you lose electricity for several days and how you will fare food-wise if you need to go for a week or more without provisions and how you’ll communicate.  Cell phones go out of commission when the transmission and relay towers are damaged.  Then there are the special needs people who absolutely must make arrangements for care in the event of a serious storm.

Please be prepared to the best of your ability.  If you later consider all of that planning and work to be for naught because no hurricane occurs in your region – there will be more seasons to follow for which you will again be ready and if, near the end of the season, you have a box full of “emergency food” there are surely some places near where you live to donate it to the needy.  After all, the end of the official hurricane season (November 30) and Thanksgiving (November 26) are pretty darned close to each other.

Here is this season’s list of names; tropical cyclonic systems will receive names in order from this list once they reach tropical storm intensity; tropical storm sustained winds fall in the range of 39 mph to 73 mph; of course they retain their names if they become hurricanes (74 mph or more):

Ana
Bill
Claudette
Danny
Erika
Fred
Grace
Henri
Ida
Joaquin
Kate
Larry
Mindy
Nicholas
Odette
Peter
Rose
Sam
Teresa
Victor
Wanda

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Pilot Error May Have Caused Crash Near Buffalo

Most images on this site enlarge with left clicks

Most images on this site enlarge with left clicks

What so many have been reluctant to say – probably being extra cautious because nothing is certain at this time – was finally printed in yesterday’s Wall Street Journal.  In my first posting about this terrible aircraft accident I suggested that if icing was indeed the problem – the accident should never have occurred.  Now – it is beginning to look as though the “reaction” to icing might have been incorrect causing the aircraft to immediately stall.

Please be mindful of the fact that the investigation of this accident is still in a very early stage.  Here is a link to the WSJ article:

http://online.wsj.com/article/SB123492905826906821.html

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RECORD LOWS COMING FOR PARTS OF FLORIDA

Left clicks enlarge most images on this site

Left clicks enlarge most images on this site

RECORD LOWS ARE EXPECTED FOR PARTS OF FLORIDA ON FRIDAY NIGHT AND SATURDAY MORNING.  I AM EXPECTING BELOW FREEZING WEATHER WHERE I LIVE IN NORTHEAST CITRUS COUNTY.  PLEASE GO TO THE FOLLOWING SITE FOR MORE DETAILS:

http://www.srh.noaa.gov/images/tbw/pdf/TopNews/RecordColdFeb21.pdf

THIS POST AND THE LINK ABOVE ARE TIME SENSITIVE.

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Icing Once Again Is Primary Suspect in Bombardier Dash 8 Q400 Crash

bombardier_dash-8-4001

The cause of last Thursday’s terrible airplane crash near Buffalo, New York may never be know for sure.  In any case, such investigations take many months.  There was a brief period of time when there were some significant doubts as to the role of icing in the accident – partly due to the embryonic stage of the investigation hindered by the complexities of carefully sorting debris of the aircraft and the house from the remains of the victims.  What a difficult job that must be.

Yesterday and today there have been more indications that icing was responsible.  If anything accurate can be said about the nature of the environment which produces icing conditions it is that it is fickle.  Just as the surface has its own micro-climatology, so do clouds.  It appears to me that the plane that crashed must have entered an icing environment which might have been severe.  There is also a possibility of some form of mechanical and/or instrument failure.  The final determination could very well point to a combination of unfortunate happenings.

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ICING AS PART OF THE HYDROLOGIC CYCLE – SOME BASICS

LEFT CLICK TO ENLARGE
TWO SEPARATE LEFT CLICKS TO ENLARGE

THE HYDROLOGIC CYCLE, A CLASSICAL TOPIC

IN NATURAL SCIENCE COURSES

I’ve taught the hydrologic cycle many times in geology, meteorology, physical oceanography and environmental science classes.  It’s always been a pleasure but I’ve never had enough time.  All of these were college courses and in almost every case the text book covered the subject adequately.  However, the manner in which water moves and changes in our natural environment is so very interesting that a few pages in a text with a traditional drawing and an hour lecture from me simply does not do the subject justice.  Water is such a remarkable compound – I can’t find the words to explain how very interesting it is and how mysterious it can be at times considering the amount of scientific attention it has received through the years.  There is still so much to learn.

So, it is with excitement that I look forward to a 6-hour course that I am scheduled to teach in May to the Senior Institute enrollees at Central Florida Community College.  In 37 years of full-time college teaching (and 4 years part-time) I never had the opportunity to devote so much time to the subject.  The method I intend to use is my own “idea” but surely it has been done before – that is, to follow water step-by-step as it goes from one phase or one environment to the next.  My presentation won’t be a journey without side trips and backtracking.  There are multiple manners in which water can transform and/or move with interesting little anomalies along the way.  With 6 hours to utilize I will be able to discuss aspects that were only fleetingly mentioned in my previous hour-long presentations e.g.: Capillary action, deposition, glacial calving, influent groundwater movement, juvenile water, super-cooled droplets, and much more.

SUPERCOOLED CLOUD DROPLETS AND ICING

I feel fairly certain that some people who read this have had the experience of having rain freeze upon impact with their vehicle’s windshield.  Some would assume that the freezing occurs because the windshield is so very cold.  That is usually not the case.  Instead, the liquid droplets were probably at a temperature well below “freezing” and the impact with the windshield itself triggered the instant freezing.  Hopefully, the “defrosting” vents can keep the windshield warm enough so that the ice can be quickly cleared.  Now, imagine what it must be like if the surfaces being iced are the windshield and wings of your aircraft in flight – as well as other aircraft surfaces (e.g. propellers, fuselage, horizontal stabilizers)!

Today, February 15, 2009, the mere thought of super-cooled droplets hauntingly reminds me that in addition to the marvelous beauty of water’s multifaceted journeys and transitions through our natural environment, there are some insidious elements that can become deadly in this modern world.  Of course, I’m thinking specifically of the recent terrible aircraft accident responsible for 50 fatalities near Buffalo, New York.

PURE SPECULATION

For a short while since the accident it appeared that icing might have been the culprit or perhaps a contributing factor in causing the aircraft to make its sudden rapid descent (apparently almost immediately after the application of flaps).  At the time other aircraft in the vicinity were reporting icing.  HOWEVER, AT THE TIME OF THIS WRITING, NEWS RELEASES HAVE INDICATED THAT THE NATIONAL TRANSPORTATION SAFETY BOARD CLAIMS THAT ICING APPEARS NOT TO HAVE BEEN A FACTOR. The changing of the airfoil’s shape upon flap engagement might have triggered the rapid descent – an apparent stall leading to a flat spin.  That would indicate either insufficient air speed at the time of flap deployment or some type of catastrophic failure.   SINCE MANY AVIATION ACCIDENTS HAVE BEEN CAUSED BY ICING – AND IT WILL REMAIN A PROBLEM FOR AIRCRAFT FOR A LONG TIME TO COME, I SHALL CONTINUE.

When icing was being blamed, I suspected that some critical errors might have been made in the cockpit.  At best, my notions were intuitive – or, on the other end of the spectrum, unfair during such an early stage in the investigation.  Nevertheless, a surprising amount of information has been made available during this embryonic phase – partly due to the fact that the flight recorders are advanced models and they were in very good shape.  There is no need for me to dwell on factors that can cause a plane to become unstable when icing occurs – suffice it to say that airfoils lose “lift efficiency” quickly when ice buildup changes their shape and of course the weight of the ice accumulation can also be a huge factor.  I do not know what kind of air speed indicators are installed on that type of aircraft but I do know that icing can cause false readings on some types.  Icing can also cause problems at air intakes and oil cooler intakes of some aircraft.

glls-labeled-bw4BUT WHY DOES THE PHENOMENON OCCUR

IN THE FIRST PLACE?

The cause of the icing is a surprise to most people.  Though icing can occur on a plane’s very cold surface when it descends into “warm” clouds whose temperatures are above freezing, the vast amount of problematic icing occurs when the liquid droplets themselves are below what we traditionally consider freezing temperature.  These droplets consist of what is called supercooled liquid water (SLW).  Water in cloud droplets can get as cold as about negative 40 degrees Celsius (which is the same as negative 40 Fahrenheit) without freezing.

When liquid water freezes (box 3 to 4 in the illustration above) the water molecules align in a crystalline fashion.  But in order to do so they need one of two things:  1) either a freezing nuclei whose surface acts as a template to initially “show” the molecules how to (or trigger the molecules to) line up, or 2) some molecules themselves must be jolted (or jiggled) such that for at least an instant they are arranged so they can act as a template or model for the rest to follow.  The likelihood of such alignment occurring in undisturbed droplets is slim.  This would not be true of most fresh water at the surface, such as in lakes because there are microscopically-sized particles available in the water to act as templates.  On the other hand, water that has condensed and remains in the air is very “clean” by comparison.

An aircraft flying though supercooled cloud droplets causes considerable rapid stirring to set the stages for freezing upon impact with that aircraft – just as supercooled raindrops freeze upon impact with trees and suspended wires in those notorious, damaging ice storms.

VIDEO DEMONSTRATIONS

The first three links below show convincing demonstrations of liquid water freezing as a result of hexagonal ice crystal seeding.  The ice crystals provide the template which “shows” the liquid water what to do in order to become solid.  In the third example when the water freezes and builds up a small mound on the wooden post, I suspect that the split second ideal alignment of some water molecules (while pouring) provoked the freezing.

http://www.youtube.com/watch?v=Xe8vJrIvDQM

http://www.youtube.com/watch?v=gGpNhBPYNfs

http://www.youtube.com/watch?v=4g1BDpU7ZQo

In this 4th example you will see that a jolt causing a sloshing of the water in the small amount of air space at the top of the bottle allows for enough water movement so that for an instant a hexagonal orientation occurs among some molecules causing a very rapid “follow the leader” freezing all the way down to the bottom of the bottle.

http://www.youtube.com/watch?v=DpiUZI_3o8s

Just as condensation and deposition give off heat, freezing is also exothermic.  This is probably why some of the water remains in the liquid state.  If the SLW is not very much colder than “freezing” temperature, the heat given off during freezing will cause the remaining liquid to acquire enough heat to teeter over to the liquid side.

Use the search term “supercooled water” on YouTube.com and you will find many other video demonstrations.

WHEN WATER FREEZES IT EXPANDS, BECOMING LESS DENSE.  THIS EXPLAINS WHY SOLID WATER FLOATS UPON LIQUID WATER.

If you compare box 3 and 4 in the illustration in this post, you will see why water expands and becomes less dense upon freezing.  To establish the hexagonal grid necessary for ice, the molecules can’t be as close together as they were when they were in the cold liquid stage.

Information on supercooled liquid water would have eventually been posted here if the Continental Express Flight 3407 disaster had not occurred.  It is regrettable that the accident played a role in my posting this information at this time.  I offer my sympathy to all who have broken hearts over the loss of a loved one and all others adversely effected.

Finally, the information in this post about SLW and icing merely scratches the surface compared to that which is known.  But, that which is not understood is formidable.

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