Saturday, August 25, 2007
The Full Sturgeon Moon follows on August 28th, at least according to the Farmers Almanac. Interesting, that's what Indians called it in the Great Lakes area, not that we have any sturgeon down here. By the Harvest Moon a month later, summer will be over for good and cool fronts should be headed our way.
Unlike many tourist spots, our traffic inevitably stops in mid-August, to be followed by some special weekends for the bikers and sand castle lovers, and then blissful peace until the Winter Texans arrive. Time clicks away on our Island according to its own clock, no matter the calamities or weather, inexplicably marching onward like migrating butterflies.
Thursday, August 23, 2007
It is amazing that for all the science we have today, we still can’t figure out how ocean waves work. I will spare the reader a lot of technical voodoo, but ocean waves are themselves chaotic events, and while we can record them we still do not understand them. Here is my feeble attempt.
At first I was interested in storm surge, which usually comes along with a hurricane. Previous media releases said Hurricane Dean could produce an 18-foot storm surge with 12-foot waves on top of that. That would add up to a massive 30-foot tall column of water. Indeed, some of the largest storm tides are about 30 feet high, so this was not unrealistic. However, it turns out that what we call “waves” and “surges” are incredibly complex. Consider the following graphic:
What this says is that wave height includes the trough, which can be roughly half the size of a standing ocean wave. Indeed some of the largest waves ever recorded, possibly 100 feet tall, have some of the deepest troughs. To avoid much of the problem with figuring out storm surge versus wave size, most authorities now simply record “storm tide,” which takes into account many things at once including the tide, rainfall, barometric pressure, ocean waves, and the large blob of water being pushed by a hurricane. Conceptually it might be presented as in the following diagram, but is expressed as a single number in terms of feet or meters above mean average tide datum.
This is not the greatest depiction because the storm tide should include some wave action, maybe half, and there is a great deal of evidence that waves actually get smaller when up on the beach because rotational energy has been spent. More about wave set-up and swash run-up later, as this stuff is only beginning to be understood and modeled correctly – or shall we say more elegantly.
From a conceptual view, not all storm tides are created equal, since a hurricane spins counter-clockwise. This means that most of the hurricane surge will be on the right-hand side of the cyclone. This is not to say that there is no hurricane surge surrounding and following the eye on both sides, but that maximums will be located as indicated below, on the front right quadrant.
Depending on storm direction, angle of attack, severity, and fetch (duration over water) the left or weak “subsidence” side of the storm may have a large storm tide, such as we saw when Katrina hit New Orleans, or have the unusual effect of sucking all the water out of the bays until they are nearly dry. Implications for South Padre Island could be that under certain conditions, a glancing blow offshore could cause Laguna Madre to create a storm tide that could flood the island from the bayside.
Most conventional models used by emergency planners these days only estimate storm surge and are notoriously very crude. They do not take into consideration the effects of diminishing wave heights near-shore, or the effects of wave set-up and swash run-up. Most wave heights are recorded offshore where they are at their maximum; as they run into the five or six sandbars that parallel our coast, they tend to break, thus releasing their energy. That is why 15-foot waves offshore might only be 5 feet tall when in the beach zone. This effect is called “wave set-up” and depending on the area can cause diminished waves onshore or in other places generate huge monsters (e.g., waves off Australia). Once the ocean wave finally breaks for the last time and travels up the beach that is called “swash run-up.” The swash is what causes most of the erosion, damage, and flooding here on South Padre Island.
The picture shows wave swash on a fairly steep beach, and not only increases storm tide height but also can have a horizontal distribution inland as well. After the swash expends its force, water rushes backwards to the ocean like a giant vacuum cleaner, called swash return. This is the main reason why we lose sand off our beaches during major cyclones.
In conclusion, I do not claim to be on the forefront of science, as all I wanted to do was to introduce some new concepts and go onto say that since Katrina, scientists have renewed their efforts to understand what we thought were very simple things. I found several hundred academic articles written between late 2005 and the present. Scientists are still baffled by it all, such as how the storm could blow giant tumble-weed balls of trash 50 miles inland, and why we would find debris from 50 miles inland way out in the ocean, seemingly all at once. The fact is, we simply don’t understand waves.
Wednesday, August 22, 2007
Above: a screen shot from Sandy Feet's "Sandcastle Inn" webcam where we just fixed the camera angle. Below: Sammie and one seagull on the beach.
Hurricane Dean just went inland at 20.5 degrees latitude near a village called Poza Rica (1:00 CDT). It’s all over now except a few waves coming ashore, not as impressive as the surfers hoped, but maybe eight to twelve feet on the outside – and I’m not swimming out there to check for ya!
The Island is nearly deserted now, and most of the government stuff has been ordered to “stand down” and head back north. The list is rather impressive – and before I go further, some people did object to my last posting about the bureaucrats but as I said, it was the weather model arguments and not the great emergency preparation itself, from top to bottom.
· Six C-130 military cargo planes
· Activation of all surrounding Coast Guard and Navy helicopters and vessels
· 3,000 urban transit and school buses
· An unknown number of Texas National Guard troops (perhaps 1,000 vehicles)
· 80,000 barrels of gasoline
There is much more than this list, such as the overtime from local officials, the TxDOT, and all Border Patrol. The 80,000 barrel statistics sounds a little funny – perhaps gallons is more like it because that much fuel would be 3.4 million gallons, or about 420 semi truckloads of gasoline. Regardless, I’d like to thank all the officials and worker bees.Now could somebody please tell all the tourists it's OK to come on back?
Monday, August 20, 2007
Thanks to SciGuy over at the Houston Chronicle, we're starting to sniff the massive emergency ops in Texas and detect a noticeable stink. The Governor down to all the locals have been maintaining that Hurricane Dean could smash into Texas late Wednesday, and have mobilized even more equipment and manpower. The reason is because two model tracks come to Texas, as is shown in the above graphic (thanks, Eric!).
As SciGuy proves, the two tracks coming to Texas either (1) aren't models or (2) so dumbed-down as to be useless. What the heck is going on? Or as SciGuy asks in his blog, "Anyone else found hyperbole with regards to Dean in the last week?"
Seeds of the story seem to come from two immediate sources, a spokesman for the Brownsville Weather Service and Lieutenant Governor David Dewhurst, the latter of which shared the news on Fox TV (see a pattern here?). The offending quote from the Brownsville NWS reads:
"We're in full swing. There are still a couple of models that show us getting a direct hit."
What a load of pure, unmitigated crap. I should have known better last night when mysterious, anonymous bloggers were preaching on the Weather Underground blog that "Dean is shifting north right now; Texas WILL be hit." Then this morning I read the Valley Morning Star, our local newspaper, and about blew coffee ('Tracking storms no exact science,' Amanda Harris, August 20, 2007). You guessed it, Amanda quoted a spokesman for the Brownsville Weather Service.
Conspiracy or not, it does appear that from top to bottom, the emergency planners were struck by an intense lightning bolt of dumb-ass. Get over it, folks, there is no three-story wall of water coming to flood SPI this week, and Hurricane Dean is headed for landfall south of Cozumel and then south of Tampico, Mexico. You don't have to justify spending tens of millions of my tax money on some kind of stupidity and folly.
Sunday, August 19, 2007
Should I stay or should I go now
If I go there will be trouble
An' if I stay it will be double
- The Clash, 1981
Today is Sunday, the day I had selected to make a choice as to whether to boogie from the Island. So far, the models and forecasts all push Hurricane Dean further to the south into deep Mexico. You do have to read the fine print, which notes that all hurricanes wobble and inexplicably change course; the final landfall could be off by 50 miles or more. So far, I'm staying, although Monday and Tuesday could be bellwether days.
So far, the Town is under a state of emergency, the County has a call for voluntary evacuation, and even the Governor and President have taken special measures in anticipation of Dean. A bunch of boats and RV's left the Island yesterday, although I'm not aware of any businesses closing. Most renters will honor cancellations and repay deposits or re-book reservations, so ask if you're feeling nervous about things.
TROPICAL UPDATE. Most models now put Dean 250 miles south of South Padre Island, so as the SciGuy at Houston Chronicle says, we might not even feel tropical storm force winds. Science Dude also notes that due to eye-wall replacement cycles, Dean is currently weakening - but don't count on that as the storm approaches Cancun and Cozumel, which was raked by Wilma and many other famous cyclones - they've just finished reconstructing the shoreline there.
The reason for the shift in Dean's forecast track is because of the strong upper level low which can be seen spinning in the middle of the Gulf of Mexico, as well as a massive area of high pressure filling in behind it. [This loop requires a ton of memory and a high speed connection, so for a low-res still picture click here and go to Gulf of Mexico-water vapor.] You should see the leading NW edge of Dean in this picture.
Once across the Yucatan, Dean is expected weaken sustantially and then gain some strength before making landfall again near Tampico, Mexico.
Saturday, August 18, 2007
SOUTH PADRE ISLAND. Islanders began preparing for Hurricane Dean today with some plywood and shutters going up. For the third or fourth day straight, most models indicated the lower Texas and upper Mexico coast as the likely target after crossing the Yucatan Peninsula. So I started some preparations, had the truck looked at (what the heck is that noise?), and got ready for plywood duty.
While is seems inevitable that the hurricane would hit us squarely in the face, it should be said that Dean is several thousand miles away – 500 miles east of Puerto Rico. These storms get so large they basically make their own weather and go where they want to go, like the biggest Brahma bull in the barn. Even the experts say that predicting any tropical cyclone over 72 hours is highly uncertain to almost be meaningless (sorry, Town Emergency Team). Here’s why:
As indicated in the attached graphic at the top, an upper level low is circulating over Florida and the Bahamas. Since cyclones spin anti-clockwise, the upper low will prevent Dean from moving much to the north because of its spin that would push back on it. This low is predicted to remain about the same force and make a parallel track to the west, just like Dean. So no change in the upper level low in relation to Dean as they both move, Dean will continue marching a little north of due west.
Ah, but what happens is Dean slows or the upper low slows, or the upper low moves way in front of Dean? That could result in major changes to the forecast track. Indeed one of the best hurricane models called GDFL predicted that Dean would fall behind the upper low; due to the spinning action, Dean would be shot right to New Orleans like a circus clown out of a cannon.
What happens if Dean weakens over the Yucatan and the ULL collides with it, for some reason or other? This could result in a “super-cane” such as the move and the book, The Perfect Storm. Such a massive storm would probably be blown towards Florida by the subtropical jet. But we can only surmise and use the best current predictions we have. I’ll update this later tonight.
Tuesday, August 14, 2007
Sunday, August 12, 2007
Well I guess SPI is safe from the dreaded "Dead Zone" that formed off the Brazos River outfall in the Gulf. That blue color means freshwater from recent rains and because freshwater floats on top of saltwater, you can measure it from outer space, very cool. The blob has slumped a little south in our direction, but has diluted as it progresses. Such a vast pool of freshwater could put the damper on local fishing and make the water look pooh-brown like the Brazos, but I don't think that the oceanographers ever documented hypoxia occurring - such as the huge dead zone off the Mississippi which truly cannot support marine life; the Mississippi dead zone is more noted for agricultural runoff that causes algal blooms, bacteria, and loss of oxygen.
Plus, if we get one or both of the tropical depressions or waves in the Gulf, the wave action should break it all up pretty well.
On the topic of wave action, Gene Gore is heading over to Hawaii to check out Hurricane Flossie surf, and should have a report about Labor Day or so.
Saturday, August 11, 2007
I guess this is stepping back into the political fray, but it is an important issue to bring up: the immanent crackdown on illegal hires at businesses in the US. Homeland Insecurity leader Chertoff announced that these rules could cause some problems in industries such as agriculture, retail, apparel, and construction but said he had no intention of punishing Congress for not reforming the immigration laws – if you believe that, I have a second bridge to sell you in Death Valley, or maybe an island off Alaska with nobody living on it.
It is coincidental that this is happening just as the housing equity market ended up in the toilet, causing central banks all over the world to have to inject hundreds of billions of dollars into reserves so as to keep the market liquid – this liquidity is needed because like oil in an engine; if you don’t have it then entire engine would seize up. Gosh I hate it when I predict these calamities and they prove more than half true.
The funny part about all this is that many of the same folks who voted against Bush’s immigration proposals have huge holdings in agriculture, construction, hotel services, and in a round-about way are employers of illegal aliens! Obviously, the need to placate voters was much stronger than their personal bottom line, for which we I suppose should be very grateful. The word “altruistic” seems a little awkward, however.
So right when Congress votes to expand farm subsidies for vegetables and fruits (most goes to cotton, corn, and soy beans) there’s nobody left to pick the stuff. Immigrants are either vanishing into the underground cash economy or are headed back home. If remittances such as wire transfer money back to Mexico are any indication, they are at an all-time low. Things don’t bode well in Mexico, which has a double-whammy of rising corn costs for tortillas (thanks to our subsidies and ethanol policies), more people sneaking BACK into Mexico, with resulting gang warfare – I mean, what jobs really are left down there? Even modern, “safe” Monterrey is sprayed by gangland bullets every day.
In a perfect storm, of course, proposals to erect a wall along the Rio Grand could have the effect of keeping illegal immigrants inside the US. I don’t get it. Housing is tanking, agriculture is taking a tremendous hit, and once again we have that sinking feeling that we got it all wrong.
Thursday, August 09, 2007
The Dog Days of summer set in with a vengeance after a rainy and cool year so far. Lucky us, we at least have a little sea breeze and the temperatures are actually lower than in many other parts of the nation. Today also marks when the hurricane predictions were updated by University of Colorado and NOAA: 13 to 15 named cyclones between now and late October. As Jeff Masters remarked over on his blog at Weather Underground, that’s a bunch considering we only had three fizzlers this year, with Chantal being the last. To add further complexity, the tropics are dead quiet, absolutely nothing.
But as Dr. Masters also said, the conditions are right and two weather models already predict a tropical depression in the Caribbean or Gulf forming by this coming Tuesday – although another two do not. Obviously, it’s the time of year not to be complacent. Conditions are perfect right now.
The surfers bemoan the lack of waves and wish for something to happen way offshore to send us some decent swell. They even invented a game called surfboard polo, they are so bored – doesn’t that sound wacky? In the meantime, I’m making sure the fish in the skinny surf are as well fed as possible by fishing with barbless hooks. It’s quite an art, although I think the brown surf crabs are getting more than their fair share.
Theories abound as to why ennui and extreme danger can coexist at once, on these hot subtropical days. One is that all the politicians and the President take off August and bring their hot air back to their constituents, instead of leaving it up in D.C. You’ve heard the old hat that a butterfly in Africa could beat its wings to create a slight downdraft, which turns into a thunderstorm and then a hurricane. I beg to differ: it’s all that bellowing by politicians that creates a “giant sucking sound.”
Inside joke, a cyclone has very low pressure and by definition, sucks air. As my mind wanders, no doubt fueled by lack of big contracts to work on this week, I recall a meeting of several days ago with Town management about bay issues. During casual conversation Raul Morales mentioned that most of the buildings on this Island were substandard because they did not have blow-through walls on the first story, in case a hurricane came along – either that or they needed at least three rebar rods in cement block walls as opposed to one every five feet. So I had to mention I had a 1970 beach house on telephone poles and he nodded approvingly. “The force of the water is tremendous, but you just let it go and you will be safe. Did your house sway very much?”
Laughing, I said the house was bucking and snorting like a mustang but nary a crack in the tile floor or sheetrock walls, even in an estimated 86 MPH gust. Not that I’d want to ride that rodeo again.
Monday, August 06, 2007
Account Opened for Rebeccah Morrison
You may have missed Rebeccah Morrison’s friendly hello when entering the
Recently, she suffered a serious illness and as a result has been absent from work. To help off set medical costs, an account has been opened in her name. Those desiring to make a monetary contribution can do so at the following bank:
First National Bank of
Rebeccah H. Morrison
Account # 626-538
(Rebeccah is the Receptionist/Secretary at City Hall)
Saturday, August 04, 2007
Being a Gemini helps, I guess, being an air sign. I love watching the clouds especially in the summer, especially if they form thunderheads like this one off Boca Chica, the shoreline between South Padre Island and the Rio Grande at Mexico. Nothing dramatic as you can see, but there was an anvil and some heavy rain to the south – we got a few drops here. Summer sea-breeze showers are notoriously short-lived and local.
But to me it is power. The amount of energy expended in a 15-minute thunderstorm burst could well be similar to a nuclear bomb. Can you imagine is we could harvest that power, including the static electricity that causes the lightning? Did you know that lightning can heat the air into a state called “plasma” which is as hot as the sun? Anyway, that hot, expanding plasma is what makes the sound of thunder.
No water spouts today, which I’ve rarely seen here but more common in Florida and the Bahamas. One thunderhead blossomed over the mainland, possibly Los Fresnos, and became a meso-cumulus storm, or MCS. That means it has lots of big 15-minute storms that converged into one very large party animal. At least there’s some drama, as this time of year we should be hot, dry, and no clouds at all.
Have you’ve visited our island very much? You might have noticed that storms form off the coast, jump right over the island without raining more than ten drops, and then go “kaboom” once one the mainland. I don’t have all the answers but I can say I talked with some ozone modelers up in Austin who said that inland bay systems such as Laguna Madre are quite complex, and can have a profound effect on the weather. Of course, they lost me when they talked about micro-climate stability index, flow reversal, salinity, and the Ricardo Effect.
Hey, I’m just a silly old air sign!
Thursday, August 02, 2007
As I sit here, pondering still upon the vagaries of mankind and local politics, I am reminded of two things. First, how lucky we are. That’s a borrowed Flickr ™ picture of Amazing Walter with the caption “I’m the Lucky Man.” I have to feel good inside just seeing that beautiful water and a true smile. It is true, for all the stories, threats of immanent destruction, and disaster, we are truly blessed – very lucky indeed.
The other thing I was contemplating was a huge pile of cardboard boxes containing my new desktop computer. This old dog-of-a-Dell has made it almost five years, an incredibly long time with life in the fast lane. If you knew how much money I made off this old clunker – all honest and no hacking - you’d probably want to steal it. Gosh, I can’t even think to remember all the passwords and accounts I have all over the world. But alas, it has taken to turning itself off and going to sleep whenever it wants, just like an old dog.
Thank goodness it doesn’t need to go outside to pooh.
But maybe with a new email address I can just start over again like a
As you may have caught in some recent postings, I’ve pretty much downplayed the political stuff, mainly on account I’m going into my second childhood and children don’t need no stinking politics. I want to learn, grow, and ask innocent questions. I want to see people smile and look deep into blue-green water. I consider myself to be a very lucky man, too.