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            A preface is needed, to establish the term “king tide” as used in this Fact #6. Every year, most oceanic coastlines (this eliminates things like The Great Lakes, and the Mediterranean Sea) will experience 3 or 4 extra-large, extra-high tidal surges. Those tides are called “King Tides”.

            No one needs to know, memorize, or remember WHY a few specific high tides, each year, are higher than any others; however, for those who find such things interesting, and who want to know more about what is really happening, here is a brief explanation, which can be skipped by anyone who does not want this level of detail.



            King tides (i.e., two or three high tides, each year, which are higher than any other high tides all year long) are caused by a combination of three factors: (i) the alignment of the moon and the sun, on the day or night of a king tide; (ii) the moon will be as close to the earth, as the moon gets, in its orbit; and, (iii) warming and expansion of the ocean water near that coastline, which occurs every summer (in different months, in the northern and southern hemispheres).

            All orbits are elliptical, rather than perfect circles, and the moon’s distance from the earth ranges from less than 222 thousand miles (the `perigee’) to more than 252 thousand miles (the `apogee’). Both of those points are reached every time the moon orbits the earth, which takes 27.3 days when measured against distant stars, and 29.5 days when measured against an imaginary line passing through the center of the sun and the center of the earth. Since that imaginary line travels all the way around the sun every year, the moon must always “chase” it, so the “synodic” orbit (29.5 days) takes longer than the “sidereal” orbit (27.3 days). Most people don’t want to have to remember or deal with details like that, so we usually refer to 28 days, as a compromise.

            And, the power of a gravitational pull depends up on the distance that separates two objects, SQUARED (i.e., to the second power; the distance at any moment in time must be multiplied by itself, in the equation used to calculate gravity). Therefore, when the moon gets 10% percent closer to the earth, its gravitational pull becomes more than 20% stronger (i.e., 1.1 x 1.1 = 1.21), compared to its lowest level of gravitational pull, when it is most distant.

            So, roughly once each month, the sun, moon and earth line up in a certain way, AND, the moon reaches one of its closest points, in its elliptical pathway around the earth.

            The third major factor, which also must occur for a `king tide’ to occur, involves summertime warming of the ocean next to a particular coast. For example, the Eastern (Atlantic) coast of America is affected by something called `the Bermuda High’, which occurs every summer, but then moves south, as autumn progresses. That factor causes king tides to occur later, in Florida, than in coastal states farther north.

            Although king tides occur on west-facing and south-facing coastlines, they are not as bad, along those coastlines, as on coastlines which face east. Tides are created mainly by the pull of the moon, and therefore, they follow the moon. Since the moon rises in the east, and then appears to travel west (as the earth rotates), tides move in the same direction (from east, to west). Therefore, west-moving “approaching tides” hit our eastern coastline, on the Atlantic, with momentum and inertia they build up while crossing the Atlantic. By contrast, when the moon passes over America’s west-facing Pacific coastline, its gravity can only begin pulling on water that is already sitting next to that west-facing coast. That does not allow the water to build up the type of momentum that would push even more water up against that coastline. Similarly, places like New Orleans and Houston, on the northern edge of the Gulf of Mexico, also have king tides, but they are not as strong (compared to normal high tides) as they are along the Atlantic coast.

            None of the above needs to be remembered (or even known) by anyone who wants to ask a candidate for Congress (or a climate change denier) a pointed question about the undeniable problems described below, which are getting worse every year, and which have now begun to get even worse, even faster.  


            In southern Florida, numerous neighborhoods in and around Miami initially were built on what was, at the time, reliably and constantly dry ground (except when it was raining), even during king tides. Some people might try to quibble with that claim, but it is just basic straight-forward common sense and history; it pretty much had to be that way, when any such neighborhood was being built, in order to sell the homes, shops, and other buildings in those neighborhoods.

            However, during the decades since those neighborhoods were initially built, sea levels have risen, to a point where, during “king tides” (which – as noted above – occur several times, predictably and reliably, each and every year), salt water will flood the streets of those neighborhoods – to a point where it will now rise up over the ankles of anyone standing on one of the affected streets, in large and growing numbers of those neighborhoods. If anyone doubts that assertion, do a quick internet search to combine “Miami” with “king tide”. If you do, you will find that, among other things, the Miami newspapers announce, in advance, what days the king tides will occur, and on those days, things like special parking laws and permits take effect.

            Or if, for some reason, you don’t like Miami, or if you think it is being singled out unfairly, combine “king tide” with Annapolis, or Boston, or any other city on the Atlantic coast; or, just combine “king tides” with “Atlantic”, in a search. A good summary for laypersons is a Washington Post article entitled, `King tides, boosted by sea-level rise, are flooding communities along the East Coast’. It is available at

            So . . . although the several-times-every-year flooding problems caused by “king tides” rarely get attention outside the cities affected by them, the undeniable fact is that America has reached a point where sea level rise is already causing serious flooding, and flood damage, repeatedly, every year, all along the Atlantic coast. And, anyone who knows what is happening, and why, can predict – not just with confidence, but with total certainty – that those problems will grow larger, and more damaging, in the coming decades. That prediction can be made with the same level of certainty as a prediction that if someone throws something heavy up into the air, on any day next week, it will come down again . . . on that very same day!

            The people who wrote this website hereby propose that any member of Congress who votes against measures to limit global warming, should be required to take a bus-ride to Annapolis (which is only about 30 miles from D.C.), on a day when a king tide is predicted, and they should be required to stand on one of its coastal streets, while that tide peaks. And, while doing so, they should be required to wear their best, fanciest, most beautiful and expensive shoes.

            Or, as an alternative, perhaps members of Congress who actually want to help control global warming, should take that trip, voluntarily, with TV cameras along for the ride. And, if they do that, they should get to wear any shoes or sandals they choose.

            The point that needs to be made, is this: it will NOT help change the outcomes of any elections, in ways which might help send more “climate literates” to Congress, if people try to argue about millimeters. Why not? Two reasons:

            (i) Because millimeters are just too dang small, in the minds of nearly all voters; and,

            (ii) most voters in America are far more used to, and comfortable with the “English” system of measurements (feet, inches, yards, miles, etc.), than the metric system; and, therefore, they tend to become resentful, and they start feeling like someone has shifted into a condescending mode, if that person begins trying to lecture them with (or about) metric numbers.

            What would help, instead, is if national news outlets begin showing pictures – several times, every year, choosing the maximum tide dates for each of several cities along the Atlantic – which will show people standing in a salt water flood, up to their ankles, not because of any rain nearby, but because of a normal, regular, and predictable tide which will indeed happen, in each and every affected city, several times each year, every year, from now on, for all time into the future.

            As another brief aside about metric measurements, climate advocates should stop referring to degrees CELSIUS, when talking about weather or climate temperatures. Instead, we should make a concerted effort to change the “Fahrenheit” scale of temperatures, into a better phrase, such as “the weather scale”. Fahrenheit was a German scientist and artisan, who made the first mercury-in-glass thermometers that were good enough to be consistent, and reproducible. Although there are conflicting versions of the exact series of steps he used to create his temperature scale, a widely-accepted version is that, when he had reached a level of quality he was comfortable with, he took his thermometers, hung them outside, and made a mark on the backing boards which supported and held the glass-tube thermometers, showing the highest temperature that the air (in the shade) reached, on a hot day in his town (which was Danzig, Germany, at the time; it is now Gdansk, Poland). He apparently tried to do the same thing, to also mark the lowest temperature that was reached during the winter, but that attempt became so arduous, painful, and inconvenient that he shifted his focus, and began experimenting with mixtures of brine (i.e. water with at least as much salt as sea water, and often more), ice, and ammonium chloride (a different type of salt, which could depress the freezing point of water even more, to a point where it approximated the coldest temperatures he previously had measured outside, on the coldest days of the year). He then set THAT temperature as the zero point, in his scale.

            As a result, Fahrenheit created a very good, very functional, and readily understandable (by pretty much anyone) WEATHER scale. Every American knows – to a point where it is almost instinctive by now, and needs no explanation – that when it gets to be 100 degrees – which does indeed happen in the U.S., quite commonly, in lots of places, during the summer – then it is so darn hot outside that it is dangerous to go out into that kind of heat, except to go swimming, or play in the sprinkler.

          And, every American also knows, almost instinctively, that when it gets down to zero degrees – which does indeed happen in the US, in lots of places, during the winter – then it is pretty darn cold, and one had better be dressed in not just one but several layers, if they go outside.

            By contrast, most American voters just get fed up, and disgusted, with having to do mental calculations, to try to convert . . . umm . . . well . . . is it degrees CELSIUS? Or, is it degrees CENTIGRADE? Most American voters do not know or remember even THAT. So, they find that whole mess confusing, and irritating. They will respond better, to speakers and candidates who talk about temperatures in the Fahrenheit scale. And, they would respond even better than that, if we could somehow shift that name over to something like, “the weather scale”, which accurately reflects how and why it was created, and what it does best.

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