why is the tide so high today
We all know the moon is primarily responsible for the rising and falling of ocean tides. In most places, but not everywhere, there are two high tides and two low tides a day. For any particular spot on Earth s surface, the height of the tides and their fluctuation in time depends not only on the moon, but also on the sun and also on the shape of the specific beach, the larger coastline, the angle of the seabed leading up to land, and the prevailing ocean currents and winds. The difference in height between high and low waters varies as the moon waxes and wanes from new to full and back to new again. The larger tides are called
spring tides (nothing to do with season of spring). The smaller tides are called neap tides. Click the links below to learn more about the tides. What are spring tides? Around each new moon and full moon, the sun, Earth, and moon arrange themselves more or less along a line in space. Then the pull on the tides increases, because the gravity of the sun reinforces the moonБs gravity. In fact, the height of the average solar tide is about 50% the average lunar tide. Thus, at new moon or full moon, the tideБs range is at its maximum. This is the spring tide: the highest (and lowest) tide. Spring tides are not named for the season. This is spring in the sense of jump, burst forth, rise. So spring tides bring the most extreme high and low tides every month, and they happen around full and new moon. What are perigean spring tides? When the new moon or full moon closely aligns with perigee closest point to Earth in the moon s orbit then we have an extra-large. For example, in the year 2016, the April 7 new moon will closely align with perigee and the November 14 full moon will closely coincide with perigee, to bring forth perigean spring tides. It s when a spring tide coincides with a time of heavy winds and rain flooding due to a weather extreme that the most extreme flooding occurs. What are neap tides? These sorts of tides occur halfway between each new and full moon Б at the first quarter and last quarter moon phase Б when the sun and moon are at right angles as seen from Earth. Then the sunБs gravity is working against the gravity of the moon, as the moon pulls on the sea. This is the neap tide: the tideБs range is at its minimum. Neap tides happen approximately twice a month, once around first quarter moon and once around last quarter moon. There s about a seven-day interval between spring tides and neap tides. Why are there two high tides and two low tides each day? If the moon is primarily responsible for the tides, why are there two high tides and two low tides each day in most places, for example, the U. S. eastern seaboard? It seems as if there should just be one. If you picture the part of Earth closest to the moon, it s easy to see that the ocean is drawn toward the moon. That s because gravity depends in part on how close two objects are.
But then why on the opposite side of Earth is there another tidal bulge, in the direction opposite the moon? It seems counterintuitive, until you realize that this second bulge happens at the part of Earth where the moon s gravity is pulling the least. Earth spins once every 24 hours. So a given location on Earth will pass БthroughБ both bulges of water each day. Of course, the bulges don t stay fixed in time. They move at the slow rate of about 13. 1 degrees per day Б the same rate as the monthly motion of the moon relative to the stars. Other factors, including the shape of coastlines, etc. , also influence the time of the tides, which is why people who live near coastlines like to have. Coastal areas in eastern North America and the United Kingdom and no doubt elsewhere around the world are experiencing exceptionally high tides this week, caused by Sunday s supermoon. Although the tides should not be as high on Wednesday as they were on Monday and Tuesday of this week, heavy rains from Tropical Storm Joaquin, now in the western Atlantic, may combine with the tides to create a flood threat in the U. S. East. Astronomers who understand supermoons, which they call perigean full moons, had been expecting higher-than-usual tides. It s not just a supermoon, though, causing the extra-high tides this time. The effect on the tides is being accentuated by the fact that we re near the peak of an 18-6-year cycle of the moon, which features what astronomers call a minor lunar standstill. Follow the links below to learn more. Extremely heavy rain combined w/ windy conditions record high tides from, flooding is likely in many coastal areas (cont) Maritime Wx Agency (@maritimeweather) Flooding due to high tide on Miami Beach along Indian Creek Road at 30th street. Emily Michot (@EmilyMichot) Monday and Tuesday s high tides in North America. The Miami Herald posted a on Tuesday showing they call in Florida a king tide. This extra high tides known as a perigean spring tide to scientists hit Miami Beach on Sunday and Monday (September 27 and 28, 2015). Higher-than-usual tides flooded parts of South Florida, and other parts of the state. North Carolina beaches were stormy this past weekend, and flooding hit particularly hard at North Topsail Beach. South Carolina s high tides can be seen in the photos below. People were also talking about the extra-high tides further up the U. S. East coast, while bracing for heavy rains from Tropical Storm Joaquin. The rainfall forecast for the coming week shows heavy rain across the U. S. Mid-Atlantic and Northeast, mainly from Tropical Storm Joaquin interacting with a stalled front. Potential flooding will depend on the storm track, the amount of rain and, in some places, the height of the tides. The tide chart below is for Atlantic City, New Jersey. Tidal guidance now pointing to at least 3 consecutive flooding high tides.
Not exactly ideal. StormForce_1 (@StormForce_1) In New Brunswick bordering the U. S. in eastern Canada Tuesday s tides hit a peak that had not been reached in nearly two decades at the Bay of Fundy, which. Bay of Fundy tides of 14. 2 meters (about 50 feet) were expected,. Water water everywhere. Today also marks the highest Bay Of Fundy tides in 20 years. New Brunswick (@SeeNewBrunswick) High tides in the UK. Various media, and, reported high tides in parts of the UK early this week. On Tuesday night, there were 4 flood warnings and 27 alerts in effect in England, and 3 flood warnings and 8 alerts in effect in Wales. A flood warning means that flooding is expected. A flood alert means that flooding is possible. Or follow the UK s flood warnings and alerts via on Twitter, licensed by the UK s Environmental Agency. These kayakers took advantage of high tides with awesome results WalesOnline (@WalesOnline) How does a supermoon affect the tides? All full moons bring larger-than-usual tides, and supermoons called perigean full moons by scientists bring the highest (and lowest) tides of all. The gravity of the sun and moon always combine to create the tides. Consider that each month, on the day of the full moon the moon, Earth and sun are aligned, with Earth in between. This line-up creates wide-ranging tides, known as spring tides. High spring tides climb up especially high, and on the same day low tides plunge especially low. They happen every month. A supermoon is a full moon with something extra. It s a full moon that happens to be at its closest to Earth (perigee) for that particular month. Sunday s full moon reaches its closest point to Earth within an hour of the crest of its full phase. It also underwent an eclipse. The extra-close full moon accentuates these monthly (full moon) spring tides all the more. And that s not all, for this particular supermoon. This year, as part of one of the heavens regular cycles, the sun and moon are positioned over Earth s equator in such a way to accentuate the tides. This pattern which features what s called a minor lunar standstill by astronomers is causing a smaller Harvest Moon effect this year (the recent full moon was the Northern Hemisphere s closest full moon to the autumn equinox and therefore carried the name Harvest Moon). Meanwhile, it s causing a stronger-than-usual pull on the tides. In settled weather, the high spring tides are a curiosity or nuisance, mainly. But watch out for storms, which have a large potential to accentuate high spring tides and cause serious flooding. Bottom line: Sunday s supermoon, combined with an 18. 6-year cycle of the moon, have caused high tides on both sides of the Atlantic this week. There were many flood warnings and alerts in the UK on Tuesday. In eastern North America, Tropical Storm Joaquin might combine with high tides to cause flooding.
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