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Exploiting Tomorrow's Solar Eclipse To Help Understand Sea Levels

mdsolar writes "Tomorrow at dawn on the U.S. East Coast, a partial solar eclipse will rise. Solar eclipses have many uses. They can confirm the Theory of Relativity, allow study of the solar corona, and this week, help prepare for global warming induced sea level rise. The tides induced in the oceans when the Sun and Moon are aligned are particularly high (and low) and give a foretaste of the effects of sea level rise in the coming decades. Maryland's Department of Natural Resources is asking for photos of these King Tides to help with preparation for the effect of sea level rise. Way to get out front, Maryland."

26 of 92 comments (clear)

  1. Yes, it is. by Okian+Warrior · · Score: 2, Informative

    To "get in front of a problem" is slang, meaning to take steps to mitigate a predicted problem before it happens.

    I've only heard it in use recently, so it's probably a recent addition. It's the "ounce of prevention" that is worth the "pound of cure".

    (With gratitude to all the UK people who take the time to explain British slang. :-)

    1. Re:Yes, it is. by Moridineas · · Score: 3, Informative

      I'm American and I've definitely heard "get in front of a problem" but I've never heard it shortened to just "get out front" as it was in the story (nor removed from context as it was). I was confused as well. Perhaps the submitter was just being idiosyncratic.

    2. Re:Yes, it is. by Moridineas · · Score: 2

      Ounces and pounds are still in common usage in the UK (the country that the GP referred to!). Don't let that stand in the way of an opportunity for you to try to attack the US though. We appreciate your fresh take on the metric system!

  2. I'm Going To Use It by Greyfox · · Score: 2

    I'm going to use it to convince a primitive culture that my God has eaten the sun and that if they don't worship him and agree to build a pyramid, that they will never see their precious sun again! Muahahahahahahah! I figure I can get that all wrapped up by the time it pops back out again.

    --

    I'm trying to teach myself to set people on fire with my mind... Is it hot in here?

  3. Re:Nice, but.... by gmuslera · · Score: 3, Insightful

    Math is nice, let you build models, make predictions and so on, but it could describe anything possible or impossible in any potential universe, To be sure that it fits in our universe, you must contrast it with reality. Einstein's theory was a bunch of complex equations, but was matching those equations predictions with reality that gave them validity.

    In this particular case, observing it could tell that our guesses had some ground, or that were more or less severe of what is really happening, because maybe some factors we aren't measuring or aren't fully understood yet.

  4. Re:Nice, but.... by Mitchell314 · · Score: 2

    Mathematical models is like software, in that in theory they work great, but in practice the fail many times, in many unexpected ways. Also, complex models require real data to calibrate. ie there tend to be many parameters that we need results to find their specific values.

    --
    I read TFA and all I got was this lousy cookie
  5. Re:Nice, but.... by symbolset · · Score: 5, Funny

    We really need to get to the root of how antropogenic climate change is causing solar eclipses. If this keeps happening eventually the moon will come between the Earth and the sun permanently, leading to an eternal night cursed with ever increasing temperatures. Crops will simultaneously wilt and catch fire. With the right global publicity board report we should be able to get a bunch of powerless scientists to achieve a high degree of consensus about the subject, and then do nothing.

    --
    Help stamp out iliturcy.
  6. Re:USA Today by Fwipp · · Score: 3, Funny

    Dang, where are you at? NoScript only passed partially in front of the logo in my area. You're really lucky to see the full eclipse!

  7. Eclipse not needed by Geoffrey.landis · · Score: 4, Informative

    This is cute, but the difference in tidal forces between an eclipse and any other full moon is not very much-- the moon and sun are still pretty closely lined up. If it's within a few months of an eclipse, the difference is trivial. Or, for that matter, a lunar eclipse would also be as good.
    Next month's full moon will have (very slightly) higher tides-- the Earth is a month closer to perihelion.

    --
    http://www.geoffreylandis.com
    1. Re:Eclipse not needed by Mt._Honkey · · Score: 2

      New moons and full moons have essentially the same tides, because the tidal force is quadrupolar.

      --

      Don't Bogart the fish sticks
    2. Re:Eclipse not needed by Will.Woodhull · · Score: 4, Informative

      I don't think parent post is quite right.

      The spring tide of an eclipse day is probably not significantly higher than any other spring tide when all other things are equal. But the existence of perigee and perihelion means that other things may not be equal.

      This particular eclipse happens near perigee, as the Moon nears its closest approach to the Earth. This does make for a king tide, a high tide that is significantly higher than other spring tides. Also the Earth is coming up on perihelion in a few weeks, as parent post states, when it is at its closest approach to the Sun. That will also push the tide higher.

      Additionally, Maryland is positioned relative to the line of the eclipse such that the tidal bulge will be higher at Maryland's shores than at, say New York or Georgia, that are at roughly the same longitude.

      --
      Will
    3. Re:Eclipse not needed by Will.Woodhull · · Score: 3, Funny

      But full moon eclipses are quite rare. Granted they can be devastating and in fact indicate severe climate and geologic upheavals.

      --
      Will
    4. Re:Eclipse not needed by gnasher719 · · Score: 2

      New moons and full moons have essentially the same tides, because the tidal force is quadrupolar.

      You are wrong. At new moon, moon and sun are almost in a straight line, so the force of moon and sun are added up. At full moon, moon and sun are in opposite directions, so their forces subtract.

      The lovely image that your link shows demonstrates that there is a tide at the side pointing to the moon, and on the other side. Totally true, that's why we have high tide every twelve hours. Still, the side pointing to the moon has a slightly higher tide because it is closer. And a big influence is that the moon doesn't go in a circle around earth, but in ellipse.

      So the highest tide happens when the moon on its ellipsoidal path around earth is closest to the earth, on the side that points to the moon, if it coincides with a new moon.

    5. Re:Eclipse not needed by Deadstick · · Score: 2

      At new moon, moon and sun are almost in a straight line, so the force of moon and sun are added up. At full moon, moon and sun are in opposite directions, so their forces subtract.

      No. Tidal forces come from the gravity gradient, not the gravity magnitude, and the gradient works both ways. If the Earth and Moon orbits were exactly circular and coplanar, full moon and new moon tides would be the same.

      Lunar tides are larger than solar tides because, yes, the moon is closer, so its gravity gradient is larger even though the magnitude of its gravitational force is smaller. We have lunar tides because the side of Earth away from the moon is 0.034% farther from the Moon than the near side; we have solar tides because the dark side of Earth is 0.0068% farther away from the Sun than the light side.

      The largest possible tide will occur if Earth is at perihelion, the Moon is at perigee, and the Moon is on the Earth-Sun line, on either side of Earth -- a pretty rare occurrence.

  8. Surfin Safari by flyneye · · Score: 2

    Oh don't think of it as man induce global warming, so much as, ever changing real estate values in the evolution of a planet.
    I confess, It's my fault. In order to bring surf tourism to Kansas, I've calculated the precise amount of beans fed to cattle to produce the correct results.
    Call me a nut, but I farm beans and raise cattle and manufacture my "special feed" sold at cost around the state. It is a Holy thing to bring the masses to the rental property.I cite the "Surfi-ism" lectures by St. Lex of the Luthoran Church. " Upon this rock, I build my church", the rock of course, being Kryptonite.
    Stay tuned for more puzzling evidence.

    --
    *Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
    1. Re:Surfin Safari by flyneye · · Score: 2

      Take into account all the pissing going on with environmentalists, recalculate.

      --
      *Repent!Quit Your Job!Slack Off!The World Ends Tomorrow and You May Die!
  9. Let me get this straight by reboot246 · · Score: 2

    The sun and/or moon in their various cycles can effect the tides on Earth, but they have no effect on changes in the climate?

  10. Prior Art by SuperKendall · · Score: 2

    I'm going to use it to convince a primitive culture that my God has eaten the sun

    So just like AGW, only convincing people to give you money directly to save them from the doom you insist is real, instead of proxying funds through the government first.

    It's always good to cut out the middle man.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  11. Eclipse as Propoganda by SuperKendall · · Score: 4, Informative

    Nothing like using an unusually high tide to scare people about global warming, even though ocean levels are now predicted to rise something like 4" over 100 years (NOT four feet as the government website sadly parrots) ... the variance of a good spring tide can be more than that.

    It's just really sad to see people conned in the name of science.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
    1. Re:Eclipse as Propoganda by rrohbeck · · Score: 2

      4"? Where does that nonsense come from?

    2. Re:Eclipse as Propoganda by bunratty · · Score: 2

      According to the EPA, sea level rise is predicted to be 30 to 70 inches over the next 100 years. That sounds much closer to all the other estimates I have heard. That sea level rise is enough to cause hundreds of millions of people and the corresponding infrastructure to relocate. And there's no reason that the sea level will magically stop rising after 100 years. It'll keep rising unless we can somehow scrub the excess CO2 out of the atmosphere.

      --
      What a fool believes, he sees, no wise man has the power to reason away.
    3. Re:Eclipse as Propoganda by SuperKendall · · Score: 2

      The IPCC. Keep reading the other replies to my post for the informative AC response that includes a link, rather than your contentless fear-mongering.

      The EPA report someone else links to was from the older study before the IPCC realized they'd been had. Sorry you have not come to the same realization yet.

      The question you have to ask yourself is, are you truly capable of making an informed decision based on real facts? Or are you going to allow yourself to be led by insular opinions that agree with your preconceptions forever?

      --
      "There is more worth loving than we have strength to love." - Brian Jay Stanley
    4. Re:Eclipse as Propoganda by Layzej · · Score: 2

      Modded troll? Really?

  12. Re:Nice, but.... by dov_0 · · Score: 2

    Talking of math and science in general, this idea isn't related to either. What the hell are pictures and videos of a single king tide going to tell us about about anything EXCEPT the level of that single king tide. There simply isn't enough data to show anything. No real measurements, no real data.

    --
    sudo mount --milk --sugar /cup/tea /mouth /etc/init.d/relax start
  13. Re:Nice, but.... by Attila+Dimedici · · Score: 2

    It will tell us how the incoming water distributes as it comes in. There are some non-intuitive ways that the flow of incoming water reacts to obstacles and other features of the land (such as low points) as a result of fluid dynamics. While our understanding of fluid dynamics can explain what happens, the complexity of the interactions with a rising tide make it impractical to fully catalog those effects in advance. The data that can be gleaned from these pictures will be useful for dealing with storm surge issues as well.

    --
    The truth is that all men having power ought to be mistrusted. James Madison
  14. Re:Reference for the 4" by Layzej · · Score: 2

    There is no evidence that the rate of sea level rise is increasing

    No evidence except for the measurements and data. Here's a graph from NOAA.

    Sea level rose rapidly 10,000 years ago at the end of the last glacial period. They have been fairly stable for the last 8000 years until levels began to climb again in the 20th century.

    Records and research show that sea level has been steadily rising at a rate of 1 to 2.5 millimeters (0.04 to 0.1 inches) per year since 1900.

    Since 1992, new methods of satellite altimetry indicate a rate of rise of 3 millimeters (0.12 inches) per year. - See http://oceanservice.noaa.gov/facts/sealevel.html