Sunday, October 18, 2009

It's not simply global warming... IT's CLIMATE CHANGE

Does Earth's climate system have an 'Achilles' heel'?

Here is a simplified description of some basic ocean-atmosphere dynamics that regulate Earth’s climate:

The equatorial sun warms the ocean surface and enhances evaporation in the tropics. This leaves the tropical ocean saltier. The Gulf Stream, a limb of the Ocean Conveyor, carries an enormous volume of heat-laden, salty water up the East Coast of the United States, and then northeast toward Europe.

Two views of the Gulf Stream

The global ocean is not a static pond, but a body in constant motion. Winds blow across its surface, generating waves and currents, while the pull of gravity gently sloshes it back and forth in a lunar rhythm of tides. But beneath these familiar surface motions is a seemingly mysterious process which has major implications for Earth's climate: the Great Ocean Conveyor (also called the thermohaline circulation).

The Conveyor is one of the great unknowns in humanity's unintentional climate change experiment. Surface water, warmed at the equator, moves to high latitudes where it releases heat to the atmosphere. As a result, the water cools - becoming denser - and sinks to the deep ocean. Deep water slowly travels through the oceanic abyss, eventually mixing up to the surface in distant parts the world, as much as 1000 years later.

This oceanic heat pump, is an all important mechanism for reducing equator-to-pole temperature differences. It moderates Earth’s climate, particularly in the North Atlantic region. Conveyor circulation increases the northward transport of warmer waters in the Gulf Stream by about 50 percent. At colder northern latitudes, the ocean releases this heat to the atmosphere—especially in winter when the atmosphere is colder than the ocean. The Conveyor warms North Atlantic regions by as much as 5° Celsius and significantly moderates average winter temperatures.

The transfer of energy, heat, by the great Ocean Conveyor is what lets Norway, which is as far north as Manitoba Canada have annual temperatures 20 degrees warmer. If not for the North Atlantic loop of the Conveyor, European winters would be much colder. London would be like Laborador, Berlin might have the climate of Edmonton Alberta, which lies at the same latitude, while Stockholm might be more like Nome, Alaska.

(CBS/AP) OCT 16, 2009
The North Pole will turn into an open sea during summer within a decade, according to data released by a team of explorers who trekked through the Arctic for three months.

NBC Nightly News Channel - Oct. 15, 2009
The Arctic Ocean will be an "open sea" almost entirely free from ice within just t
en years. Ice over during the summer months will have entirely disappeared within 20 years, but most of the decrease will happen before 2020.

So Santa needs a new home ... What else?

Unfortunately it may get even more confusing...

More like

Out of the frying pan and in to the freezer ?

In 2005 Nature , published the results of a study showing that the Gulf Stream current (the one that keeps Europe warm despite the fact that the UK is as far north as Hudson Bay) has slowed down by about 30% since 1957. The study noted that the slowing has mostly happened in the years since 1998.

Further studies indicate that during that time due to all the fresh water runoff from melting ice, North Atlantic waters have become steadily less salty in the places where cold, salty water is supposed to sink, starting the Great Conveyor. Fresher water is less dense than ocean water and does not sink as readily. The Great Conveyor is slowing down.

Records and evidence of past climates—from deep-sea sediments and ice-sheet cores—show that the Conveyor has slowed and shut down several times in the distant past. This shutdown stopped the heat transfer to the North Atlantic and brought about colder climates and mini -Ice Ages. One earth scientist has called the Conveyor “the Achilles’ heel of our climate system.” (Gagosian, Robert B. Woods Hole Oceanographic Institution updatedSeptember 3, 2009)

Something is throwing the climate out of balance. Computer models and scientists agree that it appears to be human activity and increased greenhouse gasses. The warming and freshening (i.e. reduced saltiness) in the northern North Atlantic ocean predicts a slowing or even a complete stop of the North Atlantic currents - just like the sudden cooling in the past, thousands of years ago.

This could be disastrous for eastern North America and western Europe. Average temperatures could plunge by 5 degrees C - for comparison, this is about the same difference as between the global average temperature today and during the last Ice Age, when Canada lay beneath 3000m thick glaciers. (David Suzuki Foundation, 2009)


The Comments Box is open..

What do you think?

How can people help change what could happen?

What more would you like to learn?


  1. (this a comment on the hulu video)
    that is weird how were affecting the earth this much to turn all that ice to water, I feel sorry for all those polar bears out there.

    Aby p.2 (orange)

  2. this blog is cool and so were the videos on it

  3. poor polar bears i will help the north pole (or try to help) so i will help by:the car when getting fast food and other stuff.

  4. Omg i almost cried from rhat picture of the polar bear If u think about it All of the polar bears will eventually die in 10 years or so becuase they wil drown
    Ada h green

  5. I enjoyed the videos

  6. I am amazed that the currents can actualy stop! I find it ironic that if climate change, or "Global Warming", continues, then there will be another ice age. I would like to know more about the data that the researchers found in order to predict that the polar caps will melt in 10~30 years.

    Christopher Tepetitlan BLUE class Period 5

  7. that picture with the polar bear made me feel very sad because I LOVE animals and it pains me that their home will be gone within a decade. I think that the animals in the north pole are very magnificant and I will try my hardest to help them! I will start walking wherever and whenever I can.
    Taylor Boyd-Blue

  8. Today i parked and went into Burger King, it was alot faster, it is so amzaing that no ice would cuase so many issues and don't forget those polar bears

    >.> Polar Bears are awesome<.< Also my classmates even though it may not seem like much but, just park and go in!!

    I finally firgured out how we think?!

    We think, "WOW, parking isn't going to do anything if its just me!" But you also might set an example for other people to follow, and alot more people go in than you think, and you just do your little part of reclying, parking, and trying to conserve water and we won't have to worry about an ICE AGE!!!!


    Michael S., Blue

  9. i dont get mr v how will the gulf stream stop if the north pole melts????????i aalso i feel bad for the polar bears too:/

  10. All that FRESH water will change the "salinity" and the water won't sink to the deep benthic regions to keep the Great Conveyor going.

    That's what the past geologic records tell us... It's not too late to change the future.. we just have to start and do our part today.

  11. i hope that people will start recycling more and we can save the polar bears and the north pole.

    Aby p.2(orange)

  12. i will do my part mr.v or try to do my part. i will miss the polar bears if the go bye bye

  13. I hope so too Aby. That's why I am trying to get as many kids to help as possible. Only working together can we solve the really BIG problems.

  14. The pic. of that polar bear is really sad because i blame myself and other humans for glabal warming.I think we should make an organization at school and get some supporters to help out and try to spread the word about global warming. What do you think Mr.V?

    Rachel orange

  15. We are doing that with posters and projects. YOu will make a poster about your issue. If you want to start an organization / club we can do that to... a great idea actually.

  16. i feel terrible about that polar bear on that small block of ice.what can we do to save the polar bears?!!!

    megan kronsperger, p.3, yellow

  17. my comment is about that video about the ocean conveyor belt it makes the lionfish invasion make more sense [to me at least]

    Kaitlyn class-violet

  18. Its really scary what we are doing to this Earth... And the whole polar ice berg melt down thing is seriously scary since the polar ice bergs keep some of the UV rays out. :(

  19. Wait a minute, if the global conveyer belt would take 1,000 years to complete one cycle, how long would it take now that it is slowing!?!?!?!

    Ryan McGahan
    yellow class
    6:44 P.M

  20. Have you shared this information with other Science teachers, Mr. V? I think they would be quite interested in this. Mabye will tell THEIR students about it! Then, there will just be more people to promote stopping Global Warming!

    Ryan McGahan
    yellow class
    6:50 P.M

  21. A good question Ryan. Perhaps you could be the scientist to study this question.

  22. Why won't someone do something about it? I think it can be fixed.
    Derrick T., Red

  23. I would like to learn more about how the Earth will be affected if the poles melt. How could we prepare for it?

  24. YOu can do something about it.... think green and decrease green house gas emissions... walk if you can, bike if you can, reduce fossil fuel use, reuse and recycle.

  25. Um...Mr.V i dont rember what that cool song that you taught us today HELP!!!!!!!! The starting letters for each word is... K,P,C,O,F,G,S HELP!!!!

  26. Savannah .......

    it is called taxonomy .......

    kingdom, phylum, class, order, family, genus, species

    MR V

  27. I wonder how the higher salt content in the tropical ocean waters affect the animals that live there [if at all they might just adapt to it]Kaitlyn violet