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The "dead zone" of the Gulf of Mexico

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    Good evening, welcome to New Orleans.
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    I don't know if you knew this,
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    but you are sitting within 15 minutes
    of one of the largest rivers in the world:
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    the Mississippi river.
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    Old Man River, Big Muddy.
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    And it goes as far north
    as the state of Minnesota,
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    as far east as the state of New York,
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    as far west as Montana.
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    And 100 miles from here, river miles,
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    it empties its fresh water and sediments
    into the Gulf of Mexico.
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    That's the end of Geography 101.
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    (Laughter)
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    Now we're going to go
    to what is in that water.
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    Besides the sediment, there are dissolved
    molecules, nitrogen and phosphorus.
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    And those, through a biological process,
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    lead to the formation
    of areas called dead zones.
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    Now, dead zone is a quite ominous word
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    if you're a fish or a crab.
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    (Laughter)
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    Even a little worm in the sediments.
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    Which means that there's not enough oxygen
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    for those animals to survive.
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    So, how does this happen?
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    The nitrogen and the phosphorus
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    stimulate the growth of microscopic plants
    called phytoplankton.
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    And small animals called zooplankton
    eat the phytoplankton,
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    small fish eat the zooplankton,
    large fish eat the small fish
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    and it goes on up into the food web.
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    The problem is that there's just too much
    nitrogen and phosphorus right now,
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    too much phytoplankton
    falling to the bottom
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    and decomposed by bacteria
    that use up the oxygen.
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    That's the biology.
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    Now, you can't see it
    from the surface of the water,
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    you can't see it in satellite images,
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    so how do we know it's there?
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    Well, a trawler can tell you,
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    when she puts her net over the side
    and drags for 20 minutes
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    and comes up empty,
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    that she knows she's in the dead zone.
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    And she has to go somewhere else.
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    But where else do you go
    if this area is 8,000 square miles big?
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    About the size of the state of New Jersey.
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    Well, you either make
    a decision to go further,
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    without much economic return,
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    or go back to the dock.
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    As a scientist, I have access
    to high-tech equipment
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    that we can put over the side
    of the research vessel,
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    and it measures oxygen
    and many more things.
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    We start at the Mississippi River,
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    we crisscross the Gulf of Mexico
    all the way to Texas,
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    and even I sneak into Texas
    every now and then and test their waters.
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    And you can tell by the bottom oxygen --
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    you can draw a map
    of everything that's less than two,
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    which is the magic number
    for when the fish start to leave the area.
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    I also dive in this dead zone.
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    We have oxygen meters
    that we have to deploy offshore
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    that tell us continuous measurements
    of low oxygen or high oxygen.
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    And when you get into the water,
    there's a lot of fish.
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    Tons of fish, all kinds of fish,
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    including my buddy here,
    the barracuda that I saw one day.
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    Everybody else swam this way
    and I went this way with my camera.
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    (Laughter)
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    And then, down at 30 feet
    you start to see fewer fish.
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    And then you get to the bottom.
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    And you don't see any fish.
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    There's no life on the platform,
    there's no life swimming around.
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    And you know you're in the dead zone.
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    So, what's the connection
    between the middle of the United States
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    and the Gulf of Mexico?
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    Well, most of the watershed is farmland.
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    And in particular, corn-soybean rotation.
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    The nitrogen that is put in fertilizers
    and the phosphorus goes on the land
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    and drains off into the Mississippi River
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    and ends up in the Gulf of Mexico.
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    There's three times more
    nitrogen in the water
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    in the Mississippi now,
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    than there was in the 1950s.
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    Three times.
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    And phosphorus has doubled.
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    And what that means is more phytoplankton
    and more sinking sails and lower oxygen.
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    This is not a natural feature of the Gulf;
    it's been caused by human activities.
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    The landscape is not what it used to be.
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    It used to be prairies and forests
    and prairie potholes
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    and duck areas and all kinds of stuff.
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    But not anymore -- it's grow crops.
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    And there are ways that we can address
    this type of agriculture
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    by using less fertilizer,
    maybe precision fertilizing.
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    And trying some sustainable agriculture
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    such as perennial wheatgrass,
    which has much longer roots
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    than the six inches of a corn plant,
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    that can keep the nitrogen on the soil
    and keep the soil from running off.
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    And how do we convince
    our neighbors to the north,
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    maybe 1,000 miles away or more,
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    that their activities are causing problems
    with water quality in the Gulf of Mexico?
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    First of all, we can take them
    to their own backyard.
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    If you want to go swimming
    in Wisconsin in the summer
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    in your favorite watering hole,
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    you might find something like this
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    which looks like spilled green paint
    and smells like it,
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    growing on the surface of the water.
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    This is a toxic blue-green algal bloom
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    and it is not good for you.
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    Similarly, in Lake Erie,
    couple of summers ago
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    there was hundreds of miles
    of this blue-green algae
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    and the city of Toledo, Ohio,
    couldn't use it for their drinking water
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    for several days on end.
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    And if you watch the news,
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    you know that lots of communities
    are having trouble with drinking water.
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    I'm a scientist.
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    I don't know if you could tell that.
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    (Laughter)
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    And I do solid science,
    I publish my results,
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    my colleagues read them,
    I get citations of my work.
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    But I truly believe that, as a scientist,
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    using mostly federal funds
    to do the research,
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    I owe it to the public,
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    to agency heads and congressional people
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    to share my knowledge with them
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    so they can use it,
    hopefully to make better decisions
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    about our environmental policy.
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    (Applause)
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    Thank you.
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    (Applause)
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    One of the ways that I was able to do this
    is I brought in the media.
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    And Joby Warrick
    from the "Washington Post"
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    put this picture in an article
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    on the front page, Sunday morning,
    two inches above the fold.
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    That's a big deal.
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    And Senator John Breaux, from Louisiana,
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    said, "Oh my gosh, that's what they think
    the Gulf of Mexico looks like?"
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    And I said, "Well, you know,
    there's the proof."
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    And we've go to do something about it.
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    At the same time,
    Senator Olympia Snowe from Maine
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    was having trouble with harmful
    algal blooms in the Gulf of Maine.
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    They joined forces -- it was bipartisan --
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    (Laughter)
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    (Applause)
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    And invited me to give
    congressional testimony,
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    and I said, "Oh, all I've done
    is chase crabs around south Texas,
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    I don't know how to do that."
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    (Laughter)
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    But I did it.
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    (Cheers)
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    And eventually, the bill passed.
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    And it was called -- yeah, yay!
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    It was called The Harmful Algal Bloom
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    and Hypoxia Research
    and Control Act of 1998.
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    (Laughter)
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    (Applause)
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    Thank you.
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    Which is why we call it
    the Snowe-Breaux Bill.
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    (Laughter)
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    The other thing is
    that we had a conference in 2001
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    that was put on by
    the National Academy of Sciences
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    that looked at fertilizers,
    nitrogen and poor water quality.
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    Our plenary speaker
    was the former governor
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    of the state of New Jersey.
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    And she ...
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    There was no thinking she wasn't serious
    when she peered at the audience,
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    and I thought,
    "Surely she's looking at me."
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    "You know, I'm really tired
    of this thing being called New Jersey.
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    Pick another state, any state,
    I just don't want to hear it anymore."
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    But she was able to move the action plan
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    across President George H.W. Bush's desk
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    so that we had environmental goals
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    and that we were working to solve them.
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    The Midwest does not feed the world.
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    It feeds a lot of chickens, hogs, cattle
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    and it generates ethanol
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    to put into our gasoline,
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    which is regulated by federal policy.
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    We can do better than this.
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    We need to make decisions
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    that make us less consumptive
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    and reduce our reliance on nitrogen.
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    It's like a carbon footprint.
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    But you can reduce
    your nitrogen footprint.
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    I do it by not eating much meat --
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    I still like a little
    every now and then --
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    not using corn oil,
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    driving a car that I can put
    nonethanol gas in
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    and get better gas mileage.
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    Just things like that
    that can make a difference.
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    So I'm challenging, not just you,
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    but I challenge a lot of people,
    especially in the Midwest --
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    think about how you're treating your land
    and how you can make a difference.
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    So my steps are very small steps.
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    To change the type
    of agriculture in the US
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    is going to be many big steps.
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    And it's going to take political
    and social will for that to happen.
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    But we can do it.
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    I strongly believe
    we can translate the science,
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    bridge it to policy and make
    a difference in our environment.
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    We all want a clean environment.
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    And we can work together to do this
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    so that we no longer have
    these dead zones in the Gulf of Mexico.
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    Thank you.
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    (Applause)
Title:
The "dead zone" of the Gulf of Mexico
Speaker:
Nancy Rabalais
Description:

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Video Language:
English
Team:
closed TED
Project:
TEDTalks
Duration:
12:02

English subtitles

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