[MUSIC]
JOAN CARTAN-HANSEN: HI.
I'M JOAN CARTAN-HANSEN, AND
WELCOME TO SCIENCE TREK THE
WEB SHOW, AND WELCOME TO THE
MK NATURE CENTER.
AND JOINING ME TO ANSWER YOUR
QUESTIONS ABOUT THE OCEANS ARE
DAVID WILKINS, ASSOCIATE
PROFESSOR OF GEOSCIENCES AT
BOISE STATE UNIVERSITY, AND
WALTER SNYDER, PROFESSOR
EMERITUS, FROM THE DEPARTMENT
OF GEOSCIENCES AT BOISE STATE
UNIVERSITY.
THANK YOU BOTH FOR BEING HERE.
DAVID WILKINS: GREAT TO BE
HERE.
WALTER SNYDER: THANKS FOR
HAVING US.
CARTAN-HANSEN: OKAY.
LET'S GO TO YOUR QUESTIONS.
[MUSIC]
JB: HI.
MY NAME IS JB, AND I GO TO
RIVERSIDE ELEMENTARY SCHOOL,
AND MY QUESTION IS, WHY IS THE
OCEAN BLUE?
SNYDER: WELL, THE OCEAN -- THE
OCEAN IS BLUE NOT FOR THE
REASON YOU MIGHT THINK.
IT IS NOT DUE TO THE FACT THAT
IT'S JUST REFLECTING THE COLOR
OF THE ALREADY BLUE SKY.
THAT'S WHAT MOST PEOPLE WOULD
THINK.
WHAT IT'S REALLY DUE TO IS THE
WAY THE OCEAN ABSORBS CERTAIN
COLORS OF SUNLIGHT AND
REFLECTS OTHER COLORS OF
SUNLIGHT.
SUNLIGHT HAS A FULL SPECTRUM
OF COLORS.
THINK OF THE RAINBOW.
AND WHEN THAT RAINBOW FROM THE
SUN HITS THE OCEAN WATER, THE
WATER ITSELF ABSORBS THE REDS
AND VIOLETS AND REFLECTS BACK
MOSTLY THE BLUE.
AND SO IT'S THE REFLECTED
LIGHT, THE REFLECTED COLOR, IS
WHAT YOU UNDERSTAND IS THE
COLOR OF ANY OBJECT YOU'RE
LOOKING AT.
SO, IT'S BLUE BECAUSE IT'S
ABSORBING THE RED COLOR OF
SUNLIGHT AND REFLECTING BACK
TO BLUE.
LUKE: HI.
MY NAME IS LUKE, AND I GO TO
RIVERSIDE ELEMENTARY.
MY QUESTION IS, I HEARD THAT
THERE'S A FLOATING ISLAND OF
TRASH.
WHERE IS IT LOCATED, AND HOW
BIG IS IT?
WILKINS: SADLY, THERE ARE
ACTUALLY SEVERAL TRASH ZONES
OUT IN THE MIDDLE OF THE
OCEAN.
EVERYTHING THAT WE TOSS INTO
THE STREAMS AND RIVERS
EVENTUALLY ENDS UP INTO THE
OCEAN.
SO, PLASTICS, BOTTLES, CANS,
EVERYTHING GETS WASHED OUT
THERE.
AND WITH THE OCEAN CURRENTS IN
THE BIG OCEAN BASIN, SPECIFIC,
THE ATLANTIC AND THE NORTH AND
THE SOUTH OF EACH OF THOSE
BASINS, THERE ARE THESE LARGE
AREAS CALLED "GYRES."
IT'S WHERE EACH HEMISPHERE
OF WATER IS CIRCULATING AROUND
THE CENTER OF THE OCEAN BASIN,
ITSELF, IN THE NORTHERN
HEMISPHERE AND THE SOUTHERN
HEMISPHERE.
AND SO ALL OF THE MATERIAL,
ALL THE FLOTSAM AND JETSAM,
ALL THE PLASTIC PARTICLES ALL
EVENTUALLY END UP FLOATING IN
A SHALLOW AREA, A SHALLOW ZONE
OF ABOUT 4 TO 5 TO 10 FEET
DEEP, AND MIGRATE OVER TIME
INTO THE CENTER OF THE OCEAN
BASINS WHERE IT ACCUMULATES.
THE FISH DON'T KNOW THE
DIFFERENCE, BECAUSE THE
PARTICLES ARE SO SMALL THEY
LOOK LIKE THINGS THEY MIGHT
EAT NORMALLY, AND SO THEY EAT
THEM, AND THEN THE FISH DIE,
BECAUSE THEY CAN'T DIGEST THE
PLASTIC EITHER.
IT'S A REAL PROBLEM, AND IT'S
VERY, VERY SAD.
MERCADEEZ: HI.
MY NAME IS MERCADEEZ, AND I GO
TO KAMIAH ELEMENTARY SCHOOL IN
KAMIAH, IDAHO, AND MY QUESTION
IS, WHICH OCEAN IS THE BIGGEST
OF THEM ALL?
SNYDER: THE BIGGEST OCEAN OF
ALL IS THE PACIFIC AT ABOUT 64
MILLION SQUARE MILES.
THE ATLANTIC IS ABOUT HALF
THAT SIZE AT 33 MILLION SQUARE
MILES, AND THEN THE INDIAN
OCEAN IS AROUND 24, 25 MILLION
SQUARE MILES, BUT THE PACIFIC
IS DEFINITELY THE BIGGEST OF
THEM ALL.
BAILEE: HI.
MY NAME IS BAILEE, AND I GO TO
RIVERSIDE ELEMENTARY SCHOOL,
AND MY QUESTION IS, HOW LONG
DO WHALES LIVE?
WILKINS: WHALES, BECAUSE
THEY'RE SO LARGE, AND BECAUSE
THEY LIVE IN SUCH COLD
CONDITIONS, HAVE A VERY SLOW
METABOLISM.
THEY AGE FAIRLY SLOWLY.
THEY CAN LIVE DECADES.
60, 70, 80 YEARS IS NOT
UNCOMMON FOR WHALES, AND WE
DON'T DO THIS BECAUSE WE SEE
WHALES BLOWING OUT BIRTHDAY
CAKES WITH CANDLES ON THEM,
BUT WHEN WE FIND WHALEBONES ON
THE SHORELINE, WE CAN LOOK AT
THEIR TEETH STRUCTURES AND
THEIR JAW STRUCTURES AND GET
AN IDEA ABOUT HOW OLD THEY
ARE.
MEGAN: HI.
MY NAME IS MEGAN.
I GO TO SAGLE ELEMENTARY
SCHOOL, AND MY QUESTION IS,
WHY DOES THE OCEAN HAVE
CURRENTS?
SNYDER: THE OCEAN HAS CURRENTS
FUNDAMENTALLY BECAUSE OF TWO
FACTORS; WIND AND THE FACT
THAT THE EARTH ROTATES.
MAJOR WIND CIRCULATION ON THE
EARTH IS THAT WINDS TEND TO
BLOW TO THE WEST AT THE
EQUATOR AND TO THE EAST AT THE
POLES, BOTH THE NORTH POLE AND
THE SOUTH POLE.
SO, IF YOU JUST IMAGINE --
RIGHT NOW IMAGINE THE PACIFIC.
SO, THE WIND'S BLOWING TO THE
WEST ACROSS THE EQUATOR.
THE WATER IS MOVING FROM THE
AMERICAS TOWARDS THE --
TOWARDS JAPAN AND THE
PHILIPPINES AND THE PACIFIC
SIDE, AND THEN AS IT HITS THE
WEST SIDE OF THE OCEAN, IT
THEN MAKES A TURN TO THE
NORTH.
FLOWS ALL THE WAY UP NORTH
WHERE IT CATCHES.
THEN THE WINDS ARE BLOWING TO
THE EAST, AND THAT ALSO HELPS
PROMOTE THE CURRENTS THEN TO
MOVE BACK TO THE EAST.
THEN THEY MOVE DOWN ALONG IN
THE NORTHERN HEMISPHERE DOWN
ALONG, SAY, OUR COAST, AND
THEN THEY GO BACK ACROSS THE
PACIFIC AGAIN AT THE EQUATOR.
NOW, WHAT CAUSES THOSE TO TURN
IS THE FACT THAT WHEN THE
EARTH TURNS, THE WESTERN
MOVING WATER IS FORCED TO TURN
TO THE RIGHT.
AND SO THAT COMBINATION OF THE
EARTH TURNING AND THE WINDS IS
WHAT CREATES THESE BIG OCEAN
-- WHAT ARE CALLED "OCEAN
GYRES" THAT HAVE CONSTANT AND
CONSISTENT DIRECTIONS OF
MOVEMENT.
[MUSIC]
CARTAN-HANSEN: EMILY
ASKS, IS IT EASIER TO FLOAT IN
AN OCEAN OR A LAKE, AND WHY?
SNYDER: IT ALL DEPENDS ON
WHAT'S HAPPENING IN THE LAKE
OR THE OCEAN.
BASICALLY, YOU FLOAT IN THE
OCEAN BECAUSE THERE'S SALT IN
IT, AND WHEN YOU PUT SALT IN
THE WATER, IT MAKES IT
THICKER, HEAVIER, DENSER, AND
IF IT'S THICKER, YOU CAN FLOAT
EASIER IN IT.
SO, IN GENERAL, IN AN OCEAN,
YOU CAN FLOAT EASIER, BECAUSE
IT CONTAINS A LOT OF SALT THAN
IF YOU TRIED TO FLOAT IN A
FRESHWATER LAKE.
HOWEVER, SOME LAKES, SUCH AS
THE GREAT SALT LAKE, ARE
EXTREMELY SALTY, SALTIER THAN
THE OCEAN, AND IT'S EVEN
EASIER TO FLOAT THERE.
SO, IT'S NOT JUST THE
DIFFERENCE BETWEEN THE OCEAN
AND A LAKE.
IT'S THE DIFFERENCE BETWEEN
SALTY WATER AND FRESHWATER.
SO, THE MORE SALT, THE EASIER
IT IS TO FLOAT BECAUSE IT
MAKES THE WATER THICKER, AND
IT CAN SUPPORT YOU.
YAROSLAVA: HI.
MY NAME IS SLAVA, AND I GO TO
RIVERSIDE ELEMENTARY SCHOOL,
AND MY QUESTION IS, I LIKE
SHARKS, AND I READ THEY LIVED
BEFORE DINOSAURS.
DO THEY HAVE THE SAME LOOK AS
THEY HAD A HUNDRED MILLION
YEARS AGO?
WILKINS: PRETTY MUCH.
SHARKS HAVEN'T CHANGED MUCH IN
THEIR APPEARANCE SINCE THEY
FIRST FORMED -- FIRST APPEARED
IN THE FOSSIL RECORD OVER 400
MILLION YEARS AGO.
THE ONE BIG DIFFERENCE IS THAT
THEY WERE MUCH LARGER BACK
THEN.
YOU HAVE SHARK SPECIES THAT
WERE 50 FEET LONG, WHICH WOULD
BE MUCH -- IT'S VERY HARD TO
VISUALIZE AND PROBABLY PRETTY
TERRIFYING TO EVERYTHING ELSE
THAT WAS IN THE WATER AT THE
TIME.
ONE OF THE MOST INTERESTING
FOSSILS IS THE HELICOPRION
WHICH IS A BUZZSAW-JAWED
SHARK.
THE TEETH ACTUALLY CAME OUT OF
ITS JAWS LIKE A BUZZ SAW.
IF YOU PICTURE A SAW THAT'S
GOING AROUND AND AROUND ON A
TABLE, THAT'S WHAT THE TEETH
IN THIS LOOKED LIKE.
THE SCIENTISTS AT IDAHO STATE
UNIVERSITY ARE THE BEST IN
STUDYING THIS, AND SOME OF THE
BEST FOSSILS HAVE COME FROM
EASTERN IDAHO.
ASHLEY: HI.
MY NAME IS ASHLEY, AND I GO TO
RIVERSIDE ELEMENTARY, AND MY
QUESTION IS, HOW DO WE KEEP
THE OCEAN WATER CLEAN,
HEALTHY, AND SUSTAINABLE?
WILKINS: I WISH I KNEW.
I WISH WE KNEW.
I THINK WE BEGIN BY TREATING
THE OCEAN WITH RESPECT.
MAYBE RECOGNIZING THAT THE
HEALTHY OCEAN MEANS A HEALTHY
PLANET FOR THE REST OF US.
EVERYTHING THAT HAPPENS IN THE
OCEAN EVENTUALLY COMES BACK ON
LAND; WEATHER, CLIMATE, WATER,
ALONG THE SHORELINE, A LOT OF
OUR FOOD.
ALL THAT MEANS THAT WE NEED TO
HAVE A HEALTHY OCEAN TO HAVE A
HEALTHY PLANET.
WHAT WE REALLY NEED IS WE NEED
TO HAVE MORE GOOD CURIOUS
INTERESTED SCIENTISTS WHO WANT
TO STUDY THIS PROBLEM LOOKING
AT HOW DO WE -- HOW DO WE --
SAY, HOW DO WE PROTECT AND
SUSTAIN THE OCEAN, AND WE ALSO
NEED TO HAVE WELL-EDUCATED AND
LISTENING LEADERS WHO CAN
LISTEN TO THE SCIENTISTS AND
ACTUALLY MAKE THE DIFFICULT
DECISIONS THAT ARE NEEDED TO
MAKE THE OCEAN SUSTAINABLE.
[MUSIC] CARTAN-HANSEN: I'M
SORRY, WE'VE RUN OUT OF TIME.
MY THANKS TO DAVID AND WALTER
FOR ANSWERING STUDENTS'
QUESTIONS.
WILKINS: THANKS FOR INVITING
US.
IT'S BEEN A LOT OF FUN, AND I
LOOK FORWARD TO SEEING ALL
THESE STUDENTS IN OUR
CLASSROOMS IN A FEW YEARS.
SNYDER: IT'S BEEN A PLEASURE.
I'VE ENJOYED YOUR QUESTIONS,
AND KEEP ON ASKING QUESTIONS.
CARTAN-HANSEN: AND MY THANKS
ALSO TO THE FOLKS HERE AT THE
MK NATURE CENTER FOR HOSTING
US.
NOW, IF YOU WANT TO LEARN
MORE, CHECK OUT THE OCEANS
AREA ON THE SCIENCE TREK
WEBSITE.
YOU'LL FIND FACTS, LINKS,
GAMES, OUR OCEANS BROADCAST
SHOW AND LOTS MORE.
AND EVERY WEEK, CHECK OUT MY
BLOG FOR THE LATEST SCIENCE
NEWS FOR KIDS ALL AT
IDAHOPTV.ORG.
THANKS FOR JOINING US.
WE'LL SEE YOU NEXT TIME ON
SCIENCE TREK, THE WEB SHOW.
[MUSIC]