Download File - Richard Goodman

BE A
SCIENCE DETECTIVE!!!
You are at the beach with
your friends over the hot
summer and the water is a
warm 80 degrees
Fahrenheit. NICE.
You are at the beach with
your friends over the hot
summer and the water is a
warm 80 degrees
Fahrenheit. NICE.
The air gets down to the 60s
at night.
The very next day the water
drops to 60 degrees!!!
Brrrrrr.
Does the ocean cool down that
quickly in overnight?
Does the ocean cool down that
quickly in overnight?
NO!
Water does not heat up or cool
down fast.
Water does not heat up or cool
down fast.
Water does not heat up or cool
down fast.
Our oceans moderate Earth’s
temperatures .
WHY?
WATER has a physical property
known as high specific heat.
Can you give me other examples of high or low
specific heats?
SO, HOW CAN WATER TEMPS
DROP SO FAST AT THE SHORE?
DANNNG!
So, there MUST BE SOME
OTHER EXPLANATION!
Water couldn’t change its
temperature THAT fast.
What does a scientist DO???
(hint: I just did it right now!)
ASK QUESTIONS!!!!
You are a
SCIENCE DETECTIVE!!!
START WITH THE BASIC
QUESTION…..
How could the water
temperature drop so fast?
Is it the same water that was
there yesterday?
COLD WATER MUST HAVE
COME FROM SOMEWHERE
ELSE!!!!
But, where can you find such
cold water so close to warm
water???
???????
Have you ever dived really deep
into a lake or ocean? What does it
feel like?
Ah HA!!!
So, this cold water could have
come from BELOW!!!!
NOW, LET’S MAKE A
SCIENTIFIC PREDICTION
(hypothesis):
The temperature of the
beach water may drop fast if
cold water comes up from
the deep.
But WAIT A MINUTE!
Remember our lessons on
density.
What is less dense…warm stuff
or cold stuff?
Remember our lessons on
density.
What is less dense…warm stuff
or cold stuff?
Remember our lessons on
density.
What is less dense…warm stuff
or cold stuff?
Hot stuff is usually LESS dense &
cold stuff is usually MORE dense
So how could COLD water RISE
over WARM water?
???????
Cold water must have been PUSHED UP to
the surface…against the density!
NOW, WE CAN MAKE A BETTER
SCIENTIFIC PREDICTION
(hypothesis):
The temperature of the beach
water dropped so fast…
because COLD water from the
ocean bottom pushed up to the
surface.
NOW, WE’RE GETTING
SOMEWHERE!!!!!
WE CAN EXPLAIN HOW THIS
COLD WATER PUSHED UP TO
THE SURFACE!
WE ARE SCIENCE
DETECTIVES.
What makes surface currents
move around the planet?
???????
SURFACE CURRENTS are
moved mostly by WIND!
These surface currents can move
global precipitation patterns…
These surface currents can move
global precipitation patterns…
What is WIND?
Some ideas???
WIND IS SIMPLY
AIR MOLECULES
MOVING FROM
HIGH PRESSURE TO
low pressure.
What air has HIGHER
PRESSURE….
WARM AIR or COLD AIR?
(remember what happens to a balloon
in hot water?)
WARMER AIR has
HIGHER PRESSURE!
Where around Earth do we find
WARMER air?
WARM HIGH PRESSURE AIR from
the EQUATOR blows TOWARDS
COLD, low pressure air at the
North and South Pole.
Winds blow ocean water from the
warm EQUATOR towards the cold
N & S POLES.
So, what happens when water
gets to the BITTER COLD
NORTH or SOUTH POLE?
d’uh…freezes.
Yep, it freezes! Turns to ICE.
Forms a GLACIER!
Is ice fresh or salty?
Ice is fresh.
When ocean water turns to ICE
at the North & South Poles,
FRESHWATER FREEZES!
(not salt water)
Hmmmm….interesting
Which one is MORE DENSE,
SALT or FRESH water?
So, which one will sink below
the other?
DENSER SALT WATER PLUNGES
DOWN BELOW WHEN FRESH
WATER FREEZES AT THE POLES.
Millions of gallons of salt water
DROP to the bottom of the
ocean whenever freshwater
glaciers form!
WHAT DOES ALL THIS
PLUNGING OCEAN WATER DO?
Only one direction it can go!
Sinking unfrozen saltwater at the
poles create DEEP water currents
that rush back to the equator!!!
So now, SCIENCE DETECTIVE,
you’re at the BEACH.
In ONE DAY the ocean has
cooled 20 degrees.
You hypothesize that cold
water must have been pushed
up from the bottom of the
ocean.
HOW does cold water get
pushed up to the surface at
the beach?
When deep-sea, salt water currents rush down
from the poles, these DEEP currents push up
cold water (& live/dead NUTRIENTS) up
the continental slope to the shoreline!
We call this UPWELLING!
Surface winds have
something to do with
UPWELLING….
As the cold water is pushed up,
gentle surface winds blow the
warmer shallow water away.
We call this UPWELLING!
COLD WATER & NUTRIENTS rise UP the slope
towards the shore.
CAUSING A
FEEDING
FRENZY!
We call this UPWELLING!
COLD WATER & NUTRIENTS rise UP the slope
towards the shore…BEST FISHING EVER!!!!
show infrared earth upwelling photo
Infrared upwelling on earth!
CONGRATULATIONS!!!!
YOU science detective YOU!
Watch the relationship
between sooty terns & Alvin
shrimp!
http://video.pbs.org/video/233103
4874/
watch 1st 23 minutes, skip 23:10-24:10, end around 28 minutes in