Transcript Beach Erosion

Introduction to Erosion
Beaches erode.
Ironically, erosion is the very thing which
created the beaches.
When oceans first covered the surface of
the Earth, there were no beaches. Only
rocky shores.
Over the course of time, these rocks were
broken down into stones.
Erosion
These rocks were in turn broken down
into pebbles
Then into gravel
And finally into sand.
Rivers also carried sand formed in the
same way into the oceans.
This is how our beaches were formed.
Why is Beach Erosion a
Problem?
Over 75% of the US population lives
within 100 miles of the beach.
Most communities were built based upon
what was then the current location of the
beach.
Beaches in some NJ communities were
extremely wide.
Some beaches are getting narrower and
narrower.
Why is Beach Erosion a
Problem?
Entire homes have been washed away.
New Jersey earns millions of dollars each
year from tourists who come to visit our
beaches.
We spend millions of taxpayer dollars
each year to combat beach erosion.
Sometimes NJ tax dollars are used to
protect and replenish private beaches. Is
this right?
Causes of Beach Erosion
Waves
Storms (storm surge)
Currents
Tides
Wind
Humans
We have built structures which disrupt the
fragile balance of nature.
Waves and Beach Erosion
Tough Questions?
Once houses, or
entire towns, have
sprung up, we are
faced with the
following choice:
Succumb to nature
and let the sea
swallow expensive
buildings? or…
Fight back and seek
to control nature?
Ocean City, NJ
Another Tough Question?
On average, New
Orleans is now 6 feet
below sea level.
Groins
Rocky structures used
to slow down beach
erosion.
Jetties
Rocky structures
designed to protect
inlets from the
erosion caused by
ocean waves.
“Ironically, geologists now know that
such seawalls hasten the loss of the
beach, actually increasing the waves’
ability to scour away sand.”
“Once thought to stabilize beaches,
groins turn out merely to block the
natural movement of sand, ultimately
leading to more erosion than they
prevent.”
-Oceanfront Battlefront,
Audubon Magazine 1998 p.53
Discussion Question
What impact will global
warming have on beach
erosion?