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When I was a little girl, my mom would hold each of my hands and
lift me up as the waves crashed over her feet.
And as I grew up on the Jersey shore and was big enough to stand on my own,
there was no water too cold, or waves too rough to keep me from swimming.
And to this day, the sound of waves crashing brings a calm to my being.
It sounds like home.
Because like billions of people around the world, I grew up near a coast.
Sadly, we are changing our coasts in dangerous ways.
Our coasts are dynamic spaces.
They divide the world in which we live from the massive expanse of the ocean.
Here, in California, our coasts are rocky and cliffed.
Think Half Moon Bay and along Route 1.
But for many miles of the world's coastlines,
our water blends into land in a special ecosystem known as wetlands.
So what are wetlands?
Here water covers soil for most of the year.
And depending on where you're from, they go by many names.
They are mangroves and marshes, they are swamps and slews.
Today, I'll try to stick to wetlands for short.
And I want to show you that these wetlands hold far more economic and
environmental power than you think.
Wetlands protect us from the ocean by buffering against storms,
and they protect the ocean from us by filtering out our pollution.
And so now you're thinking, wetlands sound great.
What's the problem?
Over the past century, our wetlands have disappeared at an alarming rate.
Nearly half of the world's wetlands are already gone.
In the US, that's 220 million acres.
Here in the Bay Area, we filled in and
developed on top of 85% of our historic wetlands.
In other places we dredge our wetlands, physically removing them to
create more water for fishing and shipping or we dammed upstream and
we starved our wetlands of the dirt and salt they need to survive.
So, how do we fix this?
I'm here to convince you that, whenever possible, we must not develop or
replace our wetlands and
we need to get creative about restoring the wetlands we've already lost.
And to show you, let me share a couple stories of the power of a salt marsh.
It was the summer of 2012, and I was living on the Chesapeake Bay,
on the eastern shore of Virginia.
One morning I was awoken by a very particular, rotting smell.
Imagine the worst smell you can fathom,
imagine that that smell permeates your home, the air.
So I walk to the beach.
Just a couple hundred yards from my home.
And as I approach the water, that smell only got stronger.
When I finally reached the bay, there was no sand in sight,
only dead fish, as far as I can see, in any direction.
It was a fish kill.
This horrible event became a shockingly regular part of life
when I lived on the Chesapeake Bay.
So let's start with the science.
Farmers apply fertilizer to their fields to increase production.
While most of this fertilizer is used by those plants,
some of it washes into nearby streams and eventually into bays and the ocean.
Just like crops, phytoplankton,
the microscopic plants living in the water, thrive on this new nutrients.
These phytoplankton grow so fast that they trigger a change
that leads to the loss of oxygen in widespread areas of water.
Just like us, fish breath oxygen.
When fish reach these hypoxic zones, areas without oxygen,
they die in large numbers and wash up on shore.
This is a crisis in coastal communities.
It's not just an ecological blow.
This is an economic disaster for
all of the fishers who rely on these fish for their income.
But what if this fertilized water never reached the ocean?
What if, instead, this fertilized water went into wetlands, and
the plants there used all of the nutrients and left none for the phytoplankton?
For many years,
our coastal wetlands acted as this natural filter between land and water.
They absorbed the nutrients and
played this critical role in our coastal communities.
Sadly, with the loss of our wetlands, these hypoxic zones,
cover large regions of our world's more fertile fishing grounds.
Including much of the Gulf of Mexico today.
Yet, this is a story of hope.
In the Chesapeake Bay, we have seen fish kills decreased from 50 kills
each year from hypoxia in the 80s, to just ten today, with a management plan.
Our coasts are resilient when given a chance.
So let's re-imagine communities where fishers do not suffer at
the hands of farmers.
And now you know the power of a wetland to protect our ocean.
Let's talk about the power of a wetland to protect you.
Climate change has transformed what it means to live on our coast.
Flooding is already the most common natural disaster in the US.
And it's only becoming more common as sea levels rise and
storms increase in frequency and intensity.
Those of us who live and work on the coast are at the most risk.
In the 20th century, the Gulf Coast of the US was dredged for
expanded ports and new shipping lanes, with
the belief that wetlands held little value except breeding ground for mosquitos.
We lost an average of 34 square miles each year.
That's 16,000 football fields.
It's bigger than Palo Alto, every year.
Tragically, we were reminded of the true value of our wetlands when
Hurricane Katrina hit the city of New Orleans in 2005.
While Katrina was dangerous, with or without wetlands,
the absence of the natural defense led to higher water levels and
more flooding and likely more property damage and lives lost.
In an attempt to mitigate this risk, we have hardened our coast.
A process of replacing the natural defenses of marshes and
sea grasses with seawalls and the levies to separate land and sea.
Concrete walls looks strong, but
with one major storm event like Katrina, these walls are breached and
destroyed, taking with them the land they were meant to protect.
Nothing can guarantee safety or permanence in the face of Mother Nature.
Yet natural defenses can provide a sustainable solution to questions of
coastal storm protection.
Wetlands may not seem as strong as concrete, but
researchers found that the presence of mangroves in Florida reduced waves
caused by wind by 75% during a storm surge.
For every mile width of man growth there was a decrease of nearly two and
a half feet of water level rise.
For people of the Gulf Coast and for people of coasts around the world,
wetlands really can mean the difference between life and death.
So now what?
Today, nearly half of the world's population
lives within 100 miles of a coast.
Eight of the world's ten largest cities sit directly on the sea.
We must protect our coastal wetlands to protect our coastal communities.
Thankfully, humans are brilliant adoptable creatures.
And guess what?
Wetlands are resilient too.
And look, I'm not saying we never develop wetlands.
I'm saying when we need to make this difficult decision,
we consider the true value of all wetlands provide us.
And get creative about replacing all of the natural defenses we'd lose.
Because if we decide to protect our coastal communities by restoring and
maintaining wetlands, our intervention will turn the tide.
So imagine a future where we protect our coasts in
the face of storms and we protect our ocean against negligence on land.
Imagine a future where I have a coast to enjoy the waves with my daughter.
Because if we protect our coastal wetlands, they protect us.
And our coasts tell a story of hope if only we choose to listen.
Thank you.
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