PubTalk 4/2018 - Coral Reefs
Title: The Role of U.S. Coral Reefs in Coastal Protection - Rigorously valuing flood reduction benefits to inform coastal zone management decisions
- Coral reefs are a first line of coastal defense
- We can account for the physical defense that reefs provide
- We can provide value-based information to guide restoration efforts at management-relevant scales (10s of meters)
- We can direct ecosystems restoration efforts to reduce risk and increase the resiliency of coastal communities
Image Dimensions: 480 x 360
Location Taken: Menlo Park, CA, US
- [multiple responses]
- And welcome to the latest
installment in the U.S. Geological
Survey public lecture series.
I’m Helen Gibbons from the
Pacific Coastal and Marine
Science Center in Santa Cruz.
And I have the pleasure of working
with tonight’s speaker, Curt Storlazzi.
Before I introduce Curt,
I would like to urge you all
to come back for next
month’s lecture on May 31st.
The title of that is
Yes, Humans Really Are
Causing Earthquakes –
How Energy Industry Practices
Are Causing Earthquakes
in America’s Heartland.
As a reminder, you can
pick up a flier on the back table.
And now to tonight’s lecture about
the role of U.S. coral reefs in
coastal protection, presented by
research geologist Curt Storlazzi.
Curt is currently the chief scientist
of the USGS Coral Reef Project.
He leads a research team of scientists
who examine the geologic and
that affect the sustainability
of U.S. coral reefs and reef line coasts.
Curt has authored more than
130 scientific papers, reports,
and book chapters on these topics.
Curt received his bachelor
of science degree from the
University of Delaware in 1996
and his Ph.D. from the
University of California
at Santa Cruz in 2000.
He has been a research
geologist with the USGS
Coastal and Marine Geology
Program since 2003,
working across the Pacific,
Atlantic, Arctic, and Indian Oceans.
Curt is on the steering committee
for the U.S. Coral Reef Task Force,
and he regularly contributes
scientific reviews for the
U.S. Global Change Research Program,
the National Park Service,
the U.S. Fish and Wildlife Service’s
Landscape Change Cooperatives,
the USGS Climate Science Centers,
and NOAA’s National Marine
The USGS is pleased to
bring you Curt’s presentation on the
role of coral reefs in protecting coasts.
Please join me in
welcoming Curt Storlazzi.
- Thanks, Helen.
Well, seeing we’re going to be talking
about a lot of places across the U.S.,
I first would like to say hafa adai,
talofa, aloha, hola, and good evening.
Thank you for joining us.
So today’s presentation –
or, this evening’s presentation
is going to be about the role of
coral reefs in coastal protection.
One of the things we’ve done
at the USGS in the hazards mission area
that the Coastal and Marine
Geology Program I work under,
is we’re really good at describing
kind of hazards and catastrophic events
and a lot of times changes to
coastal environments –
erosion and storm impacts
and degradation of environments
such as marshes
and coral reefs.
About a decade – a little more than a
decade ago, our director of the USGS
kind of challenged many of us to – okay,
let’s talk about some solutions here.
And it really reframed the
way a lot of us approach things.
And at least for coral reefs,
this is hopefully a way that we can
better think about coral reefs and protect
and preserve them as we’re required to
under U.S. Executive Order 13089,
the U.S. Coral Reef Protection Act.
So I’m Curt Storlazzi with the
Coastal and Marine Geology Program.
This work is done in conjunction with
Mike Beck at The Nature Conservancy,
Borja, Erik, and James Shope at the
University of California at Santa Cruz.
As with most things we do,
it takes a team to do these things,
and it’s a real honor to
work with these folks.
So where are U.S. coral reefs?
Well, the U.S. has about –
over 22,000 square
kilometers of coral reefs.
And as you can see from the pie chart,
about 70% of them are in the Pacific.
In total, the U.S. – U.S. coral reefs
have been estimated by a NOAA
technical report in 2013 to generate
just a hair over $2 billion annually.
Now, that’s primarily due to tourism,
fisheries, and ecosystem integrity.
So why should we
care about coral reefs?
Well, most importantly,
they’re really the rainforests of the sea.
If anything, they exceed that.
They have a higher species diversity
than the rainforests, although they
only cover less than half a percent of the
ocean’s seafloor – which remember,
the oceans are 70% of the Earth.
They’re home to, however,
more than 25% of all marine species.
They’re a primary source of
protein for most island nations.
They’re also –
importantly, they’re the
nursery habitat for many larger
oceanic commercial species.
And obviously, for any of you that
go to these places, obviously tourism
is a major source of income for
a lot of these small island nations.
So recently, we’ve done some work
on corals and coastal protection.
Here’s a plot.
Across the X axis here is incident
or incoming wave energy plot
versus wave energy dissipated.
And what this shows
is that reefs reduce
about 97% of the
incoming wave energy.
So they actually act like kind of natural
breakwaters, protecting coastlines.
the U.S. Department of Defense –
we have wrapped up a project –
actually, we wrapped up the
project yesterday [chuckles]
for the U.S. Department of Defense
looking at the roles of coral reefs on
wave-driven flooding of coastlines.
And so here on the X axis, we’re talking
about reef hydrodynamic roughness.
So no roughness
is a smooth reef.
roughness has a lot of live coral.
So think about – like, they stick up
and it’s – like, causes a lot of friction.
And what we see is, if we start over
here on the right side with high, good,
healthy coral reefs, they dissipate a lot of
wave energy and cause lower flooding.
But if those coral
reefs get degraded,
it results in much higher
So corals protect coastlines,
however, if they get degraded,
they become less effective.
You get more coastal flooding.
However, I think most of you
have seen in the newspapers
that coral reefs are at risk.
And more than 10% of the world’s
reefs has already been lost,
and another 60% are threatened
by anthropogenic activities –
mostly land-based sources of pollution.
Now, I hate to tell you,
but more like 90% are by global impacts,
such as temperature-induced
bleaching and ocean acidification.
And this has been
in the news, scientific
articles, and elsewhere.
Now, I’m going to make a statement
here that in the U.S., I’d say we
struggle to protect and preserve our
coral reefs along populated coasts.
And when I say “populated coasts,”
I mean, like, there’s the
northwestern Hawaiian islands –
over 1,000 kilometers of coral reefs.
We really can make those places
protected because no one’s there.
However, they don’t provide
those services to the people
who live on the islands.
And so, in the U.S., we average –
along populated coastlines, less than
1% of the coral reefs are protected.
Now, to put that in context,
Haiti has 20%.
And I’d argue that that’s mostly due
to economic and geographic reasons.
And what I mean by that is, first,
the geographic – like, yeah, let’s go
make that marine protected area –
protect those coral reefs away from here
that are, you know,
not in my backyard kind of thing.
But also for economic
and geographic reasons.
So say I’ve got a coral reef right here,
but I want to build – and I’m not
knocking anyone in the construction
industry or anything – but say I want to
build whatever structure that
may impact those coral reefs.
Well, I’d argue that, well,
you know the fisheries?
Well, most of the fish are –
live over on that reef.
And, well, the high diversity
is over on that reef.
And all the tourist boats
go on that one over there.
So we – if we damage my
reef right here, no problem.
We’re going to be okay.
And, in return, you know, we’re going
to employ 200 people to build this
for two years and then 50 people
to maintain it for the next 30 years.
Yeah, just totally making numbers
up here, but – and so that’s why –
and then we – then we argue, well,
but there’s ecosystem integrity and –
well, but you said the
tourists don’t go here.
And so, you know, it’s –
it usually gets balanced out.
You know, you’re going
to do a cost-benefit.
Well, there’s a lot of benefit and,
well, what’s the cost?
So it seems like it’s lost for that way.
So if their innate beauty, tourism,
fisheries, and species diversity are
not a compelling enough argument
for protection and restoration
of coral reefs, what is?
Well, again, going back to the
one thing we in the hazards mission area
look at a lot is natural catastrophes.
Now, this is a plot of natural catastrophe
overall losses in green,
insured losses in blue.
These are adjusted dollars.
So it’s not just that, oh, well,
you know, the dollar has gone up.
But these are adjusted losses.
And so you see it
starting to rapidly grow,
both the number and the
cost of these catastrophes.
Why is this? More people.
We build more stuff. It gets damaged.
Not anything new here. But it is
growing, and it’s growing faster.
So when we think about coral reef areas,
well, here shows nice – these coral reefs
causing these waves to break offshore
here off Honolulu and Waikiki,
protecting a couple billion dollars’
worth of infrastructure.
Here in Miami, Florida, there’s some
expensive property right there too.
Hagatna, Guam –
that’s the capital of Guam.
Pago Pago is the
capital of American Samoa.
And so, in all these places,
the protection of the shoreline
is dynamically tied to the health and
quality of those offshore coral reefs.
Now, not only is it a concern for,
you know, those of us here, but the
Department of Defense also has some
pretty expensive gear out there too.
And, you know, the Department of
Defense has over $100 billion worth of
infrastructure in low-lying places like this
that, again, are protected by coral reefs.
So going back to that question, you
know, what’s a compelling argument?
And I’d say
dollars and lives.
One of our [chuckles] – one of our
people on our executive leadership team
said to me a couple years ago –
he’s, like, the only thing
that matters in Congress
is dollars and lives.
And so, okay, well,
let’s try to see if we can
quantify the coral reefs
in terms of dollars and lives.
So my colleague Mike Beck
and [inaudible] Lange did a project
for the World Bank Group basically
trying to value coastal protection
services for mangroves and reefs.
And they did this at a global scale.
Every 10 kilometers around
the world – incredible project.
And so what they did is,
they measured – they estimated
or modeled waves offshore,
how they got closer to shore,
and how they came over habitats,
either over reefs and mangroves.
And then they estimated the flooding.
So here would be a hypothetical
flooding line with the habitat.
And then, if you remove that habitat,
that flooding line is
going to be further inland.
And then what you do
is you quantify the damages
between these two,
and that’s the value of that habitat.
Now, to do this at a global scale,
and to do this with, you know,
data from disparate countries,
you kind of have to go to
That’s what you’re stuck
with to do it consistently.
And so they used kind of some
1980s type of technology and models.
Because that’s all they could
do with this kind of scale.
But they did it, and they showed,
you know, coral reefs protect,
you know, over 200 million
people around the globe.
And hundreds of millions of dollars,
potentially, of damage.
So, well, when you get someone
like myself involved, you look –
sadly, you make things
a lot more complicated.
And so we basically developed –
here in the U.S., where we’ve got
a lot more information, a lot more data,
and because – like, we did this project
on coastal flooding for Department
of Defense, we have a lot more
complicated tools that give us
a lot more resolution and precision.
And so we could do it
at a much higher level.
But it’s a heck of
a lot more complicated.
And so I apologize, but I’m Italian,
and so I’m going to show you
how we make sausage.
So just to explain where we’re
doing this, we’re doing this
for all U.S. coral
reef line shorelines.
So that’s the Commonwealth of
the Northern Marianas in Guam.
Let’s see. Commonwealth
of the Northern Marianas
is the blue one
right over Helen’s head.
Guam’s the one on the other side
of the Hawaiian flag over there.
which is not flagged over there.
Hawaii’s the one that
looks like the British flag.
Then we have Florida, the U.S.
Virgin Islands, and Puerto Rico.
These all seem like pretty
small areas, right? Little islands.
Well, if you actually total it up,
it’s over 3,000 kilometers of shoreline.
Anyone know how long
the U.S. part of the West Coast is?
So it’s actually 50% longer –
more shoreline than the
U.S. West Coast. That’s a lot.
And if you actually totaled up
the exclusive economic area,
the – you know, if you take 200
nautical miles off there of mineral rights,
water rights, fishery rights,
it’s actually more than the
U.S. East Coast and
Gulf Coast combined.
Okay, so sausage. But this is
the cool thing to nerds like me.
So the first thing we wanted to do is we
wanted to get the wave climate off here.
And so my colleague Borja Reguero
did a wave hindcast using atmospheric
models to model waves all around
the globe every hour for 61 years.
That’s a lot. It was basically his
Ph.D. thesis, but he’s a smart kid.
And so he did that.
However, we can’t run 61 years
of hourly data, which is half –
basically half a million data points –
at all shore – all those reef line
shorelines around the world.
It’s just way too much.
So a wonderfully brilliant lady,
Paula Camus, at the
University of Cantabria in Spain,
developed this technique
where we can pick kind of –
if there’s a scatter of data, we pick
points in that that best represent it.
So we can take that half-million data
points and turn it into 500 conditions.
Which is a lot easier to run. [chuckles]
You know, orders of magnitude less.
So then what we do is we run those
500 conditions through this model called
SWAN, or Simulating WAves in the
Nearshore – really standard wave model.
So this is showing
wave heights –
so high wave heights in red,
low wave heights in blue.
This is the tip of the Florida Keys.
So you have big ocean waves.
As they start to propagate
across the reefs, they start to
decrease in wave energy,
and so you’ve got much lower
wave energy close to shore.
So that’s our step here.
And then what we do is
we bring it – we extract that data
at these transects every
100 meters along the shoreline.
So every 100 meters along
3,000 kilometers of shoreline.
That’s a lot. [laughs]
Just doing these SWAN models,
we ran 37 SWAN models,
and that was 98 days
of processor time.
Thank gosh for numerical
modeling clusters. [chuckles]
And thank gosh we didn’t do this in the
wintertime when the power goes off.
So then we set it up
on these cross-shore transects.
And so – oh, so real quick – at the end
of those cross-shore transects, what we –
we take Melissa’s mathematical
computations, we regenerate from
these 500 conditions that 500,000
hourly data points for 61 years.
And then we use that in a model
to determine return periods.
So most of the engineers, they want to
know, what’s the five-year wave height,
the 10-year wave height,
the 100-year wave height.
I don’t know why – many of you
in here are probably engineers
and can explain all that –
why you want that,
but that gives us those
kind of return interval storms.
And so then, what it allows us to do is
to pick – in our case, we were running
the 10-, 50-, 100-, and 500-year storms.
But we can pick it off – basically,
we model a distribution through
the data – some cool math stuff.
And so, again, that gets us
to our return interval storms.
And now it’s to model
the effects of the reef.
So the NOAA Center for Coastal
and Ocean Science undertook,
in the 2000s, an effort to map all U.S.
coral reefs at a scale of about an acre.
And so they mapped them –
you see ranges here –
zero to 10%, 10 to 50% coral cover,
50 to 90% coral cover, or 90 to 100%.
So this is Lahaina, Maui –
here’s the Lahaina Harbor.
So this was the original capital of Hawaii
when it was run primarily by whalers.
And so you see there’s
a distribution of reefs –
sometimes extend further offshore,
sometimes have higher coral coverage,
sometimes have lower coral coverage.
And sometimes there’s less of them.
And so you see, again,
here is our transect
spaced every 100 meters
along the shoreline.
So now we have coral coverage
along our cross-reef transects.
So now I’m showing you an example
of one of these cross-reef transects.
So this is from some distance offshore.
This is sea level.
So here’s the shoreline.
This line is actually –
downtown Lahaina sits right in here.
And so it goes offshore,
and here’s some reef in red.
There’s some more coral cover here
and here. Little bit here and here.
So the top line is
showing it with the reef.
And then what we do is, based –
my colleague Kim Yates and
our colleagues in the St. Petersburg
office in Florida have shown that,
because of pollution, because of
thermally induced bleaching,
that a lot of reefs
around the globe have decreased.
The corals have died,
and the reefs have degraded.
Now, they showed
Some places it’s 6 or 7 feet.
Some places it’s 3 feet.
Because we don’t have that data all
around – mapped all around the U.S.,
what we did is we assumed – we just
removed in the model a half-meter –
about a foot and a half
of the reef and took all those
live corals and
And so what you’re seeing here is –
the gray is kind of that reef minus the
coral versus the red’s with the coral.
So now we can run the model
over the profile with the
reef and without the reef.
And what that does is,
we used a model call XBeach
that the U.S. Army Corps of Engineers
and Deltares in the Netherlands
and the University of Miami
developed to look at storm –
flooding and erosion
along the U.S. sandy shorelines
of the eastern Gulf Coast.
Works great there.
However, if you think about
the sandy shores of the East Coast,
they’re relatively linear.
They’re relatively gently sloping.
Coral reefs are pretty
much anything but that.
And so the model didn’t
work for this environment.
However, working with my colleague
Ap van Dongeren and Ellen Quataert,
Deltares, during this big DoD project
we just finished up, it let us do enough
experiments to heavily modify the
model to be able to work for coral reefs.
And so what we’re showing here is,
this is now the flood level, right at
this shoreline here. So what you’re
seeing is, red is with the reef.
So the water levels are about a
half-meter above normal and kind of
hit the shoreline here with the reef.
Now, when we remove this reef,
now the flood levels are even
higher and extend further inland.
So we can model the
effects of the reef.
And so remember, these are done
every 100 meters along the shoreline.
So that was a hair over 30,000 models.
And that took us over 1,000 days of
processor time. Again, thank gosh
for numerical modeling clusters.
Okay, so now we
can make flood maps.
So here we’re showing –
this is Key West.
This is for a
So remember, we’re talking
different return interval storms.
So this is the – kind of the average
storm you’d see once every 10 years.
And so the blue dots
are the points where
intersect the shoreline.
This greeny-yellow-ish – sorry – limon –
I don’t know what you’d call that color.
But this is the flood extent.
And you see it floods inland.
And that’s with the reef. Now, red is
without the reef, which is further inland.
And so basically, everything in this
little red zone is the area protected
by the coral reefs. And hopefully
you can see the resolution of this.
We’ll zoom in on some places
elsewhere where – we’re doing this
at every 10 square meters.
So at the scale of your house.
Along 3,000 kilometers of shoreline.
So here shows a 1-in-10-year storm.
Here shows a 1-in-100-year storm.
So the flood lines are –
bigger storm, bigger waves,
And so, again, you can see the red – the
area between the yellowish whatever and
the red – the red areas are the areas – the
areas effectively protected by coral reefs.
One thing you should note here
is that the relative amount –
while there’s greater flooding here,
the relative amount is actually –
protected by the reefs is less.
I’ll show that here again.
So now that we have what we call –
these are flood masks, or this is a mask,
or a coverage, of the floodwaters.
Now what we can do is start to say,
well, what’s in those areas?
So the U.S. Census Bureau,
every 10 years,
conducts the U.S. census.
They put it in a
database called TIGER.
And so you have everything
about how many people are there,
how many people live
in a given household,
their – you know, whether it’s poverty,
different levels of income,
their age, sex, education. So you can
parse that out and say, okay, where’s –
how many elderly people are in a
location? How many young people are –
education, how many low-income,
minorities – all the information.
And so our colleague Nate Wood,
who’s in Western Geographic here,
has developed some really cool tools
that lets you basically dig into
these incredibly difficult,
confusing databases and assimilate that
so that we can match our flood
masks and that information.
So for example,
here is now south Maui.
Hopefully you can see here – because
I made them a little bit translucent –
now you’re looking at individual
buildings in those flood masks.
So pretty high resolution.
Kind of like Google Earth, right?
What’s the first thing everyone
does in Google Earth?
Goes and looks
for their house, right?
So now you can
go look for your house
and see if it’s protected
by coral reefs or not.
But so, in this area – the red area, again,
is the area protected by coral reefs.
And so what we can do is
match that up with census data and say,
how many people are in those areas?
Are they children? Are they elderly?
Are they low-income?
Are they high-income?
Are they minorities?
Are they this, that?
All that information is in there.
So we can quantify.
And that’s really good because
we understand the impact.
Is it disproportionately hitting a certain
age group, a certain income group?
And we can understand those.
Again, that’s more of an ecological
kind of thing – or, anthropologic.
But we can do those things.
we’re just counting bodies.
Now, the Department of
Homeland Security and FEMA
have a database called Hazus.
And what this does is it has
all the information about
what those buildings are.
You know, are they essential facilities?
Are they power plants?
Are they water treatment plants?
Are they roads?
Utilities like power?
High-potential loss facilities,
hospitals – building-specific data.
And some of the
is what they have – is what
we call depth-damage curves.
So this would be, like,
zero depth and some high depth
and zero damage
and high damage.
So basically, with no flooding,
nothing gets damaged.
But say – like, say this line here,
maybe this is a wooden house
where water gets up to a certain point,
and it tears the whole thing down.
Maybe this is like
a concrete structure
where the water gets higher and higher,
and it slowly damages it more.
So we have all this information,
so it’s not just assuming,
a building gets wet, it’s damaged.
It’s really, how much it has to get
wet for that to fail, and that’s based on
the different building properties.
So great data set, and we can use our
flood masks and the depths in those.
So, again, here’s our same area.
Our red’s showing our
area protected by corals.
And we can all the sudden
go in and say, okay, what’s the
value of those buildings?
So, you know, in these –
you know, red, we’re talking,
you know, millions of dollars
of homes and less are here.
We can also say how
many of those are commercial,
how many of those industrial,
how many of those are religious,
how much are those government,
agricultural – my gosh, there’s, like –
you’d be – it’d blow
your mind how much
information there is out there.
But in this case,
we’re just totaling the value.
And, again, why these numbers
may be small – some of these may be –
some of these may be partially damaged,
or not damaged at all, because in some
places, the flood depths are so low.
So, like, if you were to look at some of
these averages, you’re, like, oh,
well, it’s only 100,000 per building.
Gosh, this is a place with
really expensive property.
Well, that just means the property is
not completely destroyed, in some cases.
So the thing is, is we know,
well, you know, when your
business is demolished,
it’s kind of hard to work.
And when your house is demolished, it’s
often hard to stay there and go to work.
So one of the things we want to
say is kind of a follow-on step
from this is to look at the
impact for the – basically, the impact
of the GDP – people’s ability to work.
So it’s kind of that next follow-on step.
And so one of the calculations
we can make is the number of people
flooded times the average
GDP per person per year.
Now, this is a older number because
the census was only done in 2010.
Hazus was done in 2010.
So we’re using a 2010 GDP number.
I think the GDP now is 54,600. But we
have to be consistent in our data.
Then we did the number of
commercial and industrial buildings,
saying that each one
of those is a business.
And the average – if you
go to the Department of Labor,
15 employees per business.
So we just take –
multiply 48,400 times 15 employees.
That gives us just a hair under
3/4 million dollars per business per year.
So that we can then go back in here and
say, okay, well, this is 27 businesses,
and these are 180 people, and thus
compute an economic disruption.
So quantifying the benefits.
Basically, we have these kind of plots.
So along the bottom, it’s showing you
examples – different return periods.
So a 10-year storm, 100-year storm,
which is much bigger,
and then a 500-year storm,
which is, like, my gosh, horrible.
And what we’re showing you here is –
in this example, we’re just showing
a theoretical population.
And so right now, we have a current –
or, the existing conditions with our reefs.
And then the red is with reef loss.
So in all of these cases, the difference
between these two is about 500 people.
So it’s about, you know,
1,400 to 1,900 in this case.
So obviously, the – both of them go
up with bigger and bigger storms.
However, on this side,
we’re showing the percentage change.
And so that 500 people, for roughly –
or, 400 people for roughly –
out of 2,000, is actually about,
you know, a little over 30% change
between this line and this line. However,
these lines are much higher, right?
So now we’re at 500 –
or, 400 out of 3,500.
So that’s, you know,
only about 18%.
And so, even though there’s about
the same amount of people protected
because this line’s lower here,
it’s a larger proportion.
So what this actually shows is that
the effectiveness of reefs in hazard
risk reduction is greater in actually
more frequent, smaller storms.
Now, why that’s good is,
you don’t have to say, oh, gosh,
well, it’s only effective in that 500-year
storm, and gosh, we’ll never see that.
But this is saying the decadal storm,
you’re getting more effective.
And how long is the average
mortgage on a house?
You’re going to see a couple
of those kind of storms.
So it’s not just, oh, this is something
we don’t have to worry about.
Hey, they’re really effective
at useful time scales –
on the time scales that
we make financial decisions.
So now I’m going to
show you some actual –
some data and some of our calculations.
So both these plots are showing –
pardon me – [coughs] – the number
of buildings for a bunch of storms.
So, again, the 10-year, the 50-year,
the 100-year, and the 500-year storms.
The red is with reefs.
The blue is without reefs.
So it’s – basically,
when we remove the reefs,
more buildings are getting –
would get damaged.
I’m showing you three
sets of numbers here.
AED is the annual expected damage,
or the expected value of losses
per year with the reef, would be,
in this example, 169 buildings per –
or, 169 buildings per year. The annual –
the AED without reefs is 731.
And then, if we do the annual
expected benefit, or the expected
value of avoided losses per year,
it’s 500 – basically, 562 buildings
per year that coral reefs
protect on the island of Maui.
Here on Guam, where there’s
less development at the coastline –
it’s mostly up on the high
limestone plateau – lower numbers.
Same kind of trends.
Increases with increasing storms.
Without reefs is higher.
But our annual expected
benefit is now just 19 buildings.
We go to looking at
the resulting damages.
So remember, the damage is a
function of – not only is it flooded,
but how deep it’s flooded and
what the – what kind of building it is.
We see that the annual expected benefit
is about $63 million per year for Maui.
And Guam, with the fewer buildings,
is only $4.3 million per year.
But that’s per year.
So you think, over the lifespan of
an average building or a mortgage,
that’s – and then, if we do the
number of people, again,
we have the same numbers.
With reef, without reef,
and the annual expected benefit.
It’s about – in Maui, it’s 1,845 people
per year. It’s a pretty big, high number.
And then the – Guam, again
with fewer people by the coastline,
it’s only about – just a hair
over 63 people per year.
Okay, so let’s pull all that together.
So if we look at the damage in
millions and the number of people
for Guam, we have basically
$63 million a year in damage and 1,845.
Well, if we take that 1,845 people times
that annual contribution of GDP
per year, that’s 89 million per year.
We add that to the property damage,
that totals about $152 million
in total avoided damages
and economic disruption per year.
It’s a good number.
And to put that number in context,
the value of – for all the eight islands
in the state of Hawaii for recreation,
tourism, and fisheries for all of them
combined is 426 million a year.
So that 152 – just the damage
risk reduction – hazard risk reduction
is a third of that.
For one island.
And remember, Oahu has got
90% of the people and
probably 90% of the infrastructure.
So basically, we’re going to more than
double the value of coral reefs
if we include coastal protection.
And so let’s think about some of the
other things we can do with these tools.
So we’re modeling
flooding along the coast.
And so I’m just showing you
our same kind of return period.
I’m showing you current reefs, future
reefs, and whichever our metric is here.
But say – let’s talk about
coral reef degradation.
Like, climate change,
land use practices, sea level rise.
Well, that’s going to
push that number up.
And now, again, we can – so if we
degrade the reef more at sea level,
and that flooding is further inland,
we can, again, use these same
data sets to quantify the dollars
and lives to say, what’s that value.
The other thing that’s really neat is
we can do the reverse of that,
is we can say, here’s the degraded reef.
If we increase the health of it,
that flood is going to be less –
the flooding is going to be
less far inland, and now we can –
we can count up, between the –
and the post-restoration.
And that’s the benefit
of that restoration.
And this is
becoming really exciting.
And, again, so that would
drag those values down.
And so now that area between the two
is the benefit of that restoration.
So the question is, is how does the U.S.
decide to fund post-disaster restoration?
Anyone? Because I had
zero clue about this myself.
Okay. So it’s FEMA’s BCA Toolkit,
or benefit-cost analysis.
Good way to
do a thing, right?
You know, value –
balance the benefit and cost.
And so it’s – in this case, you could
do the risk reduction versus the cost.
And the cost in this case would be –
coral reef restoration is about
half a million dollars to $3 million
per kilometer of shoreline.
Sounds like a lot
of money, right?
Does anyone know what a cost
of offshore breakwaters are?
Well, it’s an order of
magnitude higher than that.
I’ll just – sorry,
I’ll save you the suspense.
But, yes, it’s an order of
magnitude higher than that.
So what you really want is a
benefit-cost analysis greater than 1.
Really good projects are,
like, 5-to-1 or 10-to-1.
But you need to be able to
quantify both sides of that.
Well, we already know
the cost of restoration.
Well, now we can
do risk reduction.
However, the U.S. Office of
Management and Budget’s
Circular A-94 and the U.S. Stafford Act
says this has to be done at a
spatial resolution and economically
rigorous manner – certain degrees.
Well, we’re sure doing it
at spatial resolution.
And, well, FEMA just determined
we meet those needs.
So this model framework we’ve
developed is rigorous enough financially,
rigorous – or, spatially fine
enough to really meet those needs.
And so, what that says is, you know,
all these tools that they use to fund
gray infrastructure –
seawalls, breakwaters, and stuff –
we can use it fund
And like I said in
the previous slide,
green infrastructure is an order
of magnitude less costly.
And provides those other
things like tourism, fisheries.
And so Lloyd’s of London –
folks have probably heard of them –
big insurance people – they actually
put together a document kind of saying,
okay, well, what are the different things?
And you can do pre-disaster funding.
You know, things like the Corps of
Engineers, FEMA pre-disaster mitigation
grants, post-disaster funding – these
flood mitigation assistance programs.
Something that’s happening right now in
the Caribbean following the hurricanes.
And they also break out, like, who pays
versus, you know, who benefits from this.
Well, again, so now, these are all funds
that theoretically can be tapped into.
And we do two –
how do you restore a reef?
Well, there’s two things.
One, you can do structural.
These are basically concrete balls
called reef balls that can be
dumped out on the seafloor
to increase the water depth.
And then new corals land – recruit
to them and grow through time.
And they’ve got all these nice holes
in them, so fish like to hide in them,
and they’re really good.
But they cost something, right?
The other thing is NOAA’s
Coral Reef Restoration Center.
And a lot of governments in the Caribbean
and the Pacific and the Indian Ocean –
foreign governments actually
have their own coral nurseries.
So you can not only put the structural
feature out, and we can model that
structural feature by the
decrease in water depth.
But we can also measure the
increased roughness of those corals.
So we can quantify the hazard risk
reduction and the resulting cost in
dollars and – or, savings in dollars
and lives of both the structural
restoration and the
And then do those benefit-cost
analysis for both of those.
This is all great in theory, but sadly, the –
Hurricane Irma and Maria tore through
the Caribbean causing billions
and billions of dollars in damage.
Well, we had already set the
model up for these areas for, you know,
the coral reefs, the – reduced the
annual damage and the people flooded.
And, again, so we could flip this
model around, and so we could
take the – well, in this case,
it would be the existing reef,
put the restored reef on top of it,
and have that reduced.
So to basically guide, where can they
do restoration to reduce coastal hazards?
And we now have a proposal in to
do this with Puerto Rico and the
U.S. Virgin Islands to basically guide
restoration to reduce coastal hazards.
So we can improve the health
of the ecosystem, increase fisheries,
and do it to reduce coastal hazards,
and in an
economically beneficial way.
So where can this lead us?
Now, this is exciting stuff,
and you people are all
probably an order of magnitude
more financially savvy than I am.
But Mike Beck and
The Nature Conservancy is really
trying to say, what’s the next step in this,
is remember, we talked about how
there’s these mechanisms to fund it.
Well, the first one’s insurance.
And what one can do is fund restoration
of damaged reefs using insurance.
You could set the
rates to promote protection.
And this is something that The Nature
Conservancy is working with Swiss Re.
Now, if you don’t know Swiss Re,
Swiss Re is – they’re the insurers
of the insurance agencies. So they’re
in the billions to trillions of dollars.
Like, and so when you
start to get those folks on board,
all the little State Farms and
stuff like that kind of will follow.
The other is – another example
is resilience infrastructure bonds.
And so they can support
pre-reef restoration based on
this projected hazard risk
They can also pay for defense through
the reduced cost of insurance bonds.
And this is something
they’re doing with Munich Re.
Now, I believe Munich Re
is so big that they insure Mexico.
So, again, large-scale.
So really what they’re doing – and this,
again, is The Nature Conservancy
and Munich Re and Swiss Re,
is really a resilience insurance solution
that overcomes the tradeoffs between
risk reduction and risk transfer.
So you have this upfront reef
restoration investment that reduces risk.
impact reduces premiums,
and that’s an incentive that’s created
for restoration and risk transfer.
So here shows current coastal funding
for conservation and infrastructure.
Over the first
15 years of the century.
So this is dollars spent.
And you see what
goes into biodiversity aid,
like coral reef restoration
and things like that.
You go over to
the other side of here.
Insured losses is over a
quarter of a trillion dollars.
So using these mechanisms with –
well, the re-insurance industries,
the insurance industries,
what we’re looking to do is
see if somehow we could get
a little of that money coming
out of the insured losses,
put it into biodiversity aid to
reduce that overall large damage.
So the implications – well, again,
there’s private incentives,
such as insurance
and resilience bonds.
Public incentives are these
pre-disaster green bonds and
special purpose tax districts,
post-disaster FEMA restoration funds.
But the big thing is this prioritization
of natural infrastructure and policy.
FEMA’s starting to buy in on this.
Hopefully next we can get the Corps.
Because we’re doing it
to save dollars and lives.
So in summary, coral reefs
are our first line of defense.
We can accurately and
rigorously account for
the defenses the reefs provide.
We can generate value-based
information to guide restoration
and increase – efforts to increase
the resilience of coastal
communities and ecosystems
at management-relevant scales.
And that’s really important.
And so, you know, the push now – not
by us at the USGS, but our colleagues,
to get the nature included
in these industry risk models.
Because people are going to make the
right decision when the industry –
insurance industry says, we’re not
going to insure that, not going to build it.
And that’s where I think we’ll
start to get to really smart growth.
So we’re trying to link
coral reef ecosystem health
to coastal hazard risk reduction.
And that’s to reduce risk,
increase coastal resilience, and better
direct reef restoration efforts.
Thank you very much, folks.
- Thank you, Curt.
So now it’s time for questions.
And, as usual, we’ll ask you to go to the
two microphones that are already set up.
Or, if you’d like,
I can bring you this handheld mic.
- So is there any breeding of higher-
temperature-resilient coral being done?
- Yes, there is.
I cannot remember – it wasn’t
the government that funded it,
and I don’t want to say it’s, like,
Elon Musk or – it was –
it was a private group that funded it.
And it’s what they
call the Coral XPRIZE.
And what they’re doing is,
they’re doing – they’re basically
going out and trying to find
corals that live in really extreme
high-temperature environments –
places on the island of Ofu
of American Samoa go up to,
like, 35 degrees C every day.
Places in the Arabian Gulf.
And saying, gosh, these ones
are predisposed to be able to
handle those high temperatures,
and trying to breed those.
Now, obviously, when you
start breeding select groups,
you decrease biologic diversity.
You may – potentially susceptibility
to disease and things like that.
But they’re doing that.
They’re doing it – and I can’t remember
where in Australia, but they’re
doing it at the University of Hawaii’s
Hawaiian Institute of Marine Biology
on Coconut Island off Oahu.
So that’s Ruth Gates and others are
basically trying to breed super corals.
- You were talking about
the restoration of reefs.
- Is there a point of no return,
where a reef – collection of
reefs can no longer be restored?
And, as a follow-up to that, are we at
that stage for the Great Barrier Reef?
- Okay, so the first question,
can reefs hit a point of no return? Yes.
We’ve seen certain places in Hawaii
where there was really poor agricultural
practices – primarily sugar and
pineapple – where so much sediment
ran off the islands for a hundred
years that the reefs died,
and they created so much sand
that there was no more hard ground.
Corals need to settle on hard ground
to grow. They can’t land on sand.
And so what we call it is a phase shift.
Like, it’s shifted to sand,
and it’s not going to be reef again.
So that can happen.
Has the Great Barrier Reef
hit that point?
[chuckles] There’s a lot of biologists
and ecologists that would argue that.
I’m a geologist, and I’ve looked –
I’ve had colleagues and others that
look at history and say corals have been
around for a quarter of a billion years.
They’ve gone through
some pretty bad things.
They’re going through
bad things at a lot higher rate.
But there’s going to
be some refugia in some places
where they’re going to
make it through.
Are the reefs going to look like they
look like today? Probably not.
And we’re going to lose a lot of those
ecosystem services along the way.
But do I think corals, as a – oh, gosh,
I don’t know if it’s a – it’s not a species.
It’s a genera or somewhere in
that phylum kingdom thing.
I’m sorry. I’m a geologist.
You know, we’re not – they’re not
going to go extinct. Some species may.
I will say this, is one of the big problems
with restoration historically is they’ve –
in those coral reef nurseries, they’ve
found really fast-growing corals.
Because, man, it makes you feel good
when something grows fast, right?
Like, in your greenhouse?
However, the corals that grow
really fast, they pour everything
into growing fast, and they’re really,
really not robust and resilient.
And, I mean, not really, but –
like, these are the kind of things,
you sneeze on them, and they die.
And what they’ve really done is looking
to shift the corals – and this has only
happened in the past couple years.
Because, we’re, like – I hate to say,
some of the geologists came and
would be, like, that species is –
you know, you look through
the geologic record and, like,
anytime there’s a slight change
in the climate, man, those things go.
They go. They go.
And sadly, some of the main
coral species that the U.S.
has put on the threatened and
endangered species list are those corals.
Acropora. Acropora is this general –
they look beautiful. They’re out there.
I mean, the geologic record,
something happens, they’re gone.
They’re gone. They’re gone.
And they want to breed those because,
you know, they make you feel good,
and they’re a threatened
and endangered species.
However, they’re not really robust.
ones are the hardy ones.
And so, at least in
a lot of these nurseries,
they are moving towards
those more robust species.
And, I mean, obviously, you want –
you want a diverse group to
keep biodiversity up, but they’re
realizing that, gosh, you know.
The other problem is, in a lot of places –
like, hey, when there’s a vessel
grounding or a hurricane –
like, Irma came by and destroyed
acres and acres of reefs in the Keys.
Okay, you can put corals back there.
But in a lot of these areas where it’s
wastewater discharge that’s killed
the reefs, or land-based pollution
that’s killed the reefs, are you going to
take a new canary and put it back in
the same coal mine that killed the
last canary? And sadly, that’s
what’s happened in a lot of cases.
And so, they’re trying to be a little
smarter about, okay, well, you know,
a vessel grounding site’s a
great place to replant corals.
But in a lot of these places, they’re being
stressed by other factors, and us putting
coral replants, or transplants, in there
is just going to have them die.
So we need to better
manage those things.
The nice thing –
oh, I shouldn’t say the nice thing,
but the thing about land-based sources
of pollution, these can be solved
locally at a jurisdiction level,
at a state level, at a territory level.
And we can hopefully reduce
those stressors to hopefully
make those corals a little more resilient.
Because the global stressors are the ones
that we can’t stop in Hawaii, in USVI,
in Puerto Rico – the increased
temperatures that can cause bleaching,
and the increased ocean acidification.
But at least, if we can
reduce land-based pollution,
we can remove
that one stressor.
- Oh, sorry. He’s leaving. Yes, ma’am?
I have a couple of questions.
One is, like, you did all these
calculations. Did you test
against the real data?
- Oh, yes. Because I always say,
I can make a model that shows
purple elephants fly. But that’s
one of the things we’re good at.
And we’re – I mean, I shouldn’t –
I wouldn’t say we’re forced to,
but that’s one thing we do is
we have to prove our models work.
And so we’ve run these –
the flooding models in certain locations
to see that they’re doing accurate –
because if you can’t model the
present and do it right with data,
to do any projections, I mean,
then you’re out of your mind.
Sadly, it happens.
I will say here at the USGS, though,
we have to go – undergo peer review.
So we have our colleagues look at it,
and they’ll call horse doody …
- Yeah, the reason I’m asking
is that you didn’t show it.
You showed the predictions, but not
how did it test against the real data.
And I was looking for it.
- Okay. Well, I’ve got – trust me,
I’ve got a bazillion [inaudible] …
- No, I’m not saying –
I’m not questioning.
I’m just saying …
- I just didn’t think that was
going to be the most exciting thing
to show you folks.
- Oh, okay.
- There’s a lot more even –
I mean, that was enough sausage,
I thought, for most people.
And I was kind of trying to
limit what I was showing you.
But, yes, it has been calibrated
And it’s actually been peer-reviewed
and published, this methodology.
- And the – another question
I have is the restoration.
- Do you – are you assuming that
all the coral reefs have been damaged?
Or it’s just specific areas
which may require restorations?
And then, also, as you mentioned,
there were these local policies and
practices versus the global practices,
which are impacting the coral reefs.
- I’m not going to remember the –
that’s a real long discussion.
Can I go to the one at a time?
You were asking about the coral reef?
I have a short attention span.
I’ll get lost there.
So the first was asking about restoration.
Well, what we know is, already,
in some places, that there are – I mean,
this is zero to 10% live coral coverage.
So, as of right now,
maybe we could restore these
and bring them up to
40% live coral cover.
However, when you’re asking in other
places, like in Florida, Puerto Rico,
USVI, NOAA’s Coral Reef
Conservation Program went out
and did 300, 400-some site visits and
noted the degree of coral damage.
So that we know – and they’ve
recorded that, so we know that,
okay, there was 30% live coral,
and now it’s down to 5%.
So we have data on that to say –
so then, what we can do is say, okay,
we’re going to take – say this is a map –
this is a map after the damage.
Okay, this is all now
5% live coral coverage.
Let’s make it 50% live coral
cover and run the model on it.
So that’s how
we’re doing that part.
Sorry, please, now you
can ask your question.
- No, so my next question was that,
how you’re going to reduce
the local practices to –
so when the restoration is done,
that the restoration stays
there and not degrade again?
- Well, again, some of the places
it’s been – right now, the only place
we’re doing restoration – we’re trying
to model to guide restoration is in those
areas impacted by hurricane damage.
So those were, in some – most cases,
relatively healthy reefs not
impacting by land-based pollution.
Some of those are, though.
And that’s a very important question is,
okay, well, this is a degraded –
this was a storm-impacted reef,
but it was already degraded.
So – well, first off, the USGS,
let me stress, does no policy.
We provide science to make other
people make decisions –
or, make better-informed decisions.
So them knowing that, hey,
that water quality is already violating
the Clean Water Act or something,
that’s something that EPA or
someone else needs to step in and say.
So we can’t guarantee it.
We don’t do the restoration.
We don’t make the decisions
to do the restoration.
We provide the science so that they
can make a better-informed decision.
But they’re going to be –
have that knowledge of, okay, this area
is not impacted by land-based pollution.
Got trashed by a hurricane.
If we restore it, here’s our benefits.
We can say, hey, we can restore this one,
and this would be your benefits.
But [chuckles] you might have
less successful restoration,
or at least the biological
or ecological restoration.
We still put those big reef balls out
and help reduce the wave energy, but –
so there’s a lot of information, and all
of that information comes from us,
and there’s a lot of local management
decisions that need to be made.
- Thank you.
- Yeah. No worries. My pleasure.
- Okay. Well, maybe that’s it.
- Thank you very much
for coming folks.
We really appreciate it.