Dr. Peter Edmunds: Coral Reefs and Climate Change

Uploaded by CalStateNorthridge on 02.07.2010

Dr. Edmunds: The significance of coral reefs is really tremendous on a global scale.
There's no other habitat in the world, perhaps other than tropical rainforests,
that has more animals and organisms per individual area than coral reefs.
My name is Peter Edmunds. I'm a professor at California State University, Northridge.
We're on the north coast of Moorea, right next door to Cook's Bay,
and this is an island in the South Pacific Ocean. It's a tropical location.
It's very pristine, relative to a large number of locations, and it provides a
perfect spot to study the long term dynamics of coral reefs, where the impacts
from human events are relatively small, although they're not completely absent.
A large part of my responsibilities here in the Moorea LTR Project is
understanding how the corals and coral communities themselves are changing.
And I'm sure many folks have the sentiment their parents talk about how
the hills were greener, the trees were taller when they were children.
And that sentiment is exactly what we're trying to get at, but not to have it
as a general conversation of "I remember how it was many years ago,"
but we're trying to collect the information that shows clearly what the reefs
look like in 2005, in 2006, and of course in 2030 we want to look back and
see exactly what those reefs looked like. Now to get to that point
a large portion of my daily work here is going out on the reef in small boats
with a team of graduate students, maybe four or five people.
And we have six sites set up around the island of Moorea, and at
every one of these sites we have areas marked with stainless steel poles
and hopefully will last for 30 years as well, and each one of those areas
becomes a photograph in our record. We travel with a high resolution
digital camera, such as a serious professional might buy in a store.
We have that camera attached to a frame that we made in our own workshop,
and that frame supports the camera above the reef so we can take
exactly the same picture year after year after year. We typically go out to our
study sites. We work at about 60 feet and 30 feet, and at every one of these sties,
we're talking 40 or 50 photographs that have high resolution and allow us to
in our laboratory back in California to measure exactly how much
of that reef floor was covered by coral when we took that picture.
The other half of what I am trying to do here is experiments on the shore
where we build ourselves this aquarium facility that allows us to control the
temperature of sea water. And we'll be growing corals at different temperatures
to try to understand how winter cold temperatures, how summer hot temperatures
effect the success of individual species of coral. We're also doing experiments
where we are pumping carbon dioxide into some of our tanks.
Now carbion dioxide is one of the gases driving global climate change effects.
It's increasing in the atmosphere, and one of the critical questions
scientists would like to answer is how will corals be able to grow
at a time when carbon dioxide levels are much higher.
What we're trying to do is demonstrate clearly a cause and effect relationship,
that this temperature generally causes a coral to die, because that will
provide a true indication of how the reefs are responding and why
they are changing over time.
We want to know when we look back, and we're old scientists,
were the corals more abundant thirty years ago? Were they taller?
Were there more species? Without that information it's impossible to know
how things like climate change, how things like urban development truly are
effecting our reef, and it's impossible to have any degree of certainty as to
what that reef might look like for our children to swim over.