More than 80% of the world’s freight moves by ship. Despite their crucial role in the global economy, few seaports are preparing for the impacts of climate change, including rising sea levels and more frequent storms. Photo: Port of Los Angeles |
The majority
of seaports around the world are unprepared for the potentially damaging
impacts of climate change in the coming century, according to a new Stanford Univ. study.
In a survey
posed to port authorities around the world, the Stanford team found that most
officials are unsure how best to protect their facilities from rising sea
levels and more frequent Katrina-magnitude storms, which scientists say could
be a consequence of global warming. Results from the survey are published in
the journal Climatic Change.
“Part of
the problem is that science says that by 2100, we’ll experience anywhere from
1.5 to 6 ft of sea level rise,” said the study’s lead author, Austin
Becker, a
graduate student at Stanford. “That’s a huge range.”
Port
authorities, like many government agencies and private companies, have to make
tough financial decisions when it comes to funding infrastructure, he said.
They need accurate information from scientists about what to expect, so that
they can plan accordingly. Building a structure to withstand a 6-ft sea level
rise would cost much more than trying to accommodate a 1.5-ft rise, said
Becker, a doctoral candidate in the Emmett Interdisciplinary Program in
Environment and Resources at Stanford.
In 2009,
Becker distributed 160 surveys to members of the International
Association of Ports and Harbors and the American Association of Port
Authorities—the
first worldwide survey of port authorities to address climate change
adaptation. A total of 93 agencies representing major seaports on every
continent, except Antarctica, responded. The
majority of respondents ranked sea level rise and increased storm events
associated with climate change high on their list of concerns. However, only 6%
said that they intend to build hurricane barriers within the next 10 years, and
fewer than 18% had plans to build dikes or other storm protection structures.
“As we
saw with Katrina in 2005, storm and flood damage can devastate a regional
economy for years after an event and have national impacts,” said Becker.
Katrina, a Category 5 hurricane, caused an estimated $1.7 billion of damage to Louisiana ports. This
month, the region is bracing for flood damage once again, as the National
Weather Service is
predicting that the Mississippi River could crest in New Orleans on May 23.
And with scientists forecasting a doubling of Category 4 and 5 hurricanes in
the Atlantic Ocean by 2100, it seems all the
more imperative to start thinking about adapting port infrastructures now, he
said.
Threat of violent storms
Sea level
rise and more frequent violent storms resulting from climate change threaten to
take a tremendous toll on all types of infrastructure—especially along the
coasts, said study co-author Martin Fischer, professor of civil and environmental
engineering and director of the Center for Integrated Facility
Engineering at
Stanford.
Fischer,
Becker and a group of Stanford engineers are developing computer models to help
port authorities and other government agencies make more informed decisions
about adapting to climate change as they plan for the next generation of
infrastructure. The group meets weekly at a seminar that focuses on engineering
and policy for a sustainable future.
“Look
around at any seaport today and you will see structures that were built 100
years ago,” said Fischer. “And the buildings that we are building
today will be around when sea level rise begins to reshape the coast.”
The problem on
a global scale, he said, is that ports may start scrambling all at once to
adapt their structures to changing environmental conditions. “It could
potentially exceed our capacity for construction worldwide,” he added.
Fischer and
his colleagues have developed a model that demonstrates how a rapid,
simultaneous push to fortify the world’s seaports could drive up demand for
construction materials and equipment. The model, called Sebastian, uses a
Google Earth platform to simulate the costs and time required for building
dikes around 200 of the world’s most active seaports. Sebastian knows the shape
of the ocean floor at each location and tailors the structure to each site to
produce an estimate of the materials, labor and equipment that would be needed
to fortify the port against sea level rise.
“Sebastian allows us to run different scenarios based on different
levels of sea rise, and see how the ports are affected,” said Fischer.
Using criteria in the Army Corps of Engineers manual, the model calculates the
resources needed for each variation of the structure. It’s a way to calculate
big-picture, worldwide demand, Fischer said, but it also gives managers more
reliable information about how much survivability they are buying when they
invest in different types of protective structures.
Lack of oversight
Another
difficult challenge in preparing for climate change at seaports is that no
single agency or individual has sole authority over any given port, according
to Becker. Some ports are privately owned, some are public and some are a mixture
of both. And a broad range of entities—from transportation companies to
insurance companies to the Environmental Protection Agency—have some stake in
how they are managed. The arrangement greatly complicates ports’ efforts to
budget and plan for the future, according to the study.
But plan they
must, said Fischer.
“By the end of the century, quite a few ports will be in trouble, even
if you are using the most conservative estimates for sea level rise,” he
said. “And if you use the estimates at the top of the range, all of them
will be in trouble.”