It’s happening now and will
accelerate
Rising levels of greenhouse gasses are
increasing global temperatures and this is causing sea levels to rise.
Global warming causes sea levels to rise
by melting ice sheets, glaciers, and sea ice; it also causes water to warm and
expand. Sea-level rise and resultant flooding may be the greatest challenge
facing humanity.
Scientists agree that sea levels will
rise and much of the most recent research suggests that this rise will be larger and faster than
originally thought.
Many of the world’s greatest cities
including Manhattan, London, Shanghai, Hamburg, Bangkok, Jakarta, Mumbai,
Manila, and Buenos Aires are expected to be inundated by rising seas.
Tidal floods interfere with transportation,
inundate roads, destroy homes, damage cars, kill forests, and poison wells with
salt. Moreover, the high seas interfere with the drainage of storm water.
The seas are on average around 9 inches
higher than they were before the Industrial Revolution. We now have 408 parts
per million of CO2 in the atmosphere and growing. Our current trajectory
translates to 120-190 feet of sea level rise over the long term.
More and faster
The world is getting warmer and this
heat is causing more thermal expansion. Sea level rise is also caused by the
melting of the world’s two largest ice sheets, on Greenland and West Antarctica, as
well as mountain glaciers worldwide.
Most studies suggest that sea levels
will rise by about three feet, but these studies have not adequately measured
the contribution of melting ice from Greenland and the Antarctic ice sheet.
Greenland alone is losing 215 gigatons
of ice per year; that is equivalent in weight to 100 times all the cars on the
planet.
As reported by Angela
Fritz in
the Washington Post, a new study published in the Journal Nature shows that on
its own, the melting of the Antarctic ice sheet could double sea level rise.
Using the IPCC’s “Business as Usual” scenario, oceans could rise by
almost 2 meters or more than six feet by the end of the century. By 2500, we
could see the sea level rise by more than 13 meters (42 feet). Such an increase
in sea levels will have civilization changing impacts all around the world
including the US.
By 2100, Miami and New Orleans will be
under water. By 2500, states like Delaware would be almost entirely submerged
as would the southern coast of Florida, California’s Central Valley,
Sacramento, San Francisco Bay, Boston, Washington DC and much of Manhattan and
Brooklyn.
An ABC
News article corroborates
this view, citing research from renowned climate scientist James Hansen which
indicates a doubling of the speed at which sea level rise is occurring.
A study from the U.S. Geological Survey found that half of the U.S. coastline
is at high or very high risk of impacts due to sea level rise. Around the
world, the majority of human habitation is concentrated along coastlines. This
means that billions of people could potentially be displaced.
“Accelerated sea level rise is real, and
it’s ongoing, and it’s not something we should doubt,” said John
Fasullo, a climate scientist at the National Center
for Atmospheric Research in Boulder, Colorado.
A study
led by Rutgers University shows that sea levels are rising
faster than any time in the past 2,800 years. The study examines historical sea
level rise and shows that our oceans are rising at an ever increasing rate.
To
illustrate what this means in practical terms, look at the rate of flooding in
Annapolis, Maryland. The tide gauge at Annapolis recorded 32 days of flooding
from 1955 to 1964, while that number spiked to 394 days in the decade from 2005
to 2014.
As reported by Don
Jergler in
the Insurance Journal, at the annual RIMS conference last spring, an official
with the National Oceanic and Atmospheric Administration (NOAA) indicated that
sea levels could rise by much more than originally anticipated, and much
faster.
The most recent data translates to sea level rises that are far worse
than IPCC predictions. This new data suggests that sea levels could rise by
roughly 3 meters or 9 feet by 2050-2060, far higher and far sooner than current
projections.
By 2050, a total of 26 major US cities
may find themselves struggling to manage rising seas.
Present day reality
Sea level rise is not just some abstract
future possibility; it is already happening. As explored in a study published
in Environmental
Research Letters, there are at least five reef islands
in the Pacific that are already inundated, and they serve as a warning for the
world.
Five Solomon Islands are gone, washing
away the homes of the people who lived there. At least six more islands
are severely eroded. While the global average annual sea level rise is
about 3 mm per year, in the Solomon Islands, the rate of increase is around
7-10 mm per year since 1993.
By 2100, 13 million people will be
displaced in the U.S. alone. As reported in the Green
Market Oracle, flooding is also a modern day problem
in the US. Residents of Chesapeake Bay’s Tangier Island are expected to become
climate refugees in a few decades.
The village of Kivalina, in northwestern
Alaska, will be under water by the year 2025. A total of more than 180 villages
are already feeling the impacts from rising seas. The Yupik community of
Newtok is expected to be completely under water by 2017.
Rising seas are already forcing people
out of their homes in the bayous of Louisiana, about 80 miles southwest of New
Orleans. The Isle de Jean Charles is disappearing into the rising waters
of the Gulf of Mexico, forcing many of its residents to flee.
As explored by Justin
Gillis in
a New York Times article, sea level rise is already impacting U.S. coastal
areas. He lists dozens of places where we are already seeing the impact of
rising sea levels; this includes Fort Lauderdale and the only road to Tybee
Island, Ga.
“Once impacts become noticeable, they’re
going to be upon you quickly,” said William V. Sweet, a NOAA scientist. “The
[flooding] trends are all very clear. They’re going up, and they’re going up in
many of these areas in an accelerating fashion.”
The West Coast of Oregon and California
can expect to suffer the worst impacts of rising seas.
Along the East Coast, NOAA scientists
say that many communities have already, or will soon, pass a threshold where
flooding starts to happen much more often. In southern Louisiana and the entire
Chesapeake Bay region, including Norfolk, flooding is expected to be severe.
Seas will keep rising
Even if we engage in serious global
emissions reduction efforts, sea level rise is baked into the system. As
reviewed in a study of past sea level changes published in Science,
coastal communities may face rises of at least six meters even if we limit
global warming to 2C.
A rise of at least 15 or 20 feet has
already become inevitable. This data pours cold water on the hope that
mitigation efforts alone could stop the seas from rising. It is clear that we
will also need to invest in adaptation to manage inevitable sea level rises.
The economic
costs of
sea level rise are already staggering, and these costs will continue to accrue.
The only sane response to scientific predictions about sea level rise to
aggressively engage in both mitigation and adaption
efforts.
Sea level rise could be far worse than
even the dire scientific predictions cited above, as these studies do not take
into effect the massive amount of GHGs that could be unleashed by melting
permafrost.
Together, the data convincingly shows
that we need to do what we can to advance both mitigation and adaptation
efforts. This means we need to curb fossil fuel usage and other man-made GHG’s.
We also need to invest massively in adaptation efforts to prepare for
inevitable sea level rise.
Richard
Matthews is a consultant, eco-entrepreneur, green investor and author of
numerous articles on sustainable positioning, eco-economics and
enviro-politics. He is the owner of The Green Market Oracle, a leading
sustainable business site and one of the Web’s most comprehensive resources on
the business of the environment. Find The Green Market on Facebook and follow The Green Market’s twitter feed.