Why Are
Coastal Habitats
Important to
Carbon Storage?
When protected or restored, coastal
marine ecosystems absorb carbon and
store it for long periods.
When degraded or destroyed, these
ecosystems emit the carbon they have
stored for centuries back into the
atmosphere and oceans and become
sources of greenhouse gases.
These ecosystems also contribute to
healthy water quality, support fisheries and
buffer coasts against the impacts of floods
and storms.
Approximately one-third of the overall area
of coastal habitats has been lost in the last
50 years and the remainder is severely
threatened. Destruction of these
ecosystems means less carbon is stored
in surrounding sediment and the resulting
carbon emissions accelerate the rate of
global climate change. Major causes of
destruction of these systems include
draining or clearing for agriculture or
aquaculture, coastal pollution, and
unsustainable coastal development.
Oceans Store the Majority of Carbon
Oceans
Land Biomass
Atmosphere
93
%
5
%
2
%
Coastal Habitats Make a Major Contribution
to Carbon Storage
2
%
Coverage
50
%
Coastal habitats cover less than
2% of the total area of the ocean,
but account for approximately half
of the total carbon sequestered in
ocean sediments.
Carbon Storage
The degradation and destruction of
coastal ecosystems — mangroves,
tidal marshes and seagrass
meadows — can release up to 1.02
billion metric tons of carbon per
year. This is about 86% of the
carbon emitted by Japan in 2011,
which ranked 5th in the world for
CO 2 emissions. The estimated
carbon cost of these emissions can
be as high as US $42 billion.
30
%
Up to 30% of Coastal Habitats
Have Been Destroyed
This is an estimated average of
multiple data sets over time.
SOURCES:
Pendleton, L., D.C. Donato, B.C. Murray et al. 2012. Estimating global “blue carbon” emissions
OURCES:
endleton, L., D.C. Donato, B.C. Murray et al. 2012. Estimating global “blue carbon” emissions from
onversion and degradation of vegetated coastal ecosystems. PLOS ONE September 4, 2012.
uarte, C.M., J.J. Middleburg and N. Caraco. 2005. Major role of marine vegtation on the oceanic
arbon cycle. Biogeosciences 2: 1-8 (2005).
PCC. 2007. Climate change 2007: Working Group I: The Physical Science Basis. Figure 7.3 The
lobal carbon cycle for the 1990s. Intergovernmental Panel on Climate Change. Valencia.
affoley, D. and G. Grimsditch (eds). 2009. The management of natural coastal carbon sinks. IUCN,
Gland, Switzerland. 53pp.
Waycott, M., C.M. Duarte, T.J.B. Carruthers et al. 2009. Accelarating loss of seagrasses across the
lobe threatens coastal ecosystems. Proceedings of the National Academy of Sciences
06(30):12377-12381