CLIMATE CHANGE AND OCEAN ACIDIFICATION - Marine Pollution: What Everyone Needs to Know - page 170

we were to follow the high emissions scenario of the IPCC, a
sea-level rise of 6.8 m could be expected in the next thousand
years. The two other IPCC scenarios project SLRs of 2.1 and 4.1
meters. Rising sea levels could make entire areas, even island
nations, uninhabitable or extremely vulnerable to flooding
and storms. Because of dense concentrations of humans and
development in coastal zones, many countries are vulnerable
to SLR and coastal flooding. Tens of millions of people around
the world are already exposed to coastal flooding from tropical
cyclones. Global warming has the potential to increase flood-
ing from more severe hurricanes and sea level rise. Developing
countries, particularly small islands and low-lying areas, are
especially vulnerable and have limited capacity to adapt to
rising sea levels or to recover. Low-lying areas in developed
countries such as Long Island, New York and South Florida
in the United States are also at great risk. Coastal populations
are particularly vulnerable to natural disasters including tsu-
namis, floods, and hurricanes. Since over a third of the world's
population lives in coastal zones within 100 kilometers (62
miles) of the shore, the effects could be disastrous. According
to IPCC, many millions more people will be flooded due to
SLR by the 2080s.
SLR affects natural intertidal ecological communities such
as salt marshes and mangroves at the edge of the water. These
communities will have to migrate inland or increase their
elevation in order to avoid being submerged by rising seas.
As these are important habitats for birds and marine animals
that use them as nursery habitats, many species are at risk if
these wetlands cannot either migrate inland or increase their
elevation. In many areas, marshes are not expected to be able
to increase their elevation fast enough to keep up with SLR.
However, if storms transport new sediments into the marshes,
they may be able to increase elevation and persist for a longer
time. In developed areas there are roads, houses, and other
man-made structures just landward of the marshes, which
prevent them from migrating inland.