Geoscience Reference
In-Depth Information
large numbers of people to coastal regions for tourism and recreation. Native peoples are also dependent on
these resources for preserving their culture and traditions. Threats to these resources have economic and cul-
tural consequences for coastal communities.
The U.S. Global Change Research Program has predicted a rise in precipitation of as much as 25 percent by
2100, with increased flooding from storms, rising sea levels, and coastal land loss. The transportation, commu-
nication, energy, water, and waste disposal systems of the major Northeast cities will all be put at risk. Sea
level rise will also exacerbate stresses to estuaries, bays, and wetlands from increasing pollutants, temperature,
and salinity. Additionally, sea level rise will allow storm surges to reach farther inland, and climate change
could cause an increase in the intensity and frequency of storms in the Northern Hemisphere. Low-lying is-
lands could be submerged, and areas where human infrastructure prevents landward migration of coastal eco-
systems will be at particular risk.
Plans to protect ecosystems and habitats will include upgrading sewage treatment and stormwater runoff
systems and protecting wetland habitat. In order to mitigate the impact of climate change on marine ecosys-
tems and the people and communities who rely on them, monitoring programs to assess changes in the status
of migratory fish, invasive species, harmful algal blooms, and other coastal resources will have to be deve-
loped and maintained.
The Northwest Atlantic ecosystem is being altered both by top-down forces, such as overfishing, and
bottom-up factors like climate change. Some of the changes observed would likely have happened even
without the added stress of overfishing and are likely to increase in the 21st century, even if greenhouse gas
emissions are controlled. All marine life will be dramatically affected by the changes already set in motion. Se-
abirds and cetaceans are two prominent groups, besides fish populations, that are likely to be affected and, in
some cases, already have been. The warming atmosphere will cause an accelerated rate of rise in sea level by
melting ice caps, which will pour more meltwater into the oceans, and through thermal expansion of the water
column itself. Together, the changes are projected to cause a global increase in sea level of 1 meter (3 feet) by
2050.
