Laboratory Manual for Introductory Geology 4e

FIGURE 17.1 Types of shorelines.
(a) Rocky shoreline at West Quoddy Head in Maine.
(b) Sandy and rocky shoreline, Hawaii.
(c) Coral reef along the Hawaiian shoreline.
(d) Salt marsh along the coast of Cape Cod, Massachusetts.
(e) Mangrove forest in northeastern Brazil.
(f) A seawall built at the southern tip of Manhattan (New York City).
Climate change has a profound effect on shorelines. During an ice age, as we’ve
seen, glaciers advance across the continents, locking enormous amounts of water in
ice that would otherwise have been in the oceans. Today, global warming is having
the opposite effect, melting the Greenland and Antarctic ice caps as well as most
mountain glaciers. And global warming isn’t just adding meltwater: as the oceans
get warmer, the water in the upper 700 m expands, a phenomenon called thermal
expansion. Between 1961 and 2003, thermal expansion accounted for about 25%
of sea-level rise. Between 1993 and 2003, that proportion had risen to nearly 50%.
17.2 FACTORS CONTROLLING SHORELINE FORMATION AND EVOLUTION
433