Year: 2008
Type: book-chapter
Abstract: The physical configuration of coastal ecosystems is determined by a combination of marine, terrestrial, and atmospheric processes that shape the land/ocean interface.As the world's present coastlines evolved over the past 7,000 years (a period when sea level was relatively stable) assemblages of organisms that represent the current biodiversity of the coastal margins of the Americas also emerged.Located along the narrow transition zone at the ocean edge of continents and islands, coastal ecosystems and their biodiversity are affected by changes in the processes that created and sustain them.They are intrinsically dynamic due to their exposure to alternate flooding and drying, winds, waves, tides, and storms.Organisms that inhabit coastal ecosystems are uniquely adapted to environmental conditions that occur along the energy, salinity, and moisture gradients that extend from the subtidal region of the coast to the inland boundaries of its wetlands, estuaries, and floodplains.Impacts on coastal systems are among the most costly and most certain consequences of climate change.As temperature increases and rainfall patterns change, soil moisture and runoff to the coast are likely to be altered.As sea level rises, coastal shorelines will retreat and low-lying areas will tend to be inundated more frequently, if not permanently, by the advancing sea.The salinity of estuaries, coastal wetlands, and tidal rivers will increase, thereby restructuring coastal ecosystems and displacing them further inland.If tropical cyclones increase in intensity, as projected by many studies, shoreline retreat and wetland loss along the low-lying coastal margins will accelerate further.As temperature increases along polar coastlines, a combination of permafrost thawing, sea level rise, and sea ice retreat will cause coastal erosion and land loss.This chapter examines the known effects of these and other key climate change variables on coastal ecosystems and their biodiversity.The vulnerability of coasts to atmospheric warming and the changing climate is enhanced by environmental stresses associated with human development of the coastline and adjacent watersheds.Coastal areas comprise some of the most heavily developed landscapes in the Americas.The autonomous adaptive capacity and sustainability of coastal ecosystems in North, Central, and South America will be challenged due to a combination of stressors at the ocean/land interface.Coastal river deltas, such as the Mississippi and Paraná, are particularly vulnerable due to their high sensitivity to relatively small changes in mean sea level and riverine sediment delivery.Many coastal states, provinces, and nations are planning coastal adaptation strategies but much of the current emphasis is on protection of the built environment.Some climate change adaptation options, such as flood protection levees and sea walls, can exacerbate the effects of climate change and sea level rise on coastal flora and fauna.By incorporating biodiversity considerations into adaptation planning, native fish, wildlife, and plant populations are more likely to be preserved as climate change intensifies in the 21 st century.
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
SDGs: Climate action, Life on land
Open Access status: green
Funders: U.S. Department of Commerce, U.S. Department of Agriculture, Strong, Nature Conservancy, Royal Society, University of Cambridge, University of East Anglia, Climate Extremes, Directorate for Biological Sciences, National Oceanic and Atmospheric Administration, U.S. Geological Survey, U.S. Forest Service
OpenAlex ID: W1543223890