Coastal dwellers should be somewhat anxious about the reality of rising sea levels. Recent data suggests that the seas have risen and will continue to rise at a steady pace over the next century. In the past technology was not available to measure sea levels, consequently little consideration was given to the effect that sea levels have on coastal populations. With the ability to collect accurate data, impact can now be projected on a year to year basis. Evaluation of the data provides essential information to direct the future planning of coastal populations.
Land Mass Decrease
As sea levels rise, the logical result is the decrease of land mass. Water slowly erodes and floods existing dry land. This narrows the beaches and moves existing populations closer to the sea. Although sea levels may rise inches annually, over a long period, inches quickly become feet and land mass disappears.
Compromise of Wetland Areas
Wetlands provide essential buffers to the mainland from the sea as well as filter contaminants being brought to the sea from the wetlands. This natural barrier also keeps salt water from becoming too invasive on freshwater sources. Rising sea levels often overtake existing wetlands. Because of burgeoning coastal populations, wetlands are unable to migrate further inland. Instead, barriers are constructed to preserve coastal populations, prohibiting the natural process of wetland migrations. Without natural barriers, flooding becomes a much greater threat
Effects on Populations
Sea levels rise and the ensuing effects on nature lead to increased challenges and threats to those living in coastal regions. According to one source, seventy-five percent of Americans live in a coastal region (http://www.oregon.gov/DSL/SSNERR/docs/EFS/EFS39risesea.pdf). With a projected sea level rise of ten to fifteen inches by 2025, the possible impact on the population is tremendous.
Increased risk for flooding
The rise of sea levels greatly enhances the possibility of severe flooding. While living by the sea includes many privileges, it also exposes many risks. As wetland areas decrease and man-made barriers continue to be thrown up, the risk for flooding becomes a greater reality.
Decreased water supply
Water sustains life. Rising sea levels create a crisis for coastal populations by potentially decreasing the drinkable water supply. Combining the reality of rising sea levels to the fading wetland areas produces a scenario that allows increased salinity to present freshwater sources. Many coastal populations draw from freshwater sources scarcely separated from salt water. As sea levels rise, the very life-sustaining source of water may become scarce.
Sea levels do not arbitrarily rise on their own. The most visible contributing factor is the melting of glaciers and ice caps due to increasingly rising global temperatures. These ice masses slowly contribute to the sea level, forcing coastal populations to make decisions regarding how to deal with the realities. Because the main contributor is temperature, all projections are subject to annual review and consideration. Making dogmatic predictions is impossible. http://www.epa.gov/climatechange/effects/coastal/
Coastal populations do face significant risks due to rising sea levels. Being aware that the risk exists and knowing the contributing factors facilitates educated planning and understanding how to best steward opportunities for coastal development.