Land Loss and Displaced Population of the North Carolina Coast due to Predicted Sea-Level Rise

The land loss and displaced population of the North Carolina coast caused by predicted sea-level rise are quantified. Maps are created to show land area that would be inundated from four sea-level rise predictions. The predictions used are a sea-level rise in the year 2100 of 1, 2, 4, and 7 feet above the 1990 level. The land area and displaced population are calculated for each of the predictions. The results show that 18.1 percent of the land area and 143,068 people of coastal North Carolina would be inundated with a sea-level rise of 1 foot, 22.5 percent land area and 175,528 people with 2 feet of rise, 27.6 percent land area and 215,280 people with 4 feet of rise, and 34.4 percent land area and 272,223 people with 7 feet of rise. 1.0 Introduction Many scientists agree that climate change is one of the most pressing world issues. Of the many impacts that climate change has on the planet, sea-level rise could be one of the most detrimental to humans. According to McGranahan et al. [1], “2 percent of the world’s land area is less than 10 meters above sea level but contains 10 percent of the world’s population and 13 percent of the world’s urban population. ” Sea-level rise would have impacts on society through coastal erosion, increased susceptibility to storm surges, and groundwater contamination [2]. In addition to the impacts on humans, sea-level rise would also cause changes to near-shore coastal dynamics, including sand abundance and distribution and shipping channels. Sea level is defined as the average height of the sea with respect to a reference surface [3]. The sea level changes on a short-term basis due to waves, tides, storms, and seasonal weather patterns [4]. Long-term sea level change is dominated by fluctuations in global near-surface air temperature and fresh water input from ice sheets and glaciers. Of these contributing factors, ice sheets have the greatest ability to raise the sea level. The complete melting of ice sheets would raise the global sea level about 70 meters [5]. Over the last century, the mean sea-level rose 1 to 2 mm/year, with thermal expansion caused by warming contributing 0.5 ± 0.2 mm [2]. Thermal expansion is a change in the volume of ocean water in response to heat transfer with the atmosphere. Because the mean global surface temperature has increased 0.85°C from 1880-2012, there is a strong correlation between temperature and sea-level [6]. This increase in temperature has come as a result of the emission of greenhouse gases from human activities. Another concern with regards to ice sheet and glacier melting is soot. Soot is twice as effective as carbon dioxide when it comes to altering the global surface air temperature [7]. When deposited on snow and ice, soot decreases the average albedo of the earth and increases the amount of sunlight that is absorbed. The coastal region of North Carolina is one of the state’s most valuable resources. The beaches that line the Atlantic Ocean are popular vacation spots for people from around the world. The Cape Hatteras National Seashore on the Outer Banks of North Carolina received over 2.31 million visitors in 2013 (outerbanks.org). In 2012, the total revenue from tourism in coastal counties was over $2.91 billion (NC Department of Commerce, nccommerce.com). From the 2010 census, the total population of the coastal counties was 988,911 (US Census Bureau, census.gov). In order to manage this region of the state, the Coastal Area Management Act of 1974 was passed by the North Carolina General Assembly. This act created the Coastal Resources