Welcome to PAP/RAC Mediterranean Coastal Alert! This newsletter is regularly updated monthly. It contains abstracts of selected current articles and archives on various environmental themes, in particular those dealing with all aspects of coastal issues. The selection is made from the articles published in the leading international scientific journals. This newsletter is an excellent way of keeping you updated with coastal studies and processes.
In 2001, the U.S. Geological Survey began conducting scientific assessments of coastal vulnerability to potential future sea- and lake-level changes in 22 National Park Service sea- and lakeshore units. Coastal park units chosen for the assessment included a variety of geological and physical settings along the U.S. Atlantic, Pacific, Gulf of Mexico, Gulf of Alaska, Caribbean, and Great Lakes shorelines. This research is motivated by the need to understand and anticipate coastal changes caused by accelerating sea-level rise, as well as lake-level changes caused by climate change, over the next century. The goal of these assessments is to provide information that can be used to make long-term (decade to century) management decisions. Here we analyze the results of coastal vulnerability assessments for several coastal national park units.
Index-based assessments quantify the likelihood that physical changes may occur based on analysis of the following variables: tidal range, ice cover, wave height, coastal slope, historical shoreline change rate, geomorphology, and historical rate of relative sea- or lake-level change. This approach seeks to combine a coastal system's susceptibility to change with its natural ability to adapt to changing environmental conditions, and it provides a measure of the system's potential vulnerability to the effects of sea- or lake-level change. Assessments for 22 park units are combined to evaluate relationships among the variables used to derive the index. Results indicate that Atlantic and Gulf of Mexico parks have the highest vulnerability rankings relative to other park regions. A principal component analysis reveals that 99% of the index variability can be explained by four variables: geomorphology, regional coastal slope, water-level change rate, and mean significant wave height. Tidal range, ice cover, and historical shoreline change are not as important when the index is evaluated at large spatial scales (thousands of kilometers).
Keywords: Shoreline change; Geomorphology; Tidal range; Mean annual ice cover; Mean significant wave height; Relative sea-level rise; Lake-level change; Coastal slope; Coastal vulnerability index; National Park Service; Great Lakes.
Source: Pendleton, E.A., Thieler, R.E., Williams, J.S. (2010), “Importance of coastal change variables in determining vulnerability to sea- and lake-level change”, Journal of Coastal Research: Vol. 26, No. 1, Pages 176-183; Received: 31 October 2008; Accepted: 4 November 2008; Published Online: January 2010, under DOI: 10.2112/08-1102.1.
Integration of impacts of sea-level rise to coastal zone management practices are performed through coastal vulnerability assessments. Out of the types of vulnerability assessments, a proposed model demonstrated that relative vulnerability of different coastal environments to sea-level rise may be quantified using basic information that includes coastal geomorphology, rate of sea-level rise, and past shoreline evolution for the National Assessment of Coastal Vulnerability to Sea-Level Rise for U.S. Coasts. The proposed methodology focuses on identifying those regions where the various effects of sea-level rise may be the greatest. However, the vulnerability cannot be directly equated with particular physical effects. Thus, using this concept as a starting point, a coastal vulnerability matrix and a coastal vulnerability index that use indicators of impacts of sea-level rise are developed. The developed model compares and ranks different regions according to their vulnerabilities while prioritizing particular impacts of sea-level rise of the region. In addition, the developed model determines most vulnerable parameters for adaptation measures within the integrated coastal zone management concept. Using available regional data, each parameter is assigned a vulnerability rank of very low to very high (1–5) within the developed coastal vulnerability matrix to calculate impact sub-indices and the overall vulnerability index. The developed methodology and Thieler and Hammar-Klose the proposed methodology were applied to the Göksu Delta, Turkey. It is seen that the Göksu Delta shows moderate to high vulnerability to sea-level rise. The outputs of the two models indicate that although both models assign similar levels of vulnerability for the overall region, which is in agreement with common literature, the results differ significantly when in various parts of the region is concerned. Overall, the proposed Thieler and Hammar-Klose method assigns higher vulnerability ranges than does the developed coastal vulnerability index sea-level rise (CVI-SLR) model. A histogram of physical parameters and human influence parameters enable decision makers to determine the controllable values using the developed model.
Keywords: Sea-level rise; Coastal vulnerability assessment; Geographic Information System; Coastal Zone Management.
Source: Özyurt, G., Ergin, A. (2010); “Improving coastal vulnerability assessments to sea-level rise: A new indicator-based methodology for decision makers”, Journal of Coastal Research: Vol. 26, No. 2, Pages 265-273; Received: 7 April 2008; Accepted: 15 September 2008; Published Online: March 2010, under DOI: 10.2112/08-1055.1.
Climate change associated with sea-level rise (SLR) is one of the major environmental concerns of today. This paper presents an assessment of the impacts of sea-level rise on the coastal zone of Kanyakumari District in Tamilnadu, India. Digital Elevation Model (DEM) combined with overlay techniques in GIS are used in determining the inundation zones along the coastal region. The analysis evaluated the impact on coastal fishing villages, landuse, tourist spots and sensitive areas under threat. The vulnerability of the coastal areas in Kanyakumari to inundation was quantified, based on the projected sea-level rise scenarios of 0.5 and 1 m. Our findings reveal that approximately 13 km2 of the land area of Kanyakumari would be permanently inundated due to SLR. This would result in loss of land, alteration of the coastal zone and affects coastal ecosystem. From the study, the mitigation measures (engineering measures) and Coastal Zone Management practices that can be taken to protect human life and property from sea-level rise are suggested.
Keywords: Sea-level rise; Digital Elevation Model; Kanyakumari; Tamilnadu; India; GIS.
Source: Natesan, U., Parthasarathy, A. (2010), “The potential impacts of sea-level rise along the coastal zone of Kanyakumari District in Tamilnadu, India”, Journal of Coastal Conservation; Received: 18 February 2010; Revised: 17 May 2010; Accepted: 19 May 2010; Published Online: 4 June 2010, under DOI: 10.1007/s11852-010-0103-6.
The Federal Emergency Management Agency (FEMA) recently completed a coastal demographics study of the United States and U.S. territories. As part of this study, FEMA estimated the United States population subject to the 1% annual chance (100 y) coastal flood hazard as mapped by FEMA. This determination followed a three-step process: (1) create a national digital flood hazard database by compiling the best available coastal-proximate, digital flood-hazard-area data using FEMA data sets; (2) develop a systematic method to separate coastal and riverine flood hazard areas and incorporate this boundary into the digital flood hazard database; and (3) combine the year 2000 census data with the digital flood hazard database using a geographic information system. This enabled estimates of the U.S. population subject to the 1% annual chance coastal flood. The analysis was conducted at the census block-group level, with census block-group populations (permanent residents) assumed to be uniformly distributed across each block group. The results demonstrate that approximately 3.0% of the U.S. population lives in areas subject to the 1% annual chance coastal flood hazard. It must be emphasized, however, that these numbers are based on the 1% annual chance (100 y) coastal flood. Historical coastal floods less frequent than the 1% chance annual flood have occurred in the U.S. on numerous occasions. If less-frequent coastal flood events were considered in this study, such as the 0.2% annual chance (500 y) coastal flood or, if seasonal (vacations) population were considered, then a much greater percentage of the U.S. population would be determined as subject to coastal flooding.
Source: Crowell, M., Coulton, K., Johnson, C., Westcott, J., Bellomo, D., Edelman, S., Hirsch E. (2010); “An estimate of the U.S. population living in 100-year coastal flood hazard areas“, Journal of Coastal Research: Vol. 26, No. 2, Pages 201-211; Received: 30 June, 2009; Accepted: 1 July, 2009; Available Online, under DOI: 10.2112/JCOASTRES-D-09-00076.1.