as_uhslc_all_slr_xflood_8ft_50day_v3 Carla Baizeau Philip R. Thompson 20230926 3.0 This extreme high-tide flooding layer provides a prediction of future sea level rise (SLR) inundation and was produced using a passive flooding model, often referred to as a "bathtub" model. It provides an assessment of flooded areas according to a specific water level. As an alternative to the SLR scenarios in other data layers that we provide, our project also provides the ability to select specific amounts of SLR in increments of one foot, independent of any particular scenario. This information can be used if guidance for a project requires planning for a specific amount of SLR rather than a time horizon. The present layer models a sea level rise of 8 feet (244 cm). We apply this model to the 2022 National Geodetic Survey (NGS) lidar DEM for American Samoa with 1-meter resolution. The DEM was leveled from NAD83 (PA11) to mean higher high water at 0 m (MHHW=0) in 2005. The adjustment of the DEM may lead to inaccuracies due to the lack of historic information. It is also important to acknowledge that any inaccuracies in the DEM will lead to inaccuracies in the flooding estimates. When assessing the impacts of future sea level rise, it is important to consider how often flood conditions will occur in a given year. A low-lying location will begin to see impacts of being flooded a few times per year. Then, as sea level rise increases, it will flood tens of times per year. Eventually, that location may be flooded under a daily high tide. The present scenario models a frequency of 50 flooding days per year. Please note that this frequency represents an average number of times per year (Thompson et al., 2021). Any particular year may have substantially more or less flooding days depending on local climate variability (such as the El Nino, La Nina cycle) and year-to-year variability in the tides due to changes in the alignment of the Earth, Moon, and Sun. Secondly, flooding frequencies are based on data from the Pago Pago tide gauge on Tutuila, which means that estimates may not perfectly represent local conditions outside the harbor or on other islands. However, this is the best source of information available, and we do not expect this to lead to significant inaccuracies in the estimates of flooding frequency. In the 8-ft scenario represented here, the modeled water level for a 50-day frequency is 309 cm. Flood depth is provided in centimeters above the 2005 mean higher high water (MHHW) tide level. It is essential to emphasize that the passive flooding model used to produce this data layer does not include the effects of waves on flooding. As a result, the extent and impacts of future flooding under high-wave conditions are not represented, which should be accounted for in planning efforts. In addition, the DEM is assumed to be unchanged as sea level rises, but in fact there will be erosion and changes in the shape of the land surface, and continued subsidence. This also must be considered, and it is best practice to consider any flooding extent or depth represented in this data layer as a best-case scenario, with the effects of dynamic shoreline processes leading to greater flood extent and depth than presented. PacIOOS provides timely, reliable, and accurate ocean information to support a safe, clean, productive ocean and resilient coastal zone in the U.S. Pacific Islands region. -171.089797256602 -168.141348975554 -11.0480017523415 -14.5591355232811 http://pacioos.org/metadata/browse/as_uhslc_all_slr_xflood_8ft_50day_v3.png Sample image. PNG GCMD Science Keywords Earth Science > Climate Indicators > Atmospheric/Ocean Indicators > Sea Level Rise > Inundation Earth Science > Human Dimensions > Environmental Impacts Earth Science > Human Dimensions > Natural Hazards > Floods Earth Science > Oceans > Coastal Processes > Sea Level Rise GCMD Location Keywords Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Aunuu Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Manua Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Ofu Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Olosega Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Rose Atoll Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Swains Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Tau Ocean > Pacific Ocean > South Pacific Ocean > Polynesia > American Samoa > Tutuila None Use Limitation: This data layer provides a scientific prediction of potential future conditions from flooding due to sea level rise. The methodology is based on published, peer-reviewed techniques. However, as with any forecast, accuracy cannot be guaranteed and actual impacts may vary from these predictions. While considerable effort has been made to implement all components in a thorough, correct, and accurate manner, errors are still possible. The results are provided without warranty of any kind. The risks associated with use or non-use of the results are assumed by the user. The data may be used and redistributed for free but is not intended for legal use, since it may contain inaccuracies. Neither the data Contributor, University of Hawaii, PacIOOS, NOAA, State of Hawaii nor the United States Government, nor any of their employees or contractors, makes any warranty, express or implied, including warranties of merchantability and fitness for a particular purpose, or assumes any legal liability for the accuracy, completeness, or usefulness, of this information. University of Hawaii at Manoa Carla Baizeau physical and mailing

Unknown cbaizeau@hawaii.edu Using data produced by the University of Hawaii Sea Level Center (UHSLC), this product was developed in cooperation with the Pacific Islands Ocean Observing System (PacIOOS) at the University of Hawaii at Manoa (UH) School of Ocean and Earth Science and Technology (SOEST) and the Department of Oceanography at UH SOEST in partnership with the University of Hawaii Sea Grant College Program, also within UH SOEST. An associated online viewer was funded by the Pacific Islands Climate Adaptation Science Center (PI-CASC). Pacific Islands Ocean Observing System (PacIOOS) physical and mailing

Unknown info@pacioos.org Unknown Open Geospatial Consortium Web Feature Service (WFS) https://geo.pacioos.hawaii.edu/geoserver/PACIOOS/as_uhslc_all_slr_xflood_8ft_50day_v3/ows?service=WFS&version=1.0.0&request=GetCapabilities Open Geospatial Consortium Web Map Service (WMS) https://geo.pacioos.hawaii.edu/geoserver/PACIOOS/as_uhslc_all_slr_xflood_8ft_50day_v3/ows?service=WMS&version=1.3.0&request=GetCapabilities Open Geospatial Consortium Web Map Service - Cached (WMS-C) https://geo.pacioos.hawaii.edu/geoserver/PACIOOS/${id}/ows?service=WMS&version=1.1.1&request=GetCapabilities&tiled=true GeoServer This URL provides access to this dataset via GeoServer, which offers multiple output formats and an OpenLayers viewer. https://geo.pacioos.hawaii.edu/geoserver/ PacIOOS: American Samoa Sea Level Rise Viewer This URL provides a viewer and/or data access for this dataset. http://pacioos.org/shoreline/slr-amsam/ Related URL NOAA National Geodetic Survey (NGS). 2022. NOAA NGS Topobathy Lidar DEM of Ofu and Olosega, American Samoa. NOAA National Centers for Environmental Information (NCEI). https://www.fisheries.noaa.gov/inport/item/72129 Related URL NOAA National Geodetic Survey (NGS). 2022. NOAA NGS Topobathy Lidar DEM of Rose Atoll, American Samoa. NOAA National Centers for Environmental Information (NCEI). https://www.fisheries.noaa.gov/inport/item/72133 Related URL NOAA National Geodetic Survey (NGS). 2022. NOAA NGS Topobathy Lidar DEM of Swains Island, American Samoa. NOAA National Centers for Environmental Information (NCEI). https://www.fisheries.noaa.gov/inport/item/72139 Related URL NOAA National Geodetic Survey (NGS). 2022. NOAA NGS Topobathy Lidar DEM of Ta'u, American Samoa. NOAA National Centers for Environmental Information (NCEI). https://www.fisheries.noaa.gov/inport/item/72142 Related URL NOAA National Geodetic Survey (NGS). 2022. NOAA NGS Topobathy Lidar DEM of Tutuila, American Samoa. NOAA National Centers for Environmental Information (NCEI). https://www.fisheries.noaa.gov/inport/item/72145 None specified 20260601 Carla Baizeau University of Hawaii at Manoa mailing and physical Unknown cbaizeau@hawaii.edu Content Standard for Digital Geospatial Metadata: Extensions for Remote Sensing Metadata FGDC-STD-012-2002