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These hazard zones depict flooding caused by a coastal storm. The processes considered include (1) storm surge (a rise in the ocean water level caused by waves and pressure changes during a storm), (2) wave overtopping (waves running up over the beach and flowing into low-lying areas, calculated using the maximum historical wave conditions), (3) extreme lagoon water levels which can occur when lagoon mouths are closed and fill up during rainfall events, and (4) additional flooding caused by rising sea level in the future. This hazard zone also takes into account areas that are projected to erode in the future, sometimes leading to additional flooding through new hydraulic connections between the ocean and low-lying areas. These hazard zones do NOT consider upland fluvial (river) flooding and local rain/run-off drainage, which likely play a large part in coastal flooding, especially around coastal confluences where the creeks meet the ocean. There are two types of inundation areas: (1) areas that are clearly connected over the existing digital elevation through low topography, (2) and other low-lying areas that don’t have an apparent connection, as indicated by the digital elevation model, but are low-lying and flood prone from groundwater levels and any connections (culverts, underpasses) that are not captured by the digital elevation model. This difference is captured in the “Connection” attribute (either “connected to ocean over topography” or “connectivity uncertain”) in each rising tides dataset. We recommend these be mapped as separate colors. CCWG merged the coastal hazard layers to create a new combined hazard layer for each planning horizon (Existing, 2030, 2060 and 2100). These merged layers represent the combined vulnerability zone for “Coastal Climate Change” for each time horizon. Projections of the combined hazards of Coastal Climate Change are intended to help estimate the cumulative effects on the community and help identify areas where revised building guidelines or other adaptation strategies may be appropriate. Combined hazards however, do not provide municipal staff with the necessary information to select specific structural adaptation responses. Therefore, this study also evaluates the risks associated with each individual coastal hazard.When compiling hazard data layers for the combined threatened area within each time horizon, classifications of the ‘vulnerable,’ ‘managed,’ and ‘protected’ areas described in the previous section, were chained to the coastal flooding attributes.-------------------------------This feature is one in a series of coastal flood and erosion hazard zones developed as part of the Monterey Bay Sea Level Rise Vulnerability Study. For detailed documentation about how these hazard zones were developed, please see "Monterey Bay Sea Level Rise Vulnerability Assessment: Technical Methods Report," a report prepared by ESA PWA for The Monterey Bay Sanctuary Foundation in March 2014.-------------------------------The name of this shapefile reflects the future scenarios and planning horizon that the hazard zone represents, as follows:"coastal_floodhz" + _ + sea level rise scenario + planning horizon-------------------------------Sea level rise scenarios:ec – Existing conditions (2010 water level)s1 – Low sea level rise (41 cm by 2100)s2 – Medium sea level rise (88 cm by 2100)s3 – High sea level rise (159 cm by 2100)-------------------------------Planning horizons:2010 (Existing conditions)203020602100--------------------------------Armoring:filenames ending in "a" include existing coastal armorning in the analysis |