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<br /> <br /> <br /> <br /> <br />The matrix of numbers presented in Table 5 can be used to understand a range of total <br />water levels, from 0 to 95 inches above MHHW, represented both in terms of today’s tides <br />and future tides as sea level rises. Each total water level represents a combination of sea <br />level rise (0 to 60”) and tide levels (MHHW to a 100-year extreme event). As an example, <br />the likely mid-century daily high tide is projected to be 12” above today’s high tide, or <br />12”+MHHW. This water level is color coded in green in Table 5. This total water level is <br />approximately the level observed during King Tide, which is an astronomical tides that <br />occur approximately twice per year when the Moon and the Sun simultaneously exert their <br />gravitational influence on the Earth. <br /> <br />Because of the uncertainties associated with modeling and mapping sea level rise it is <br />reasonable to allow for a +/- 3-inch range when interpreting the total waters in Table 5. As <br />an example, the likely end-century high tide is projected to be 36 inches above today’s high <br />tide, or 36”+MHHW. Water levels ranging from 33 to 39 inches can be used to understand <br />what other combination of tides and sea level rise that may result in the same amount of <br />flooding or inundation as 36”+MHHW. <br /> <br />The values presented in Table 5 are generally applicable to central San Francisco Bay30 and <br />are therefore appropriate for local and regional scale climate adaptation planning, although <br />it may not be as precise for some areas of south and north Bay. In addition, because tide <br />levels do vary around the Bay, additional information about tide levels should be used for <br />site-scale planning. Finally, the values in Table 5 are based on an analysis that does not <br />include the effects of locally wind waves and assumes that future storms will behave like <br />past storms. <br /> <br /> <br />30 Existing condition water levels in the first row of Table 5 are based on FEMA model results for Central San <br />Francisco Bay, http://www.r9map.org/Pages/San-Francisco-Coastal-Bay-Study.aspx, and are being used by <br />Alameda and San Francisco Counties. Existing water level conditions for the other counties in the Bay Area will be <br />available by the end of 2015.