Fig 1.
Comparison of historical sea-level anomalies in San Francisco Bay (SFB) to global mean sea-level anomalies and projections.
The black dots represent the monthly mean sea level at the SFB tide gauge [31]. Note that the SFB tide gauge observations are not used in the global mean sea level modeling process. The green line represents synthesized global mean sea-level anomalies relative to the mean sea level in the year 2000 [32], where the gray envelope is the 90% credible interval and the blue line is the projected mean fitted to those anomalies.
Fig 2.
Storm surge analysis for San Francisco Bay area.
Shown are (panel a) the maximum recorded sea-level anomaly in a year, the annual block maxima, and (panel b) the return levels for the San Francisco Bay tide gauge (in meters).
Fig 3.
Estimated (panel a) probability density function of global mean sea-level rise in 2100 and (panel b) flood survival functions for San Francisco Bay.
In panel a, the dark red line represents the sea-level distribution in the year 2100, whereas, the orange and red points display the mean and Heberger et al. [7] (not accounting for land storage changes) sea-level estimate. In panel b, the baseline survival function for San Francisco Bay (yellow) is shifted relative to increases in global mean sea level by the mean sea-level projection (orange), the Heberger et al. [7] estimate (0.8 m; red), and each individual sea-level projection from the distribution of Markov chain Monte Carlo samples (gray) for the year 2100. Accounting for sea-level uncertainty produces the survival function in dark red. The associated return period is displayed on the right axis. The distance between the points on the dashed line (100-yr return period) to the same color point on the dark red curve display the flood risk underestimation.
Fig 4.
Hypsometric curve covering the elevations between -2 and 8 m in San Francisco County.
The gray area within the inset plot displays the area analyzed in this curve. The area in blue is water, whereas the area in tan is land. The dashed lines represent the elevation associated with the mean sea level (black), the baseline 100-yr storm surge (yellow), and the future 100-yr flood height (orange and dark red). The black curve displays the cumulative density or percentage of the area analyzed at elevations between -2–8 m. For example, ∼42% of the area analyzed has an elevation of 2.7 m (100-yr flood height accounting for uncertain sea-level rise) or lower.
Fig 5.
Sequential zoom in of the baseline and future 100-yr flood risk area in San Francisco.
The maps display the baseline 100-yr flood risk area in yellow. In the year 2100, the potential 100-yr flood height includes accounting for the mean sea-level projection (orange), the Heberger et al. [7] (not accounting for land storage changes) sea-level projection (red), and accounting for sea-level rise uncertainty (dark red). The star is the location of the tide gauge.
Table 1.
Comparison of flood risk area by the potential future 100-yr flood height accounting for different estimates of sea-level rise (SLR).