Sinking land will exacerbate flooding from sea level rise in Bay AreaLeave a Comment
- Subsidence combined with sea level rise around San Francisco Bay could double flood-risk area
March 7, 2018 University of California – Berkeley
…A new study of subsidence around San Francisco Bay shows that for conservative estimates of sea level rise, twice the area is in danger of flooding by 2100 than previously thought. Some landfill is sinking 10 mm per year, threatening the airport and parts of Silicon Valley…
[Note: The USGS CoSMoS modeling that underlies the Our Coast Our Future tool (developed by Point Blue, USGS, and others) accounts for uncertainty in spatially variable vertical land motion for the SF Bay Region– see “Flood Potential” topic in section 1 in OCOF flood map. The vertical land motion component that went into understanding the uncertainty of the flood mapping for original SF Bay OCOF work (image below) was developed by the same author, Roland Burgmann, through the NOAA’s National Estuarine Research Reserve. This new paper is a refinement of these data.]
“We are only looking at a scenario where we raise the bathtub water a little bit higher and look where the water level would stand,” said senior author Roland Bürgmann, a UC Berkeley professor of earth and planetary science. “But what if we have a 100-year storm, or king tides or other scenarios of peak water-level change? We are providing an average; the actual area that would be flooded by peak rainfall and runoff and storm surges is much larger.”
…”Accurately measuring vertical land motion is an essential component for developing robust projections of flooding exposure for coastal communities worldwide,” said Patrick Barnard, a research geologist with the U.S. Geological Survey in Menlo Park [and OCOF PI]. “This work is an important step forward in providing coastal managers with increasingly more detailed information on the impacts of climate change, and therefore directly supports informed decision-making that can mitigate future impacts.”….