Sea level is projected to rise at least 16 inches along the California coast by 2050, with a 55-inch rise predicted by 2100. The primary impacts from sea level rise are increases in flooding and erosion. Sea level rise will expand the area vulnerable to flooding during major storms, as well as in the rare but catastrophic event of a major tsunami.
The term 100-year flood is used as a standard for planning, insurance, and environmental analysis. People, infrastructure, and property are already located in areas vulnerable to flooding from a 100-year event. Sea level rise will cause more frequent—and more damaging—floods to those already at risk and will increase the size of the coastal floodplain, placing new areas at risk to flooding.
Thousands of acres of former tidal wetlands currently at or below sea level around Humboldt Bay—including most of Manila, Samoa, Fairhaven, some residential and commercial areas of Eureka and Arcata, and many agricultural lands near the bay—are at risk of increased flooding in the coming years.
6/22/12
As the world continues to warm from climate change, most of California -- including San Francisco Bay -- will see a greater rise in sea level than other parts of the planet, according to a prominent national study released Friday.
The report, from the National Academy of Sciences, found that the impacts of melting ice and warming, expanding oceans will hit California harder because most of the state's coastline is slowly sinking due to geological forces.
Ocean levels south of Humboldt County will rise up to 1 foot in the next 20 years, 2 feet by 2050, and up to 5 feet by 2100, the study showed.
Aldaron Laird, who walked or kayaked all 102 miles of Humboldt Bay’s shoreline and its sloughs as part of his study, “Humboldt Bay Shoreline Inventory, Mapping and Sea Level Rise Assessment,” was the featured speaker on May 30 at the Arcata Marsh Interpretive Center.
Laird is an environmental planner who specializes in getting permits for wetland enhancement projects and doing historical studies of rivers and tidal waters. He produced the Humboldt Bay Historical Atlas in 2007.
This year, Laird is completing work for a California Coastal Conservancy grant to inventory the bay’s shoreline and “ground truth” GIS data on the shoreline’s attributes — part of a statewide effort to map areas that will be affected by sea level rise. During his tour of the bay's shoreline, Laird discovered that acres of diked farmland are currently ill-equipped to hold back the rising sea. The last native salt marsh ecosystems are also at risk of being drowned out by sea level rise. Laird’s presentation will include some of his 14,000 photographs taken during the project.
To watch online, click HERE. Thanks to Access Humboldt!
For more info, see "Aldaron's Walkabout" in January's North Coast Journal.
3/13/12
About 3.7 million Americans live within a few feet of high tide and risk being hit by more frequent coastal flooding in coming decades because of the sea level rise caused by global warming, according to new research.
If the pace of the rise accelerates as much as expected, researchers found, coastal flooding at levels that were once exceedingly rare could become an every-few-years occurrence by the middle of this century.
2/15/12
Rapid sea level rise in the next 100 years could affect more than coastal residents may think.
The rise could change the environment of the Arcata Marsh, create prime salmon habitat or affect property values, said local scientist Michael Furniss.
