The Humboldt Bay area is experiencing the fastest rate of relative sea level rise on the West Coast. That's because tectonic activity is causing the ground beneath the bay is sinking at the same rate the ocean is rising. According to the California Ocean Protection Council's 2018 projections, sea level in the Humboldt Bay area is expected to rise above 2000 sea level as much as 1 foot by 2030, 2 feet by 2050, and 3 feet by 2060. In late 2021, scientists reported that Antarctica's Thwaites Glacier is likely to collapse within 5 to 10 years, which could result in an additional 2 to 10.8 feet in sea level rise. 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. But these extreme storms are happening with increasing frequency, in part due to rising seas. 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.To view sea level rise scenarios for the Humboldt Bay area, visit NOAA's 2022 Sea Level Rise Viewer and go to the local scenario for the North Spit.
New York City is vulnerable to rising seas and larger, more powerful storms that result in more frequent and intense flooding and what was once a 500-year flood prior to human-induced climate change now occurs on average once every 24 years. This is according to a study published in the Proceedings of the National Academy of Sciences.“Flood heights are increasing and have increased since the pre-anthropogenic era, not only because of rising sea levels but also because of the impact that climate change is having on tropical cyclones,” said lead author Andra Reed of Penn State University.Reed and colleagues made their conclusions based on climate models that simulated tropical storms and subsequent flooding for the region beginning in 850. They found that average flood height increased by more than 4 feet from 850 to 2005.When Hurricane Sandy hit New York in 2012, it caused an estimated $50 billion in damage and destroyed at least 650,000 houses. Prior to 1800, such a flood could be expected to hit the city every 3,000 years. Today, a flood of that magnitude will occur on average every 130 years, Reed said. “Our planning is not designed to look forward,” said Melanie Gall, a University of South Carolina professor who studies disaster risk and emergency management. “When you look at flood insurance or how flood zones are mapped, it is always based on past events. It never looks at how storm surge will change in the future. There needs to be more proactive planning.”Continuing development in New York and other coastal areas is also making the impact of such floods worse, similar to how water in a bathtub rises when displaced by a person entering the tub.“The area that will be affected is larger because there is more development,” Gall said.Read More
Forty-four feet isn't all that high. It's halfway up the tall side of the county courthouse. If you stacked Guy Fieri seven-and-a-half times on top of himself, his platinum blond hair would reach 44 feet high. Forty-four feet is also the height above today's sea level where 37 tons of radioactive waste from the former PG&E Humboldt Bay power plant is entombed in a concrete vault at the edge of the bay. A new coalition called, you guessed it, 44 Feet has brought together state agencies, federal and local political interests, scientists, a few folks with no titles at all and, to some extent, the nuclear plant's owner, PG&E. Like nanoplastics and deep-fried butter, most of us do not want to think about radioactive waste stored nearby, but 44 Feet is trying to plan for its future safety, even if that future is 100,000 years away.PG&E's old nuclear power plant sat next to U.S. Highway 101 at King Salmon. It ran a brief and ignominiously leaky life from 1963 to 1976. Still, it produced high-level radioactive waste from the uranium fuel it used to create electricity. The radioactivity has cooled somewhat in the intervening years, but it will remain hot and toxic for more than 100,000 years.Read More
Three feet of sea-level rise would have significant impacts to communities surrounding Humboldt Bay, but that’s exactly what’s expected to happen in the coming decades.That’s why the Humboldt County Civil Grand Jury’s second report “The Sea Also Rises,” issued Thursday, states that Humboldt County, the cities of Arcata and Eureka, the Humboldt Bay Harbor, Recreation and Conservation District, and state legislators need to start collaborating on planning for sea-level rise.“A regional voice speaks louder than multiple local voices,” the report states.Some of those efforts are at the beginning stages. Humboldt County’s Planning and Building Department, for instance, is expected to conclude the Humboldt Bay Sea Level Rise Regional Planning Feasibility Study in September 2022 and that will likely recommend taking a collaborative approach to the issue.Read More
The Humboldt County Grand Jury's report is an excellent overview of how sea level rise will impact the Humboldt Bay Area. In plain language that's easy to understand, the report discusses the current understanding of the problems our region will face in the coming decades. It also identifies obstacles to "adaptation planning," or how we will adapt to lessen the impacts on people, highways, sewer plants and pipelines, electrical transmission and water lines, low-lying contaminated sites, etc. We need to start planning now so we can take action before these situations become emergencies, putting public health, safety, and the environment at risk. Below are some excerpts: Most people think of SLR as a problem when barriers get overtopped. They often overlook inundation that occurs when water seeps through the barriers. Few realize that even with well-maintained barriers, sea water will permeate through the barriers and intrude into the ground water on the other side. This process is known as salt water intrusion and must be considered when protecting our threatened areas. The Grand Jury believes SLR planning needs to be a priority among all elected officials in the County. The County of Humboldt; the cities of Arcata and Eureka; and the Humboldt Bay Harbor, Recreation, and Conservation District should formally state their immediate and continuous support for, and commitment to, SLR mitigation and adaptation efforts. Read More
Scientists, speaking at the American Geophysical Union Fall Meeting in New Orleans this month, reported that a critical section of the keystone Antarctic glacier, Thwaites Glacier, will likely collapse in the next five to ten years. The research, led by Erin Pettit of Oregon State University, predicts that the Thwaites ice shelf will break apart within the next decade because of startling increases in surface fractures and rifts.Thwaites Glacier is one the largest Antarctic glaciers, comparable to the size of Great Britain or Florida. Meltwater from Thwaites alone is responsible for 4% of global sea level rise, leading it to receive a great deal of scientific attention in recent years.The nickname ‘Antarctica’s doomsday glacier’ is given to Thwaites because if the ice shelf collapses, the glacier and the enormous volumes of ice upstream that funnel into the glacier will no longer be restrained from accelerating into the ocean. “It is the potential long-term effect on the rest of the grounded ice sheet that we need to consider,” explains Anne Le Brocq, a senior lecturer in physical geography at the University of Exeter. If the entire glacier were to melt then global sea levels would rise by 65 centimeters, or about two feet. If Thwaites Glacier, and other critical neighboring glaciers such as Pine Island Glacier, cannot hold back the West Antarctic Ice Sheet, which holds the equivalent of 3.3 meters (10.8 feet) in sea level, then it could affect coastlines across the world.Read More