Rising Sea Levels Could Double Extreme Flooding Events on Coastline, Report States

April 16, 2020 by Don Jergler

“Sea-level rise will radically redefine the coastline of the 21st century.”

That’s from a new study that shows rising sea levels could lead to extreme flooding events in some U.S. coastal areas doubling every five years.

The study published on Thursday in Scientific Reports suggests that extreme water levels that are now reached once every 50 years may be exceeded daily along U.S. coastlines before the end of the 21st century.

“We find that the odds of exceeding critical water-level thresholds increases exponentially with sea-level rise, meaning that fixed amounts of sea-level rise of only 1–10 cm in areas with a narrow range of present-day extreme water levels can double the odds of flooding,” the report states. “Combining these growth rates with established sea-level rise projections, we find that the odds of extreme flooding double approximately every five years into the future.”

Scientists from the U.S. Geological Survey, the University of Hawaii and the University of Illinois looked at the continuous shift in coastal flooding scenarios using tide gauges combined with data from sea-level rise scenarios to model the rate at which flooding events may increase in the future.

The report also shows that the present-day 50-year extreme water level will be exceeded annually before 2050 for 70% of the nation’s coastal regions, and the present-day 50-year extreme water level will be exceeded almost every day during peak tide before the end of the 21st century for 90% of the U.S. coast.

The report states that “long-term trend in mean sea level has profound consequences on the nature of extreme events,” and that sea-level rise will likely increase the odds of flooding by a thousand-fold in a half-century.

“With increased flood frequency, we expect a corresponding acceleration of a number of related coastal hazards, such as beach and cliff erosion,” the paper states. “Our society has yet to fully comprehend the imminence of the projected regime shifts in coastal hazards and the consequences thereof.”

Virginia

Virginia’s goal of being carbon free in the next 25 years gives it a singular distinction among Southern states.

Gov. Ralph Northam last week authorized the Virginia Clean Economy Act, which mandates that the state’s biggest utility, Dominion Energy, switch to renewable energy by 2045, while Appalachian Power, serving southwest Virginia, must go carbon-free by 2050 under the act. Nearly all the state’s coal plants must shut down by the end of 2024 under the new law.

“Virginia is the first state in the old Confederacy to embrace such clean-energy targets,” an article this week in the Washington Post states.

State Sen. Jennifer L. McClellan, D-Richmond, a sponsor of the bill, told the newspaper it “will create thousands of clean energy jobs, make major progress on fighting climate change, and break Virginia’s reliance on fossil fuels.”

The Virginia Clean Economy Act was passed as House Bill 1526 and Senate Bill 851 and incorporates clean energy directions in an executive order from the governor in September 2019.

It’s the result of “extensive stakeholder input,” while it incorporates environmental justice concepts related to the Green New Deal, according to Northam’s office.

The law requires new measures to promote energy efficiency, while setting a schedule for closing old fossil fuel power plants, and requiring electricity to come from 100% renewable sources such as solar or wind.

Energy companies will be required to pay penalties for not meeting their targets.

The Act accomplishes the following broad goals:

Establishes renewable portfolio standards.
Establishes energy efficiency standards, and sets an energy efficiency resource standard, requiring third-party review of whether energy companies meet savings goals.
Advances offshore wind. The act provides that 5,200 megawatts of offshore wind generation is “in the public interest.”
Advances solar and distributed generation. The act establishes that 16,100 megawatts of solar and onshore wind is “in the public interest,” and requires Virginia’s largest energy companies to construct or acquire more than 3,100 megawatts of energy storage capacity.

Swiss Re

A new report from Swiss Re Global shows warming will lead to growing intensity and frequency of severe weather events, rising losses, and greater uncertainty in the assessment of these events by the insurance industry.

And all off that could make some weather risks uninsurable.

“Failure to take immediate, tangible action to confront warming temperatures could lead to climate systems reaching irreversible tipping points,” stated the sigma report titled “Natural catastrophes in times of economic accumulation and climate change.”

The report, detailed in a recent article by Insurance Journal’s Lisa Howard, forecasts that economic and insured losses resulting from such events will rise in the coming decades.

The report emphasized the insurability of weather risks could be jeopardized, particularly in high-exposure accumulation areas.

“We believe weather-related risks remain insurable. However, to improve risk assessment and ensure insurability in the face of many uncertainties, insurers need to continually adapt their models to changing parameters,” said Swiss Re in the report.

The Swiss Re report further suggested that the modeling and underwriting communities must develop better methods and the industry needs to be able to better understand how factors such as GDP growth and urbanization, which are not fully captured in risk models, can affect rising risks and losses.

More sophisticated modeling approaches are also needed to account for the growing loss impacts of secondary perils, which have been inadequately modeled in the past. Secondary perils are the smaller to mid-sized events, or secondary effects, that follow a primary peril, such as a storm surge or flooding after a hurricane.

COVID-19 and Climate Change

The ongoing worldwide pandemic may be laying the groundwork for a unified battle against climate change, the World Economic Forum says.

In a blog “How COVID-19 might help us win the fight against climate change,” the group acknowledges the human costs of the pandemic are “horrifying,” but finds hope in the response, which it notes has been characterized by “care, compassion and connection – and an unheard-of pace of change.”

It postulates the world could seize this moment as a of opportunity to rebuild society and the economy in a better way.

“With scientists warning we have 10 years left to avoid the worst consequences of climate change, this could offer an opportunity to fix the climate crisis before it’s too late,” the blog states.

It lists five actions to lay this groundwork:

Re-think risk: If the pandemic teaches us to acknowledge our vulnerability to high-impact shocks such as pandemics and climate-related disasters, we will be infinitely better placed to prepare for them.

Listen to global perspectives: The jury is out on whether COVID-19 will prompt the world to choose the route of national isolation or global solidarity, but a growing understanding that we are inherently connected can help build momentum for strong climate action.

Make people the top priority: Many individuals are re-arranging their lives to practice social distancing, offering elderly neighbors help with their chores and volunteering in health facilities and food banks, showing the power that can be unleashed when we are united behind a common cause.

Trust experts: The advice of epidemiologists has gone viral (we’ve all seen the “flatten the curve” meme). This might represent a turning point in a trend towards the demise of experts. We need to listen to climate scientists and policy advisors to win the climate change fight too.

Make a cultural shift: Much remains uncertain about what the world will look like when we emerge from the COVID-19 pandemic, but the fundamental societal changes we are witnessing may well offer us a final chance to avoid a climate catastrophe.

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