The nation’s shores are in trouble. After a year of record coastal flooding, a new report released by the National Oceanic and Atmospheric Administration found that it will be more frequent, more intense and more intense. most widespread in the US
High tide floods, also known as “royal tides” or “sunny day” floods, have already increased in frequency over the years as sea levels continue to rise. According to NOAA, it typically occurs when tides rise about 2 feet above the daily average and ocean water begins cascading over streets and bubbling up in storm drains.
This type of flooding used to really only happen during storms. But now, NOAA says it can happen only from a full moon or a change in prevailing winds or currents. Decades of sea level rise is to blame and the situation has only been driven by climate change.
“The East and Gulf coasts are already experiencing twice as many days of high tide flooding compared to 2000,” said Nicole LeBoeuf, director of NOAA’s National Ocean Service. said“flooding coastlines, streets and basements and damaging critical infrastructure.”
NOAA Tides and Currents
Some communities are already feeling the toll of the growing situation.
Reedy Point, Delaware, has already experienced six days of high tide flooding since January, one more day than it saw in 2021. Springmaid Pier, South Carolina, tied its 2021 record with 11 days of flooding . Kwajalein Island in the Pacific Marshall Islands also exceeded its 2021 high tide flooding.
Scientists say La Niña is what kept coastal areas from experiencing a record number of floods in 2022. But overall, conditions are only accelerating.
NOAA last reportreleased Tuesday, highlighted the agency’s “increased confidence” that the nation will hear the wrath of sea level rise sooner rather than later Over the next 30 years, the agency said, relative sea level along the contiguous U.S. coast is expected to rise, on average, by nearly 2 inches, the same amount as it rose over the past 100 years .
NOAA Tides and Currents
By 2050, just 28 years from now, NOAA predicts that “high tide flooding on a national scale” will last between 45 and 70 days. And it’s not just the number of floods that worries scientists, it’s also the intensity. In the next three decades, experts say major and moderate floods will occur as frequently as moderate and minor floods occur today.
Major coastal high tide floods, which are often destructive, will decrease from 0.04 events per year in 2020 to 0.2 events in 2050, a 400% increase.
NOAA Tides and Currents
Without action to reduce the impact, NOAA says in the report, the nation “will face significant consequences” ranging from damaged communities and overloaded stormwater and wastewater systems to stressed coastal ecosystems. Along with implementing resilience strategies in coastal areas, NOAA said overall global warming must be slowed by prevent the worst outcomes.
If the world reaches 2C of global warming compared to pre-industrial levels, oceans are expected to rise more than 1.5 feet globally and more than 2 feet around the contiguous US. Currently, NOAA says, the probability of this happening in 2100 is about 50. %. More greenhouse gas emissions, which fuel global warming, only increase that likelihood.
“Sea level rise is strongly affected by future global warming,” the report says. “By reducing greenhouse gas (GHG) emissions, we are more likely to avoid severe and transformative impacts later this century or early next along the coasts of the United States. A as greenhouse gas emissions and global temperatures continue to rise, the likelihood that U.S. sea levels will be very high. Rise does, too.”
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