If it seemed like coastal flooding associated with king tides has been getting particularly worse in recent years, that is because it has, according to a new study by University of Florida scientists.

Essentially, a combination of weather factors and shifting atmospheric pressure pushed water up along the Atlantic coast south of Cape Hatteras, N.C., in what the authors call a sea-level rise hot spot.

King tides already cause regular incursions of seawater into many coastal communities, where continued (sea-level rise) is increasing the frequency of this so-called nuisance flooding, which may be further amplified by short-lived (sea-level rise) hot spots, the authors conclude in journal Geophysical Research Letters. We have demonstrated that (sea-level rise) hot spot anomalies are a recurring feature along the U.S. eastern seaboard related to the combined cumulative effects of (El Nio-Southern Oscillation) and (North Atlantic Oscillation) forcing.

The authors revealed they believe the cause of this sort of sea-level rise was similarly responsible for accelerated sea-level rise detected along the coast running from Massachusetts to North Carolina, something previously attributed to a slowing of a major Atlantic Ocean current.

This distinction is critical to the projection of (sea-level rise) along this heavily populated coastline and defines a new benchmark for ocean dynamic models to capture such a pattern of regional (sea-level rise) variability, the authors noted.

Meanwhile, a major federal climate change report receiving greater attention in recent weeks illustrates more clearly what researchers believe to be the factors driving long-term sea-level rise, along with other results from the effects of human behavior on the planet.

The last few years have also seen record-breaking, climate-related weather extremes, the three warmest years on record for the globe and continued decline in arctic sea ice, according to the Climate Science Special Report, a collaboration of 53 people across 13 agencies. These trends are expected to continue in the future over climate (multidecadal) timescales. Significant advances have also been made in our understanding of extreme weather events and how they relate to increasing global temperatures and associated climate changes.

Since 1980, the cost of extreme events for the United States has exceeded $1.1 trillion, therefore better understanding of the frequency and severity of these events in the context of a changing climate is warranted.

The report is part of the National Climate Assessment, something meant to take place every four years, but the NCA has only published three times in the 27 years since Congress passed the law creating it. And instructions on how to interpret the data into policy implementation will be a little more difficult, as Sunday the Trump administration disbanded the advisory committee tasked with that job.

Further, last week President Donald Trump signed an executive order reversing an Obama administration requirement that construction projects in coastal floodplains that receive federal dollars have to take into account sea-level rise and resulting flooding projections.

As predictions both get clearer and more dire from climate scientists, work is beginning to go into what might happen by the centurys end. Using a sea-level rise estimate of nearly six feet, Mathew Hauer leader of the University of Georgia Institute of Governments Applied Demography Program published a piece in the journal Nature Climate Change in April in which he estimates 13.1 million people in the United States could have to permanently move further inland.

Relationships between environmental stressors and migration are highly complex as press and pulse events trigger migration responses that range from short-distance temporary migration to permanent long-distance migration; some will move and others will not, Hauer wrote. (Sea-level rise) is unique among environmental stressors as the conversion of habitable land to uninhabitable water is expected to lead to widespread human migration without the deployment of costly protective infrastructure.

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New light cast on sea level, climate threats - Brunswick News