With climate changing, sea levels rising and the constant threat for tropical cyclones, densely populated South Florida is becoming increasingly vulnerable to storm surge flooding.
According to the Miami Herald, some 2.4 million people and 1.3 million homes are within four feet of the local high-tide line. Sea level rise is projected to more than double the risk of a storm surge at that level by the year 2030.
Rising Sea Levels Spell Trouble
A NASA report indicated that the global average sea level has risen a bit more than three inches since 1992 and could rise another three feet by the end of this century.
Climate Central conducted a two-year analysis on the threat across South Florida. They concluded the odds of a South Florida flood reaching more than four feet above high tide is over 15 percent by 2050.
More than half the population of Florida cities and towns lives below a four-foot line. Miami-Dade and Broward counties each have more people living less than four feet above high tide than any state except for Louisiana.
Back in 2013, High Water Line, an innovative art project that transforms scientific data to visual statements about rising sea levels, chalked a line around downtown Miami and Miami Beach indicating where the water would be with only a three-foot sea level rise.
On top of the general sea level rise, a direct hit by a major hurricane could be catastrophic as we move into the future.
According to a 2015 study by Karen Clark and Company, Miami was ranked No. 4 with estimated losses up to $80 billion from a 100-year (Category 5) hurricane.
Miami’s coastal features are actually a bit less prone to the highest storm surges as compared to cities like New Orleans or Tampa, but high property values near the coast make it more vulnerable to a high dollar value loss. Also, Miami has a higher probability of taking a direct hit from a Category 5 hurricane than other cities.
Using a web app called the Sea Level Rise Toolbox, residents and travelers alike can see the potential impacts climate change could have on the Miami area. The app was developed by professors and students at Florida International University’s School of Journalism and Mass Communications, using data collected by scientist Peter Harlem at FIU’s GIS Center.
Elevation data was provided by Google to complete the project, according to the journalism school’s sea-level rise website, Eyes on the Rise. Dr. Susan Jacobson, FIU School of Journalism professor, told weather.com in an email that the decision to omit specific years for the levels of sea-level rise were by design.
The bad news doesn’t stop at the surface, however. Because Miami is built on a foundation largely made up of limestone – which water passes through easily – building higher storm surge barriers won’t solve the problem of keeping out seawater, according to National Geographic.
The storm surge threat extends beyond Miami to sensitive ecological locations like Everglades National Park (elevation varies from zero to eight feet above sea level). This makes the area virtually unprotected from an onslaught of salt water intrusion into inland water systems.
Flooding Events Rapidly Increasing
The increased flood threat has begun to ramp up considerably over the past decade.
Since 2006, flooding in Miami Beach has spiked drastically, and a new study from the University of Miami used insurance claims, media reports and tidal gauges to determine just how extreme the flooding has become.
In the last decade, flooding has gone up 400 percent from high tides and 33 percent from rain, according to the study, published recently in the journal Ocean and Coastal Management. The high waters are blamed on a regional sea level rise that’s much higher than the global rate, a warning that waters can rise at different rates across the Earth.
“I was completely shocked when I found it was rising so fast,” University of Miami geophysicist and study lead author Shimon Wdowinski told the Miami Herald.
Tidal gauges in South Florida showed an increase in sea levels on pace with that of the rest of the world from 1998 to 2006, with levels jumping an average of .04 to .2 inches a year, the study found. However, in 2006, local levels underwent a dramatic spike, increasing by an average of .2 to .5 inches per year, much higher than global averages.
The heightened levels left widespread effects on flooding during high tides and the region’s wet season.
Business owners, developers and contractors have already been warned of the looming effects the rising sea levels could have on property value, making South Florida the epicenter for economic impact.
“All eyes are upon us and South Florida isn’t ready,” Wayne Pathman, a South Florida land use and environmental attorney, told the Real Deal, a South Florida real estate news site.
According to the Miami Herald, a whopping $152 billion worth of property will be under threat of flooding statewide by 2050, ranking first in a 2015 national survey.
If local sea rise rates are significantly higher than global averages, pumps, raised roads and other solutions for flooding will only provide protection for a shorter period of time than planned, researchers warn.
