These factors, combined with a unique set of regional geological characteristics, and high exposure to tropical cyclone storm surges, make south Florida a highly sea-level challenged part of the U.S. These conditions result in the largest tidal range seen over the course of a year. King tides occur when the Earth, Moon, and Sun are aligned at perigee (Moon is closest to the Earth) and perihelion (Earth is close to the Sun). King tides are a natural phenomenon determined by the predictable movements of the Earth, Moon, and Sun, but exacerbated by local weather patterns and regional ocean conditions. In addition, there are king tides, which occur seasonally, during the fall and early winter. Research has shown that in addition to eustatic sea level rise, there is a combination of other factors contributing to sea level rise along the southeastern coast of the U.S. are suffering from greater rates of sea level rise than most places. We learned in Module 4 that parts of the east coast of the U.S. Let’s consider some of the reasons behind the sunny day flooding and king tides that are disrupting the utopic life there. The porous nature of the limestone geology also precludes using methods like levees and dikes to hold back rising seas, as the water just migrates under any structures put in its way. This adds to the effects of “sunny day flooding” which Miami is becoming accustomed to. Furthermore, the design of the older drainage systems that rely on gravity flow to the ocean has resulted in sea water backing up onto roadways during high tides.

In addition, the geology presents other challenges: the oolite limestone platform is highly porous, so sea water can infiltrate beneath the ground and come up from below during high tides. You can explore the effects of sea level rise on Miami Beach at the NOAA Sea Level Rise Viewer, which allow you to search for a location and manipulate projected sea levels and visualize the effects on the chosen location. This is the area discussed in the video “ Is Miami Doomed?”. The lowest elevations are on the bay side of Miami Beach. In addition, the Florida peninsula is low in elevation and Miami beach has a maximum elevation of only a little over 1.5 m. The Florida peninsula is composed of a limestone platform and the barrier shoreline that Miami beach occupies sits upon this platform. The geology of this part of Florida makes it especially susceptible to sea level rise related issues. They may not be aware of the challenges associated with the rising seas coupled with the geography and geology of the area. Most people associate Miami Beach with glitzy wealth, beautiful Atlantic beaches, and a tropical climate. Part of the metro region, Miami Beach is a city of 91,700 people situated on a barrier island connected to the mainland and the city of Miami by bridges.

Miami oolite limestone