The rising water level is mostly due to a combination of meltwater from glaciers and ice sheets and thermal expansion of seawater as it warms. In 2019, global mean sea level was 3.4 inches (87.6 millimeters) above the 1993 average—the highest annual average in the satellite record (1993-present).

Approximately a fifth of the population lives in low-lying coastal urban centers — comprised of densely clustered residents, buildings, and infrastructure — less than 10 meters above sea level. These areas are especially vulnerable to flooding and storm surge impacts.

As global sea level rises, the action of waves at higher elevations increases the likelihood for extensive coastal erosion. Already, coastal erosion costs roughly $500 million per year for coastal property loss, including damage to structures and loss of land.

Rising sea levels, combined with reductions in freshwater runoff due to drought, will cause the salt water-freshwater boundary to move further upstream in tidal estuaries. Upstream shifts of this boundary can reduce the water quality of surface water resources.

Global sea level is rising approximately 0.13 inches (3.3 millimeters) a year. That’s 30% more than when NASA launched its first satellite mission to measure ocean heights in 1992.

What’s Going On: According to the New York Times, between 24% and 37% of the country is underwater. According to official government data, 4.7 million people have been displaced, 984,819 houses have been inundated, and 129 people have died.

Florida’s high point is 345 feet above sea level, the lowest of all fifty states. Thus it will never go completely underwater, even if all the ice sheets and glaciers on the planet melt, since a total meltdown of all the ice sheets glaciers would raise sea level 212 feet (65 meters).

At any rate, it could even be as early as 2050 when much of the Florida coastline would be underwater, depending on what the results of newer data might say. Flooding would affect Miami, Orlando, Tampa Bay and any other major center touching saltwater.

Two thirds

Lakewood

Challenger Deep

Guadalupe Peak

Texas is bordered by New Mexico in the northwest; Oklahoma in the north and northeast; Arkansas, Louisiana, and the Gulf of Mexico in the east; and Mexico in the southwest.

Trans-Pecos region