<meta http-equiv="refresh" content="0; url=https://r.sealevelrise.org/https://sealevelrise.org/states/alabama/"/> Alabama's Sea Level Rise - Sea Level Rise

Overview

Alabama’s Sea Level Has Risen Over 11” Since 1966

And It’s Costing Over $24 Million

The sea level around Alabama is 11 inches higher than it was in 1966.1 This increase is mostly due to Alabama’s sinking land, and it’s causing major issues. The shorelines of the state’s barrier islands are receding by as much as 12 feet per year and important habitats are disappearing.2 As the sea level rises, it makes existing coastal flooding more severe and it erodes beaches, eventually submerging both wetlands and dry land. On Dauphin Island, over 50 years of land erosion has already caused the island’s mass to decrease by 16%, with a total of 350 feet of the beach destroyed to date.2 There are already over 7,000 properties at risk from frequent tidal flooding in Alabama.3 The state is planning over $24 million in sea level rise solutions, which include shoreline restoration and protection, stormwater mapping, and seawall repair.

Sea level rise is speeding up

Although the sea has only risen by 11 inches since 1966, its speed of rise has accelerated over the last ten years and it’s now rising by over 1 inch every 2 years.1 We know this because the sea level is measured every 6 minutes.4 Scientists use different equipment like satellites, floating buoys off the coast, and tidal gauges to accurately measure the local sea level as it accelerates and changes.

Created with Highcharts 6.2.0

SEA LEVEL MEASUREMENT FROM DAUPHIN ISLAND AREA TIDE GAUGE SINCE 1950

Causes & Complications

Why Are Sea Levels Rising?

While there are four causes of sea level rise in Alabama, land sinkage is the main contributor.5 The ground is sinking slightly each year, due to a natural process called subsidence. Rising sea level submerges land and erodes beaches making the streets and buildings that much lower to the sea. Click here to learn more about sea level rise.

How Land Sinkage Increases Sea Level Rise

Most flooding happens during the fall

King tides are unusually high tides that are created during months when the sun, moon, and earth align. The combined gravitational pull of the moon and the sun creates much higher tides, called king tides. In some places, king tides are brought on by changes in the weather and ocean patterns. In places like Alabama, king tides are typically over a foot higher than normal.1 Add that to the 11 inches of sea level rise since 1966, and you end up with flooding even on sunny days.

Solutions aren’t simple

In Alabama the sea level is rising more rapidly than most coastal areas because as the ocean water is rising, the land is sinking. In addition, the shorelines of barrier islands are receding by as much as 12 feet per year.2 With the rapid recession of lands, solutions to sea level rise are urgent but also complicated.

Forecast

What's the Future of Sea Level Rise?

In the last decade, the speed at which Alabama’s sea level is rising has increased and is now rising by over an inch every 2 years.1 Around Dauphin Island, it took the sea level 22 years to rise by 6 inches.1 Scientists forecast that in just the next 15 years, the sea level will have risen by another 6 inches.6

Scientists are not certain how fast the ocean will warm and ice will melt. They expect water levels to continue to rise faster, but are not sure just how fast. Therefore scientists from the National Oceanic and Atmospheric Administration (NOAA) and the US Army Corps of Engineers (USACE) have made predictions based on ranges from low to high.

Below you can see the range of the NOAA and USACE high and intermediate forecasts for various locations around Alabama.7 We are currently closest to the USACE high forecast, which is the darkest red line.

SLR speeding up - Alabama English
SLR speeding up - Alabama English
Created with Highcharts 6.2.0Dauphin Island Sea Level Rise Forecasts

Flooding

Why Are Floods More Frequent?

When the ocean rises high enough, high tides cause flooding even on sunny days. Even though the sea level has only risen by around 4 and a half inches, tidal flooding has increased by over 200% in Alabama since 2000.8

Flooding
How sea level rise affects Alabama

Flooding even when there’s no rain

Drainage systems are designed to channel excess rainwater from the streets and drain it into the sea. But with the pressure from rising sea levels and higher tides, seawater can get pushed into these pipes and spill out into the streets. This causes flooding even on days without rain.

Drain A
Drainage Under Normal Tidal Conditions
Drainage With King Tide / Sea Level Rise

Increased storm surge flooding

Unfortunately, slightly higher sea levels make hurricanes even more damaging. Just a few more inches of sea level rise allow a hurricane to push more water onto the land, even if the hurricane itself doesn’t make landfall.

Hurricane Ivan, 2004

Higher sea levels create a higher launching point for storm surge. These small changes in sea level rise are enough to turn what were 100-year storm surges into much more frequent events. In fact, in a third of 55 coastal sites studied throughout the US, 100-year storm surges will be 10-year or more frequent events by 2050.9

This means that in many coastal cities, if you bought a house with a 30-year mortgage today, by the time you paid off your mortgage you could be experiencing extreme 100-year storm surges ten times more frequently due to sea level rise alone. This does not include the added risk of more intense storms resulting from warmer water and a warmer atmosphere, which could further increase storm surge damage.

In 2004, Hurricane Ivan made landfall on the Gulf Coast of Alabama as a Category 3 Hurricane and caused $27 billion in damages.10 Without sea level rise, Hurricane Ivan’s 8.8 foot storm surge would have been lower.11

Hurricane Ivan, 2004

Costs

What's at Risk in Alabama?

There’s a lot at risk from sea level rise and flooding in Alabama, especially because the state is is experiencing a higher rate of sea level rise than most, due to land sinkage. Sea level rise along the Alabama coast is making existing coastal flooding more severe, eroding beaches, and will eventually submerge both wetlands and dry land. On Dauphin Island, land erosion from 1958 to 2007 has already caused the island’s mass to decrease by 16%, with a total of 350 feet of the beach destroyed to date.2 Barrier islands are important habitats for wildlife and protect against hurricanes.

Beaches
Beaches

Rising seas increase the speed of beach erosion, pulling more sand from the beach into sea. Replacing the sand is possible, but expensive.

Coastal Wetlands
Coastal Wetlands

Sea level rise can disrupt coastal wetlands, which puts important ecosystems in danger, threatens habitats, and leaves communities exposed to dangerous storm surge.

Homes & Cars
Homes & Cars

Storm surges or flooding can damage the underside of your car or the first level of your home.

In Gulf Shores there are 431 residential properties already at risk from repeated tidal flooding, by 2033 that number will increase to 681 as sea levels rise. In Orange Beach, 308 properties at risk will turn into 638 within 15 years. Mobile has 338 properties at risk, which will become 478. And in Bon Secour, there are 105 properties at risk, which will increase to 123 by 2033. Click here to explore other coastal areas in Alabama that are at risk at FloodiQ.com.

Alabama is spending over $24 million

Some cities have sufficient resources to deal with this problem while others do not. Alabama will need solutions at the individual, local, state, and federal levels to protect its coastal communities.

Mobile Bay
Mobile Bay

Mobile Bay is working on a $12.7 million project12 focused on the protection and restoration of vulnerable shorelines and a $3 million project for stormwater mapping.13

Alabama Point
Alabama Point

Alabama Point has allocated nearly $2.5 million for seawall repair.13

City of Gulf Shores
City of Gulf Shores

The city of Gulf Shores has nearly $6 million allocated for the Little Lagoon Restoration project.13

What can you do?

Individuals, mayors, legislators, governors, and Congress can work together to build protections before flooding, to build back stronger after flooding, and to create plans that future-proof our communities. Click here to see what solutions can help protect your home or what your community can do.