The Shoreline of the Future: Permanently Temporary

Sea level was much higher, 600 feet, millions of years ago. During the last ice age, around 20,000 years ago, sea level was almost 400 feet lower than it is now. Since then, there has been a considerable rise in sea level in the world. The reason behind it is not natural circumstances but human actions. But what does The Shoreline of the Future hold? Are we ready to adapt to this Permanently Temporary living with rising seas?

What Is the Meaning of Shoreline Change?

It refers to the gain or loss of a particular land area and/or change to the landscapes on the shoreline or marine edge. It is considered as an important indicator for environmental threats on coastal areas. The shoreline is a narrow, linear area always in contact with the waterbody. It serves as a boundary between land and the estuary or sea, and is defined in terms of time and space.

It is dangerous because shoreline changes affect natural habitats and are capable of destroy cultural resources, facilities along with other infrastructure.

Factors Affecting Location of a Shoreline

While global sea level changes are influenced by various factors such as the growth and melting of continental glaciers and large-scale changes in continental margins and ocean floors, there are also regional processes that cause relative sea level to rise or fall, affecting specific coastlines while leaving others unaffected.

The position and height of the sea or lake compared to the land, known as relative sea level, decides where shorelines are located.

Changes in the amount of melted water.
Circulation patterns
Coastal uplift or subsidence caused by tectonic processes like earthquakes and volcanoes.
Compaction and deposition of sediments
Crustal rebound caused by glaciation
Fluctuations in the angular velocity of Earth or polar drift can also lead to variations in relative sea level.
Sea level fluctuations
Sediment supply
Thermal expansion of ocean waters
Tides and waves
Withdrawal of fluid.

Permanently Temporary Living with Rising Seas

Throughout history, mankind has never confronted the concept of sea level fluctuations or the consequential shifting of the shoreline further inland if left unaddressed. But now, we have a different opinion about this.

In the coming years, the whereabouts of the shoreline will consistently remain in a state of “permanently temporary.” This abstract notion can be quite challenging to comprehend. To address this challenge, we need to find new ways to plan, develop, and make use of our shoreline areas. We must consider the fact that the shoreline will continue to move inland and adapt accordingly.

To cope up there are different actions under consideration:
To build new architectural forms that are capable of adapting to rising sea levels.
Floating structures are also thought about in some places.
Mobile structures that are easy to disassemble, move, and reassemble are also in the list.
At some places, they are thinking of designing buildings with time boundations. Particularly, they would last only for a couple of years.

Regrettably, certain laws and regulations currently in effect were established under the assumption that the shoreline would remain fixed. This has created significant challenges, if not insurmountable obstacles, when it comes to approving resilient structures capable of withstanding the impacts of rising sea levels. Once we have determined the characteristics of a resilient shoreline development, it will be necessary to restructure our laws in order to enable government agencies to grant permits for these resilient structures.

The current onshore movement of sediment is primarily due to the rise in sea level following the glacial period. The sediments on the continental shelves that were once exposed are still moving towards the land due to the rising sea levels during the Holocene period. This movement is happening because of the adjustment of the nearshore zone to today’s tidal and wave conditions.

Global sea level rise will greatly affect coastal parks along with the following issues: Flooding

Convert saltwater intrusions into aquifers resulting in salinization of groundwater
Create or destroy wetlands and marshes.
Land loss or gain
Wash away coastal sediments.
Waterlogged soil

With increased salt stress on flora, there would possibly be a decline in prairie areas, mangroves, and marshes. Moreover, a relative rise in sea level may largely affect coastal processes, structures, communities, sandy beaches.

Each natural sea level cycle lasted for about 100,000 years and when global temperatures were lowest, a huge portion of water supply was frozen into ice sheets. At that time, the sea level was at its lowest. Unfortunately, with a rise in temperature, those ice sheets started melting considerably, increasing the ocean and sea levels. For every 100,000-year cycle, the cooling period was about 80,000 years long whereas the warming season lasted for about 20,000 years.

With increased stress on environment with each passing year and ever-increasing pollution and CO2 emission, we are unable to control temperature rise. So, instead of getting cooler, both atmospheric and oceanic temperature increased about 1.5° Celsius. Yes, despite we are in the cooler period of the 100,000-year-cycle, yet instead of cooling our planet is experiencing extreme temperature rise leading to glaciers and ice sheets to melt.

The government has been reviewing its laws, policies, and regulations to identify any changes needed to support resilient use, facilities, and development that can withstand rising sea levels and protect global natural resources.

We don’t know yet if other government agencies will adopt a forward-thinking approach or if they will continue to focus on the way things used to be instead of dealing with the changes caused by climate change. But people around the world will have to learn permanently temporary living with rising seas.