Sea level rise

Sea level rise refers to the increase in the average height of the world's oceans, a phenomenon that has been observed over the past century and is projected to continue due to various factors, primarily global warming. The increase in sea levels is a significant concern due to its potential impacts on coastal communities, ecosystems, and the global climate system.

Causes

The primary causes of sea level rise can be divided into two categories: thermal expansion and the melting of ice.

Thermal Expansion

As the temperature of the ocean increases, the water expands. This thermal expansion accounts for about half of the observed sea level rise. The warming of the ocean is a direct result of global warming, which is caused by increased concentrations of greenhouse gases in the Earth's atmosphere, primarily from human activities such as the burning of fossil fuels and deforestation.

Melting of Ice

The other significant contributor to sea level rise is the melting of ice from glaciers, ice caps, and polar ice sheets. This melting adds large quantities of freshwater to the world's oceans. The most notable sources of ice melt include the Greenland Ice Sheet, the Antarctic Ice Sheet, and various glaciers around the world.

Impacts

Sea level rise poses numerous threats to human societies and natural ecosystems:

Coastal Erosion and Flooding

As sea levels rise, coastal areas become more susceptible to erosion and flooding, especially during storms and high tides. This can lead to the loss of property, infrastructure, and habitats for wildlife.

Saltwater Intrusion

The encroachment of saltwater into freshwater systems can degrade water quality and affect agricultural practices, water supply, and natural ecosystems.

Loss of Habitat

Many species depend on coastal habitats, which are being lost or altered due to rising sea levels. This includes mangroves, salt marshes, and coral reefs, which are critical for biodiversity and serve as natural barriers against coastal erosion and storms.

Mitigation and Adaptation

Efforts to address sea level rise fall into two categories: mitigation and adaptation.

Mitigation

Mitigation efforts aim to reduce the rate of sea level rise by addressing its root causes. This includes reducing greenhouse gas emissions through the transition to renewable energy sources, improving energy efficiency, and implementing policies aimed at carbon sequestration.

Adaptation

Adaptation strategies are designed to minimize the impacts of sea level rise. These can include the construction of sea walls and other coastal defenses, the restoration of natural barriers such as mangroves and reefs, and the development of policies to discourage construction in vulnerable areas.

Future Projections

Future projections of sea level rise vary depending on the emission scenario and the response of ice sheets to warming. According to the Intergovernmental Panel on Climate Change (IPCC), sea levels could rise by up to 1 meter (3 feet) by 2100 under high emission scenarios. However, recent studies suggest that the potential contribution from the Antarctic Ice Sheet could lead to even higher levels if global warming is not limited. Template:Climate change-stub