Sea level rise

Definition

Sea level rise refers to the increase in the average level of the world's oceans due to the melting of ice sheets and glaciers, as well as the thermal expansion of seawater as it warms. This phenomenon is a significant indicator of climate change and is influenced by various factors, including greenhouse gas emissions and radiative forcing, which cause changes in temperature and water dynamics on Earth.

5 Must Know Facts For Your Next Test

1. Global sea levels have risen about 8 to 9 inches since 1880, with the rate accelerating in recent decades due to climate change.
2. The Intergovernmental Panel on Climate Change (IPCC) projects that sea levels could rise by 1 to 4 feet by 2100 if current trends continue, threatening coastal communities worldwide.
3. Sea level rise is not uniform globally; regions may experience higher or lower increases due to local factors like ocean currents and land subsidence.
4. In addition to direct impacts on coastal infrastructure, rising seas can lead to saltwater intrusion into freshwater aquifers, threatening drinking water supplies and agriculture.
5. Adaptation strategies for sea level rise include building seawalls, restoring wetlands, and implementing managed retreat in vulnerable areas.

Review Questions

• How does thermal expansion contribute to sea level rise, and what is its significance in the context of climate change?
  • Thermal expansion occurs when seawater warms and expands, leading to an increase in ocean volume and contributing significantly to sea level rise. As global temperatures continue to rise due to climate change, this effect becomes more pronounced, exacerbating the impacts of other factors like ice sheet melting. Understanding thermal expansion is crucial because it helps predict future sea level scenarios and informs coastal management strategies.
• Evaluate the implications of sea level rise for coastal communities and ecosystems.
  • Sea level rise poses serious threats to coastal communities through increased flooding, loss of habitat, and damage to infrastructure. Coastal ecosystems such as mangroves and wetlands are also at risk, which can lead to loss of biodiversity and decreased resilience against storms. The need for effective adaptation measures becomes essential as these communities face challenges that impact their economic stability and environmental health.
• Synthesize the relationship between greenhouse gas emissions, radiative forcing, and sea level rise.
  • Greenhouse gas emissions lead to radiative forcing by trapping heat in the Earth's atmosphere, which increases global temperatures. This warming contributes to both thermal expansion of seawater and accelerated melting of glaciers and ice sheets, directly causing sea level rise. By synthesizing these connections, it becomes clear that mitigating greenhouse gas emissions is essential for slowing down both climate change impacts and subsequent sea level rise, making it a critical focus for policy-making.

Related terms

Greenhouse Gases: Gases in Earth's atmosphere that trap heat, contributing to the greenhouse effect and influencing global temperatures, which play a crucial role in sea level rise.

Thermal Expansion: The increase in water volume that occurs when water is heated, contributing to rising sea levels as ocean temperatures increase.

Ice Sheet Melting: The process by which large masses of ice, such as Greenland and Antarctic ice sheets, melt due to rising temperatures, adding freshwater to the oceans and raising sea levels.