What does rising sea levels refer to?

• A. Increased height of the level of seas and oceans
• B. Decreased height of the level of seas and oceans
• C. Increased salinity of the oceans
• D. More frequent tsunamis

Answer: (A)

Rising sea levels refer to the increased height of the surface of the seas and oceans. This means the average level of the ocean surface is higher than it used to be. The rise happens mainly because water expands as it warms (thermal expansion) and because meltwater from ice sheets and glaciers on land flows into the oceans. This isn’t about salinity changes or the occurrence of tsunamis—salinity is about salt content, and tsunamis are sudden, short-term waves usually caused by tectonic events, not a long-term rise in sea level. Understanding this helps explain why coastlines flood more easily and why storm surges can push farther inland even if the storm itself isn’t bigger.