Sea level rise is the increase in the ocean's surface height relative to the land in a particular location. It is primarily caused by two factors linked to global warming: the melting of glaciers and ice sheets, which adds water to the ocean, and the thermal expansion of seawater as it warms. Warmer water expands and takes up more space, which contributes significantly to rising sea levels. This rise is driven by human-caused climate change, particularly the emission of greenhouse gases that have increased Earth's temperature. The warming has caused polar ice sheets, such as those in Greenland and Antarctica, and glaciers to melt at accelerated rates. Additionally, as the ocean absorbs the heat trapped by greenhouse gases, seawater expands, adding further to sea level rise. Sea level rise impacts coastal communities by increasing flood risks, threatening ecosystems and infrastructure. It is a major global concern due to its potential to displace populations and cause economic and environmental damage. Sea level rise has been accelerating in recent decades and continues to do so, with projections indicating more severe impacts if global warming exceeds 1.5–2 °C.