1. Thermal Expansion: As the ocean absorbs vast amounts of heat from the atmosphere due to increased greenhouse gas concentrations, it undergoes thermal expansion. This process causes the volume of water to increase, resulting in higher sea levels. The ocean has a significant heat capacity, meaning it can store immense amounts of heat without experiencing major temperature changes. As a result, the effects of thermal expansion on sea levels will persist for many years, possibly decades or even centuries, even after emissions reductions.
2. Melting Ice: The increased atmospheric temperatures caused by global warming also lead to the melting of glaciers and ice sheets, particularly in Greenland and Antarctica. These vast ice reservoirs hold massive amounts of water, and as they continue to melt due to ongoing elevated temperatures, the additional freshwater released into the oceans also contributes to sea level rise. The melting of ice caps and glaciers is expected to persist for several decades due to the immense volume of ice involved and the time it takes for melting processes to slow down or halt.
Therefore, despite reaching net zero carbon emissions, sea levels will continue to rise due to thermal expansion and melting ice, and it may take many decades before the rate of sea level rise stabilizes. In order to address the urgency of the climate crisis, it is crucial to not only mitigate carbon emissions but also adapt to the current and future impacts of climate change, including rising sea levels, increasingly extreme weather events, and ecosystem changes.
