1. Why are sea levels rising?
Global sea level rise occurs because of two factors. The biggest reason is because of something called "thermal expansion," which is simply that water expands as it warms, just like how the liquid in a thermometer expands as the temperature increases. Therefore, as global temperatures continue to rise, the oceans get warmer and they literally expand, making the level of the sea rise. The other main contributor to sea level rise is the loss of glaciers and the polar ice caps. When the glaciers and ice caps melt, that water flows into the ocean and increases its volume.