As humans put more heat-trapping gases into the atmosphere, like carbon dioxide, ice around the planet melts. This melting can be a problem, particularly if the melting ice starts its life on land.
That’s because the melt water flows into the oceans, contributing to rising sea levels. Right now there are three main reasons that sea levels are rising. First, as ocean waters heat, they expand. Second, melting of ice in Antarctica flows into the ocean. Third, melting of ice on Greenland flows into the ocean. There is other melting, like mountain glaciers, but they are minor factors.
Read more on The Guardian.