Types of ice

Not all ice that can be found in the Arctic is the same. There is drift ice and pack ice. Drift ice can be found in open seas. The ice got lose from glaciers or ice floes. It floats with the ocean current towards the equator which is why it is called drift ice.
For ship traffic the drift ice displays a great danger because especially from April to August in the busy north Atlantic there is a lot of drift ice in form of ice bergs. Pack ice is the most apparent sea ice type of all. When the ocean is covered with 80-100% with ice, we are talking about pack ice but there could be small, free water areas in between the ice. Then the ice is so dense that it displays an obstacle for ships and long walks on the ice are possible. Pack ice can be up to 3.5 m thick and depending on the season it covers 3-15 million km² of the Arctic Ocean. The Arctic ice swims in the water, in contrast to the Greenland ice which lies on land. When the Arctic ice melts the sea level doesn’t rise. It is like a glass of juice with ice cubes inside. When the ice inside the glass melts the juice doesn’t spill over the glass. If the Greenland ice would melt however, the melt water would spill into the ocean and the sea level would rise. About the impact and the Greenland ice in specific, you will learn more next week.