So far I’ve talked about Antarctica, but what about Greenland, the other ice sheet on Earth? Well, let’s begin an exploration of it! Greenland and Antarctica are the only two ice sheets on Earth. In simple terms, this means they are the two places where a very large amount of ice has been sitting on land for a very long time. (There is also a lot of sea ice in the Arctic, but remember that sea ice floats on water). Together, Antarctica and Greenland contain ~99% of all the freshwater on earth. If all the ice in the Greenland ice sheet melted, global sea level would rise about 6 m (20 ft). If all of the Antarctic Ice sheet melted, sea level would rise about 60 m (200 ft.)
Note: Sea ice is excluded from the images above. Only land ice (i.e. ice sheets) are shown.
What do you notice in the maps above? You can see Greenland is significantly smaller than Antarctica. Remember, Antarctica is roughly the size of the US? Well Greenland is about 3 times the size of Texas. Also notice Antarctica is close to centered over the South pole. On the other hand, Greenland is more offset from the North Pole. Another spatial difference is that in the Antarctic, there is land surrounded by water, whereas in the Arctic, there is water surrounded by land. This geographic difference in the arrangement of land vs. water gives rise to many differences in the climates of the two regions as well as other things.
In general, the Arctic is warmer, with temperatures typically between -43 and 5 degrees C (-45 and 41 degrees F), with temperatures up to 10 degrees C (50 degrees F) along the coast in the summer. The Antarctic is much colder, holding the world record of -89.2 degrees C (-128.6 degrees F) for the coldest temperature recorded on Earth in 1983! More typically, temperatures reach about -80 degrees C (-112 degrees F) in the interior in the winter, to between 5 degrees C (41 degrees F) and 15 degrees C (59 degrees F) along the coast in the summer.
While these temperatures might seem extremely cold, that’s what’s normal. However, especially in the Arctic, new record high temperatures are being recorded. And this warming trend is greater than the normal variability.
To put this in perspective, here’s a video showing surface temperature changing over the last 150 years. Notice the increasingly warm temperatures recorded in the Arctic over time.