Compare Images of Antarctic Sea Ice Extent Side-by-side
The pictures below show sea ice around the South Pole. Click on the popup menus above the pictures to choose which pictures to look at. You can look at two pictures at once and compare them.
- compare the sea ice in February and September for the same year (like February 2000 and September 2000)
- compare the sea ice in February for two different years (like February 1979 and February 2010)
- compare the sea ice in September for two different years
- click here if you want to look at sea ice in the northern hemisphere
Sea ice builds up during the winter when it is cold. When is there the most sea ice? There is usually a lot of sea ice in early spring, right after winter ends, around September. Remember, in the southern hemisphere, summer and winter happen at the opposite times of year from the northern hemisphere!
Over the summer, when it is warm, the sea ice melts. When is there the least sea ice? Since a lot of ice melts in the summer, there is usually much less sea ice in early fall around February, right after the end of summer.
The pink line in the pictures shows where the edge of the sea ice is, on average, in that month. Compare the edge of the ice in 1979 to the pink line. Now compare the edge of the ice in 2010 to the pink line. Do you see any difference?
Click here to see a movie of changes in sea ice over seven years (2002 to 2008). Watch how the ice melts in the summer and freezes and grows in the winter.
If you want to see more pictures of sea ice, go to the NSIDC web site to:
Shop Windows to the Universe Science Store!
The Fall 2009 issue of The Earth Scientist
, which includes articles on student research into building design for earthquakes and a classroom lab on the composition of the Earth’s ancient atmosphere, is available in our online store
You might also be interested in:
Sea ice is frozen seawater. It can be several meters thick and it moves over time. Although the salts in the seawater do not freeze, pockets of concentrated salty water become trapped in the sea ice when...more
What Will You Find There? South of the Antarctic Circle (at 66.5°S latitude) you will find the continent of Antarctica surrounded by the Southern Ocean, the geographic South Pole and the magnetic South...more
NASA recently started making images of the entire surface of the Earth every month. There are no clouds in the images. They combine many pictures taken at different times when the weather is clear in different...more
Let's get rid of some common misconceptions about the seasons. The Earth's orbit is in the shape of an ellipse, so that sometimes the Earth is a little bit closer to the Sun than at other times. Is this...more
There are two oceans in Earth's polar regions. The Arctic Ocean is in the north polar region. The Southern Ocean is in the south polar region. The oceans that are in the polar regions are a bit different...more
The Southern Ocean is a bit different. Many mapmakers do not even recognize it as an ocean. The Southern Ocean (sometimes known as the Antarctic Ocean or South Polar Ocean) surrounds Antarctica in the...more
Windows to the Universe and other educational programs of the University Corporation for Atmospheric Research Office of Education and Outreach invite you to explore Earth's polar regions with your students...more