Watching Antarctic Ice Sheets Crack with Landsat Imagery

We recently came across this interesting story about an ice shelf in Antarctica which is slowly breaking off. The original story is on the NASA website here. The article features a couple of Landsat images captured in December 2013, and December 2015. However, Landsat imagery is freely available and relatively easy to obtain and put into Google Earth.

Our current favourite method for browsing Landsat imagery is with NASA’s Earth Explorer as it allows you to quickly browse through the imagery available and download low resolution versions, which can easily be put into Google Earth Pro.

In this particular case there is a surprising amount of imagery of the location in question. As we saw when we looked at the coverage that Landsat provides, the imagery is divided into rows and columns that cluster together towards the poles. This means that polar locations actually get covered by several adjacent columns and get imaged every couple of days or so. Most parts of the world only get imaged once every 16 days. However, the poles are also dark for about half the year so there will only be good images during the summer months.

In addition, many of the images have significant cloud cover, so we had to go through them and choose ones that showed a clear view of the location we were interested in. As you can see below we were able to obtain imagery all the way from January 2000 to March 2016. The latest image in the series was captured just last Saturday! (March 12th). There seems to be a bit of a gap in imagery around 2004/2005 but we did not investigate why.


Animation showing the ice crack moving and growing over the years. Larger version

You can see the ice flow like a very slow river. It moves approximately 3.8 km in the 16 year period shown above.

If you wish to explore the imagery in Google Earth you can download this KML file. We have had to crop the Landsat images considerably, showing only the location of interest in order to make the file a reasonable size.

The crack from the story has a precursor in 2000, which was as far back as we could go. However, it only lengthens and widens in 2013, when it starts to look like part of the ice shelf is breaking off.

The default imagery for the location in Google Earth is Landsat imagery from about January 2003.

About Timothy Whitehead

Timothy has been using Google Earth since 2004 when it was still called Keyhole before it was renamed Google Earth in 2005 and has been a huge fan ever since. He is a programmer working for Red Wing Aerobatx and lives in Cape Town, South Africa.






PLEASE NOTE: Google Earth Blog is no longer writing regular posts. As a result, we are not accepting new comments or questions about Google Earth. If you have a question, use the official Google Earth and Maps Forums or the Google Earth Community Forums.



PLEASE NOTE: Google Earth Blog is no longer writing regular posts. As a result, we are not accepting new comments or questions about Google Earth. If you have a question, use the official Google Earth and Maps Forums or the Google Earth Community Forums.