The Satellite Imagery Source

Search Image Hunter Now
Posted on November 5th, 2019

Our Changing Landscape – Okjökull Glacier

In this monthly feature, we span the globe to examine Our Changing Landscape with a time series of medium resolution RapidEye satellite imagery. The RapidEye archive dates back to late 2008 and already contains more than 14 billion square kilometers of data. From the changing of the seasons in Serengeti National Park, we travel north for this Our Changing Landscape to the first glacier-casualty of the Climate Change battle, Okjökull in Iceland.

Click on the image above to see an animation of 5-meter natural color RapidEye imagery collected over the Okjökull Glacier in Iceland on July 7, 2011, April 21, 2012, August 21, 2014 and August 19, 2019. We picked these four images to spread them across the RapidEye archive as evenly as possible. And yes we do recognize the April 2012 image is from a different season than the other summer images – and sure the July 2011 image was collected a full month before the August 2019 image. But even with these inconsistencies, we think this paints a very stark picture. One thing to take note of is the visible depth of the glacier at its center even in the July 2011 image, you can literally see the edges of Okjökull meaning it is quite tall at this time. However, in the August 2014 and 2019 images, the glacier is quite clearly nearly flat to the ground – further, there is much less surrounding snow in the August 2019 image than in the 2014 image. Goodbye poor Okjökull, you will be missed! (Images Courtesy: © Planet 2019)

The RapidEye Constellation

RapidEye is a constellation of five 5-meter (m) medium resolution satellites each offering five spectral bands of information. The RapidEye constellation offers daily revisits to every location on the planet with a huge footprint that is 77-km wide. The data is priced competitively with a starting cost of $1.28 per square kilometer for all five spectral bands – academics do receive discounts. RapidEye adds a fifth band, the red edge, to the ‘traditional’ multispectral set of blue, green, red and near-infrared (NIR). The additional spectral data in the red edge band allows users to extract more useful land ‘information’ than can be from traditional 4-band imagery sources. When RapidEye imagery is ordered as a Level 3A Orthorectified product, images from multiple dates are extremely well registered, making it the ideal data source for Our Changing Landscape.

The Melting of Okjökull Glacier, Iceland

According to Tulane University Professor Stephen Nelson, “a glacier is a permanent (on a human time scale, because nothing on the Earth is really permanent) body of ice, consisting largely of recrystallized snow, that shows evidence of downslope or outward movement due to the pull of gravity.” Located approximately 70 kilometers (44 miles) north-east of Reykjavik, Okjökull glacier stretched over 15 square kilometers (5.8 square miles) on top of Ok Mountain just 100 years ago. Today, the ice mass is less than 15 meters (49 feet) deep and only covers 1 square kilometer (0.62 square miles), leading glaciologists to declare it the first glacier lost to Climate Change. In fact, at an August 18th funeral, Okjökull was declared dead and a plaque commemorating the tragic event was installed.

It is no secret to regular readers of The Geospatial Times that Climate Change is a topic we tend to focus on, with clear recommendations that something needs to be done to address the global problem – for example our monthly look at the NOAA Climate Report in the Apollo News Snippet series. In fact, we have covered the rapid melting of global glaciers in this series, including Carroll Glacier and Glacier National Park. But before we turn to the 5-meter RapidEye archive over Okjökull, here is a quick reminder of just how dire the problem is with global ice mass coverage:

If you would like to find out more about using RapidEye for your academic studies, engineering projects or any landscape analysis, let us know at or (303) 993-3863.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

    The Geospatial Times Archive