I am pleased to announce that another extension of my Musaicum satellite image mosaic coverage is available now.

The Musaicum images are a series of regional satellite image mosaics based on Sentinel-2 data started in 2023 that are produced to a high quality standard. They offer unsurpassed quality in visual color depiction of Earth at this resolution range (10m) with a high degree of color consistency and an exceptionally low incidence of clouds.

The new regional mosaic covers the European Arctic Islands. That means Svalbard, Franz Josef Land and Novaya Zemlya. In terms of surface area covered this is the smallest of the Musaicum images published so far – but also one of the most interesting ones.

Svalbard, for example, is one of the most colorful regions on Earth, thanks to a highly diverse geology. These islands also take me back to the earliest local satellite image mosaics i introduced on this blog:

• New Franz Josef Land map
• Novaya Zemlya map
• Svalbard mosaic

A lot of progress has been made during the past ten years in terms of available data – we have several orders of magnitude more data available now – and in much better quality. While back in 2013 it was barely possible to assemble a full cloud free coverage of Franz Josef Land roughly at snow minimum – and this required going back to data from the 1980s, the new mosaic is almost fully based on data from just three years.

Accurate atmosphere compensation is still a big problem at high polar latitudes and astonishingly little progress has happened on that front during the past decade in techniques readily available – despite the raw image quality having improved so much. High polar latitudes are scarce in suitable reference surfaces to calibrate atmosphere compensation and, in addition, surface colors are highly variable over time. Further difficulty comes from the low sun position that you have during the late summer snow minimum. A substantial part of the development work that went into the newest version of the Musaicum process is related to dealing with these difficulties.

There is still room for improvement, but i can say without hesitation that this is most certainly the most consistent depiction of surface color of this region you have seen so far.

One thing you might notice is the mismatch in ocean color between the Musaicum image and the Green Marble ocean background you can observe at many of the non-glaciated coasts (like here). The reason for this is that the Green Marble ocean color is based on an average of all seasons with open, ice free water while the Musaicum data base is exclusively from late summer near the snow minimum. During snow melt, when the ocean is ice free already, the ocean color is often significantly brighter because of particles carried by the meltwater into the sea – causing the observed mismatch.

You can take a look at the product page of the new mosaic for more information and samples.

If – as i suspect it to be the case for most readers – the European Arctic Islands are not a region of high practical interest for you: There is of course also going to be additional Musaicum image coverage in other, more populated parts of the world. Where this is going to be also depends on you. Production planning is based on customer needs. So if you have an area where you need high quality imagery for and no Musaicum coverage is available yet i encourage you to get in touch.