I am happy to introduce the fourth large regional high resolution mosaic from my Musaicum satellite image mosaic series.

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.

After the initial Europe mosaic and subsequent images of West Asia and the United States as well as various smaller images of islands this is the fourth big image. And it is a special one in a number of ways.

First, the region offers specific technical challenges that were not present in the previously covered regions. No part of East Asia poses a significant difficulty in image assembly due to clouds in absolute terms. For most of the area it is outright easy to find cloud free images. But in many parts these images are going to be outside the plant growth season and far away from the vegetation maximum and snow minimum, which i aim to depict. The vegetation maximum during the northern hemisphere summer in large parts features very high cloud incidence due to the influence of the summer Monsoon. For the same reason in many mountain areas in China there are two snow minima (one during summer and a second one after the end of Monsoon season).

As a result of this the volume of useful Sentinel-2 imagery available in the most difficult areas in the Eastern Himalaya is too small to allow for precise depiction of vegetation maximum and snow minimum. Even in the Green Marble (which uses many hundred source images) this is challenging.

So there is necessarily some use of off-season images (either too early and therefore with seasonal snow or too late and therefore with too little vegetation). But the extent of this non-ideal choice of source data is vastly less than in competing imagery products from other suppliers. Bottom line: This new mosaic is most certainly the most consistent depiction of that area you have seen and gives you a uniquely accurate impression of the distribution of vegetation and permanent snow and ice.

Another regional challenge is that agriculture in the region has a strong focus on rice growth. And rice plantations change their color quite rapidly during the growth season. This makes assembling a consistent image of agricultural areas difficult.

The second aspect that makes this mosaic special is the high diversity of the region in terms of land forms, climate and vegetation, but also in terms of human geography. The region features the highest mountains on Earth, extensive high altitude mountain regions and steep gorges but also deserts and steppes, a huge variety of forests, both on the mainland and on the islands and agriculture across many climate zones.

The contrasts in human geography are best illustrated by the inner Korean border, which is well visible on the Musaicum East Asia.

And finally the third aspect that made this mosaic special for me is that i learned a lot about the geography of the region, in particular of China, in the process. Chinese geography is historically very much neglected in Western education. The most significant white spots in Western knowledge of the planet in the early 20th century outside of the polar regions were in China. And huge parts of our knowledge and traditional geography education in the West about China still date back to the spotty insights obtained by European exploration of the region in the 19th and early 20th century. Having a reliable, consistent and representative color image of the whole country helps immensely to better understand it.

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