This upper layer is available in standard camouflage colours, such as yellow (for deserts) and green (for jungles).

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This relatively minor shift, the model found, still produces enough energy to initiate a wave-like pulse of crystal-shattering snow separation that quickly propagates uphill and leads to a major release of the upper layer.

MSN: How a deadly avalanche can be triggered

While the ozone layer in the upper atmosphere plays an important role in limiting harmful ultraviolet light reaching the Earth's surface, low-level ozone is a pollutant that is harmful, causing respiratory problems in animals as well as well-documented cases in humans.

BBC: Invasive plant 'increases ozone pollution'